Subject: Review of RT MIB

From: Michael Boe <[email-masked]>
Date: Sun, 3 May 1998 17:33:31 -0700 (PDT)

Bob & Ken,

Well, these things happen..  You shout last call and people get serious about
reviewing a document :-). Good thing you were aggressive about bringing it to
last call, huh?

These comments are about the latest RT MIB version, and are from Derek Bolton.

/msb

ps:  Derek is correct about the FIC issue: RFC1647 only allows the server to
request definite-response on FIC only....and refers to the chain. I'm under the
impression that the client cannot respond to this until after receiving the
entire chain (ie, until the client receives the <EOR>).

------- Begin Forwarded Message -------
Comments tagged @DB:
-----------------------------------------------------

TN3270E Working Group                                      Kenneth White
INTERNET DRAFT: <draft-ietf-tn3270e-rt-mib-04.txt>             IBM Corp.
Expiration Date: October, 1998                              Robert Moore
                                                               IBM Corp.
April 1998

            Definitions of Protocol and Managed Objects for
              TN3270E Response Time Collection Using SMIv2
                            (TN3270E-RT-MIB)
                   <draft-ietf-tn3270e-rt-mib-04.txt>

Status of this Memo

This document is an Internet Draft.  Internet Drafts are working
documents of the Internet Engineering Task Force (IETF), its Areas, and
its Working Groups.  Note that other groups may also distribute working
documents as Internet Drafts.

Internet Drafts are draft documents valid for a maximum of six months.
Internet Drafts may be updated, replaced, or obsoleted by other
documents at any time.  It is not appropriate to use Internet Drafts as
reference material or to cite them other than as a "working draft" or
"work in progress."

Please check the I-D abstract listing contained in each Internet Draft
directory to learn the current status of this or any Internet Draft.
Distribution of this document is unlimited.

Copyright Notice

Copyright (C) The Internet Society (1998).  All Rights Reserved.

Abstract

This memo defines the protocol and the Management Information Base (MIB)
for performing response time data collection on TN3270 and TN3270E
sessions by a TN3270E server.  The response time data collected by a
TN3270E server is structured to support both validation of service level
agreements and performance monitoring of TN3270 and TN3270E Sessions.
This MIB has as a prerequisite the TN3270E-MIB, reference [16].

TN3270E, defined by RFC 1647 [15], refers to the enhancements made to
the Telnet 3270 (TN3270) terminal emulation practices.  Refer to RFC
1041 [14], RFC 854 [12], and RFC 860 [13] for a sample of what is meant
by TN3270 practices.

The specification of this MIB uses the Structure of Management
Information (SMI) for Version 2 of the Simple Network Management
Protocol (refer to RFC1902 [3]).

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Table of Contents

1.0  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .   2

2.0  The SNMP Network Management Framework   . . . . . . . . . . . .   3

3.0  Response Time Collection Methodology  . . . . . . . . . . . . .   3
3.1  General Response Time Collection  . . . . . . . . . . . . . . .   3
3.2  TN3270E Server Response Time Collection   . . . . . . . . . . .   5
3.3  Correlating TN3270E Server and Host Response Times  . . . . . .   9
3.4  Timestamp Calculation   . . . . . . . . . . . . . . . . . . . .  10
  3.4.1  DR Usage  . . . . . . . . . . . . . . . . . . . . . . . . .  10
  3.4.2  TIMEMARK Usage  . . . . . . . . . . . . . . . . . . . . . .  12
3.5  Performance Data Modelling  . . . . . . . . . . . . . . . . . .  13
  3.5.1  Averaging Response Times  . . . . . . . . . . . . . . . . .  13
  3.5.2  Response Time Buckets   . . . . . . . . . . . . . . . . . .  16

4.0  Structure of the MIB  . . . . . . . . . . . . . . . . . . . . .  17
4.1  tn3270eRtCollCtlTable   . . . . . . . . . . . . . . . . . . . .  17
4.2  tn3270eRtDataTable  . . . . . . . . . . . . . . . . . . . . . .  20
4.3  Notifications   . . . . . . . . . . . . . . . . . . . . . . . .  21
4.4  Advisory Spin Lock Usage  . . . . . . . . . . . . . . . . . . .  22

5.0  Definitions   . . . . . . . . . . . . . . . . . . . . . . . . .  22

6.0  Security Considerations   . . . . . . . . . . . . . . . . . . .  38

7.0  Intellectual Property   . . . . . . . . . . . . . . . . . . . .  39

8.0  Acknowledgments   . . . . . . . . . . . . . . . . . . . . . . .  39

9.0  References  . . . . . . . . . . . . . . . . . . . . . . . . . .  39

10.0  Authors' Addresses   . . . . . . . . . . . . . . . . . . . . .  41

11.0  Full Copyright Statement   . . . . . . . . . . . . . . . . . .  41

1.0  Introduction

This document is a product of the TN3270E Working Group.  It defines a
protocol and a MIB module to enable a TN3270E server to collect and keep
track of response time data for both TN3270 and TN3270E clients.  Basis
for implementing this MIB:

o   TN3270E-MIB, Base Definitions of Managed Objects for TN3270E Using
    SMIv2 [16].

o   TN3270E RFCs

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119, reference [19].

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2.0  The SNMP Network Management Framework

The SNMP Network Management Framework presently consists of six major
components.  They are:

o   the overall architecture, described in RFC 2271 [7].

o   the SMI, described in RFC 1902 [3], - the mechanisms used for
    describing and naming objects for the purpose of management.

o   the MIB-II, STD 17, RFC 1213 [2], - the core set of managed objects
    for the Internet suite of protocols.

o   the protocol, RFC 1157 [1] and/or RFC 1905 [6] and/or RFC 2272 [8]
    -- the protocol for accessing managed information.

o   the user-based security model defined in RFC 2274 [10].

o   the view-based access control model defined in RFC 2275 [11].

Textual conventions are defined in RFC 1903 [4], and conformance
statements are defined in RFC 1904 [5].  Common applications are defined
in RFC 2273 [9].

The Framework permits new objects to be defined for the purpose of
experimentation and evaluation.

This memo specifies a MIB module that is compliant to the SMIv2.  A MIB
conforming to the SMIv1 can be produced through the appropriate
translation.

3.0  Response Time Collection Methodology

This section explains the methodology and approach used by the MIB
defined by this memo for response time data collection by a TN3270E
server.

3.1  General Response Time Collection

Two primary methods exist for measuring response times in SNA networks:

o   The Systems Network Architecture Management Services (SNA/MS)
    Response Time Monitoring (RTM) function.

o   Timestamping using definite response flows.

This memo defines an approach using definite responses to timestamp the
flows between a client and its TN3270E server, rather than by use of the
RTM method. Extensions to the SNA/MS RTM flow were considered, but this
approach was deemed unsuitable since not all TN3270E server
implementations have access to their underlying SNA stacks.  The RTM
concepts of keeping response time buckets for service level agreements
and of interval-based response time collection for performance
monitoring are preserved in the MIB module defined in this memo.

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As mentioned, this memo focuses on using definite responses to timestamp
the flows between a client and its TN3270E server for generating
performance data.  Use of a definite response flow requires that the
client supports TN3270E with the RESPONSES function negotiated.  The
TN3270 TIMEMARK option can be used instead of definite response for
supporting TN3270 clients or TN3270E clients that don't support
RESPONSES.  This document focuses first on defining the protocol and
methods for generating performance data using definite responses, and
then describes how the TIMEMARK option can be used instead of definite
response.

In an SNA network, a transaction between a client Logical Unit (LU) and
a target host in general looks as follows:

        ------------------------------------------------
        |                                              |
        | Client LU                    Target SNA Host |
        |                                              |
        |                               Timestamps     |
        |              request              A          |
        | ----------------------------------------->   |
        |              reply(DR)            B      |   |
        | <---------------------------------------<    |
        | |            +/-RSP               C          |
        | >--------------------------------------->    |
        |                                              |
        | DR:     Definite Response requested          |
        | +/-RSP: Definite Response                    |
        |                                              |
        ------------------------------------------------

This transaction is a simple one, and is being used only to illustrate
how timestamping at a target SNA host can be used to generate response
times.  An IBM redbook [12] provides a more detailed description of
response time collection for a transaction of this type.  Note that for
the purpose of calculating an approximation for network transit time, it
doesn't matter if the response is positive or negative.  Two response
time values are typically calculated:

o   Host Transit Time:    Timestamp B - Timestamp A
o   Network Transit Time: Timestamp C - Timestamp B

Network transit time is an approximation for the amount of time that a
transaction requires to flow across a network, since the response flow
is being substituted for the request flow at the start of the
transaction.  Network transit time, timestamp C - timestamp B, is the
amount of time that the definite response request and its response
required.  Host time, timestamp B - timestamp A, is the actual time that
the host required to process the transaction.  Experience has shown that
using the response flow to approximate network transit times is useful,
and does correlate well with actual network transit times.

A client SHOULD respond to a definite response request when it completes
processing the transaction.  This is important since it increases the

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accuracy of a total response time.  Clients that immediately respond to
a definite response request will be attributed with lower total response
times then those that actually occurred.

The TN3270E-RT-MIB describes a method of collecting performance data
that is not appropriate for printer (LU Type 1 or LU Type 3) sessions;
thus collection of performance data for printer sessions is excluded
from this MIB.  This exclusion of printer sessions is not considered a
problem, since these sessions are not the most important ones for
response time monitoring, and since historically they were excluded from
SNA/MS RTM collection.  The tn3270eTcpConnResourceType object in a
tn3270eTcpConnEntry (in the TN3270E-MIB) can be examined to determine if
a client session is ineligible for response time data collection for
this reason.

3.2  TN3270E Server Response Time Collection

A TN3270E server connects a Telnet client performing 3270 emulation to a
target SNA host over both a client-side network (client to TN3270E
server) and an SNA Network (TN3270E server to target SNA host).  The
client-side network is typicaly TCP/IP, but it need not be.  For ease of
exposition this document uses the term "IP network" to refer to the
client-side network, since IP is by far the most common protocol for
these networks.

A TN3270E server can use SNA definite responses and the TN3270
Enhancement (RFC 1647 [15]) RESPONSES function to calculate response
times for a transaction, by timestamping when a client request arrives
at the server, when the reply arrives from the target host, and when the
response acknowledging this reply arrives from the client.

Section 3.4, Timestamp Calculation, provides specifics on when in the
sequence of flows between a TN3270E client and its target SNA host a
TN3270E server takes the required timestamps.  In addition, it provides
information on how a TN3270 TIMEMARK request/response flow can be used
instead of DR for approximating IP network transit times.

The following figure adds a TN3270E server between the client, in this
case a TN3270E client and the target SNA host:

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        ------------------------------------------------
        |                                              |
        | Client            TN3270E           Target   |
        |                    Server          SNA Host  |
        |                   Timestamps                 |
        |                                              |
        | <---IP Network-------><---SNA Network--->    |
        |                                              |
        |      request         D                       |
        | ------------------------------------------>  |
        |      reply(DR)       E                    |  |
        | <----------------------------------------<   |
        | |    +/-RSP          F                       |
        |  >-------------------- - - - - - - - - - >   |
        |                                              |
        ------------------------------------------------

A TN3270E server can save timestamp D when it receives a client request,
save timestamp E when the target SNA host replies, and save timestamp F
when the client responds to the definite response request that flowed
with the reply.  It doesn't matter whether the target SNA host requested
a definite response on its reply:  if it didn't, the TN3270E server
makes the request on its own, to enable it to produce timestamp F.  In
this case the TN3270E server does not forward the response to the target
SNA host, as the dotted line in the figure indicates.

In order to generate timestamp F, a TN3270E server MUST insure that the
transaction specifies DR, and that the TN3270E RESPONSES function has
been negotiated between itself and the client.  Negotiation of the
TN3270E RESPONSES function occurs during the client's TN3270E session
initialization.  The TN3270E servers that the authors are aware of do
request the RESPONSES function during client session initialization.
TN3270E clients either automatically support the RESPONSES function, or
can be configured during startup to support it.

Using timestamps D, E, and F the following response times can be
calculated by a TN3270E server:

o   Total Response time:     Timestamp F - Timestamp D
o   IP Network Transit Time: Timestamp F - Timestamp E

Just as in the SNA case presented above, these response times are also
approximations, since the final +/- RSP from the client is being
substituted for the request from the client that began the transaction.

The MIB provides an object, tn3270eRtCollCtlType, to control several
aspects of response time data collection.  One of the available options
in setting up a response time collection policy is to eliminate the
IP-network component altogether.  This might be done because it is
determined either that the additional IP network traffic would not be
desirable, or that the IP-network component of the overall response
times is not significant.

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Excluding the IP-network component from response times also has an
implication for the way in which response time data is aggregated.  A
TN3270E server may find that some of its clients simply don't support
any of the functions necessary for the server to calculate the
IP-network component of response times.  For these clients, the most
that the server can calculate is the SNA-network component of their
overall response times; the server records this SNA-network component as
the TOTAL response time each of these clients' transactions.  If a
response time collection is aggregating data from a number of clients,
some of which have the support necessary for including the IP-network
component in their total response time calculations, and some of which
do not, then the server aggregates the data differently depending on
whether the collection has been defined to include or exclude the
IP-network component:

o   If the IP-network component is included, then transactions for the
    clients that don't support calculation of the IP-network component
    of their response times are excluded from the aggregation
    altogether.

o   If the IP-network component is excluded, then total response times
    for ALL clients include only the SNA-network component, even though
    the server could have included an IP-network component in the
    overall response times for some of these clients.  The server does
    this by setting timestamp F, which marks the end of a transaction's
    total response time, equal to timestamp E, the end of the
    transaction's SNA-network component.

The principle here is that all the transactions contributing their
response times to an aggregated value MUST make the same contribution.
If the aggregation specifies that an IP-network component MUST be
included in the aggregation's response times, then transactions for
which an IP-network component cannot be calculated aren't included at
all.  If the aggregation specifies that an IP-network component is not
to be included, then only the SNA-network component is used, even for
those transactions for which an IP-network component could have been
calculated.

There is one more complication here:  the MIB allows a management
application to enable or disable dynamic definite responses for a
response time collection.  Once again the purpose of this option is to
give the network operator control over the amount of traffic introduced
into the IP network for response time data collection.  A DYNAMIC
definite response is one that the TN3270E server itself adds to a reply,
in a transaction for which the SNA application at the target SNA host
did not specify DR in its reply.  When the +/-RSP comes back from the
client, the server uses this response to calculate timestamp F, but then
it does not forward the response on to the SNA application (since the
application is not expecting a response to its reply).

The dynamic definite responses option is related to the option of
including or excluding the IP-network component of response times
(discussed above) as follows:

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o   If the IP-network component is excluded, then there is no reason for
    enabling dynamic definite responses:  the server always sets
    timestamp F equal to timestamp E, so the additional IP-network
    traffic elicited by a dynamic definite response would serve no
    purpose.

o   If the IP-network component is included, then enabling dynamic
    definite responses causes MORE transactions to be included in the
    aggregated response time values:

    -   For clients that do not support sending of responses, timestamp
        F can never be calculated, and so their transactions are never
        included in the aggregate.

    -   For clients that support sending of responses, timestamp F will
        always be calculated for transactions in which the host SNA
        application specifies DR in its reply, and so these transactions
        will always be included in the aggregate.

    -   For clients that support sending of responses, having dynamic
        definite responses enabled for a collection results in the
        inclusion of additional transactions in the aggregate:
        specifically, those for which the host SNA application did not
        specify DR in its reply.

A TN3270E server also has the option of substituting TIMEMARK processing
for definite responses in calculating the IP-network component of a
transaction's response time.  Once again, there is no reason for the
server to do this if the collection has been set up to exclude the
IP-network component altogether in computing response times.

The MIB is structured to keep counts and averages for total response
times (F - D) and their IP-network components (F - E).  A management
application can obviously calculate from these two values an average
SNA-network component (E - D) for the response times.  This SNA-network
component includes the SNA node processing time at both the TN3270E
server and at the target application.

A host TN3270E server refers to an implementation where the TN3270E
server is collocated with the Systems Network Architecture (SNA) System
Services Control Point (SSCP) for the dependent Secondary Logical Units
(SLUs) that the server makes available to its clients for connecting
into an SNA network.  A gateway TN3270E server resides on an SNA node
other than an SSCP, either an SNA type 2.0 node or an APPN node acting
in the role of a Dependent LU Requester (DLUR).

@DB: Just say " .. resides on a SNA PU Type 2 node."
It is wrong to restrict to 2.0, and the presence of a DLUR in
the path is irrelevant.

Host and gateway
TN3270E server implementations typically differ greatly as to their
internal implementation and System Definition (SYSDEF) requirements.

If a host TN3270E server is in the same SNA host as the target
application, then the SNA-network component of a transaction's response
time will approximately equal the host transit time (B - A) described
previously.  A host TN3270E server implementation can, however,
typically support the establishment of sessions to target applications
in SNA hosts remote from itself.  In this case the SNA-network component

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of the response time equals the actual SNA-network transit time plus two
host transit times.

@DB: There's another complication.  A special case arises when
the Host reply is "unbind".  Servers need to treat this as a
reply for Host response calculation purposes, or not count it
as a transaction?  How should it be handled wrt F-D?

3.3  Correlating TN3270E Server and Host Response Times

It is possible that response time data is collected from TN3270E servers
at the same time as a management application is monitoring the SNA
sessions at a host.  For example, a management application can be
monitoring a secondary logical unit (SLU) while retrieving data from a
TN3270E server.  Consider the following figure:

        ------------------------------------------------
        |                                              |
        | Client            TN3270E            Target  |
        |                    Server           SNA Host |
        |                   Timestamps         (PLU)   |
        |                    (SLU)           Timestamps|
        | <---IP Network-------><---SNA Network--->    |
        |                                              |
        |      request         D                 A     |
        | ------------------------------------------>  |
        |      reply(DR)       E                 B  |  |
        | <----------------------------------------<   |
        | |    +/-RSP          F                 C     |
        |  >-------------------------------------->    |
        |                                              |
        ------------------------------------------------

The following response times are available:

o   Target SNA host transit time:         Timestamp B - Timestamp A
o   Target SNA host network transit time: Timestamp C - Timestamp B
o   TN3270E server total response time:   Timestamp F - Timestamp D
o   TN3270E server IP-network component:  Timestamp F - Timestamp E

The value added by the TN3270E server in this situation is its
approximation of the IP-network component of the overall response time.

@DB: Not necessarily.  A-D and/or E-B may be significant.
Unfortunately, there's no way to apportion (E-D)-(B-A) between these.

The IP-network component can be subtracted from the total network
transit time (which can be captured at an SSCP monitoring SNA traffic
from/to the SLU) to see the actual SNA versus IP network transit times.

The MIB defined by this memo does not specifically address correlation
of the data it contains with response time data collected by direct
monitoring of SNA resources:  its focus is exclusively response time
data collection from a TN3270E server perspective.  It has, however, in
conjunction with the TN3270E-MIB [10], been structured to provide the
information necessary for correlation between TN3270E server-provided
response time information and that gathered from directly monitoring SNA
resources.

A management application attempting to correlate SNA resource usage to
Telnet clients can monitor either the tn3270eResMapTable or the
tn3270eTcpConnTable to determine resource-to-client address mappings.
Both of these tables are defined by the TN3270E-MIB [10].  Another

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helpful table is the tn3270eSnaMapTable, which provides a mapping
between SLU names as they are known at the SSCP (VTAM) and their local
names at the TN3270E server.  Neither the tn3270eClientGroupTable, the
tn3270eResPoolTable, nor the tn3270eClientResMapTable from the
TN3270E-MIB can be used for correlation, since the mappings defined by
these tables can overlap, and may not provide one-to-one mappings.

3.4  Timestamp Calculation

This section goes into more detail concerning when the various
timestamps can be taken as the flows between a TN3270E client and its
target SNA host pass through a TN3270E server.  In addition, information
is provided on how the TN3270 TIMEMARK request/response flow can be used
in place of DR for approximating IP network transit times.

3.4.1  DR Usage

Consider the following flow:

     ----------------------------------------------------------
     |                                                        |
     | Client            TN3270E            Target SNA        |
     |                    Server              Host            |
     |                   Timestamps                           |
     |                                                        |
     | <---IP Network-------><---SNA Network--->              |
     |                                                        |
     |      request         D    (BB,CD,OIC,ER)               |
     | ------------------------------------------->           |
     |      reply                (FIC,ER,EB)      |           |
     | <-----------------------------------------<            |
     |      reply                (MIC,ER)                     |
     | <-----------------------------------------<            |
     |      reply                (MIC,ER)                     |
     | <-----------------------------------------<            |
     |      reply(DR)       E    (LIC,DR)                     |
     | <-----------------------------------------<            |
     | |    +/-RSP          F                                 |
     |  >---------------------------------------->            |
     |                                                        |
     | BB : Begin Bracket    ER : Response by exception       |
     | EB : End Bracket      DR : Definite Response Requested |
     | CD : Change Direction FIC : First in chain             |
     | OIC: Only in chain    MIC: Middle in chain             |
     | LIC: Last in chain                                     |
     ----------------------------------------------------------

Timestamp D is taken at the TN3270E server when a client has sent data
to the server for forwarding to its target SNA host. This is most likely
when the server finds the end of record indicator in the TCP data
received from the client.

@DB: So if the server is unable to forward the data because of
lack of direction or SNA pacing, the delay gets included in
A-D, right?  The pacing bit's OK, but I'm not sure about
direction.  Seems to me that a client sending in before it
is really entitled to should not result in increased "host rsp
time".  Besides, it gets quite messy with, effectively, two
transactions being timed at once.  So I would define instant
D as "data from client and SNA direction is inbound or BETB".

The target SNA application returns its reply
in one or more SNA Request Units (RUs); in this example there are four
RUs in the reply.  The first RU is marked as first in chain (FIC), the
next two are marked as middle in chain (MIC), and the last is marked as
last in chain (LIC).  Timestamp E SHOULD be taken prior to sending the

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RESPONSES request to the client; normally this is done when the server
receives the LIC RU.

@DB: This is wrong.  The server has only one opportunity to send
"RESPONSE REQD" to the client, and that's on the FIC RU.
I think the intention is that timestamp E is when the last
segment of the LIC RU is received from the Host.

Timestamp F is taken when the RESPONSES response
is received from the client.

A target SNA application doesn't necessarily return data to a client in
a transaction; it may, for example, require more data from the client
before it can formulate a reply.  In this case the application may
simply return to the TN3270E server a change of direction indicator.  A
TCP connection is full duplex:  data can be received and sent on it at
the same time.  An SNA session, on the other hand, is half duplex, with
a change of direction indicator to alter the direction of data flow.
Timestamps E and F require a reply to flow to the client.  A best-effort
approach should be followed by a TN3270E server when it attempts to
calculate timestamps.  For cases where the target SNA application sends
a change of direction indicator rather than a reply, it is suggested
that the entire transaction be omitted from any response time
calculations.

@DB: I don't think that makes sense.  On sending in the request,
the client locks the keyboard.  If the appl sends null RU CD,
the server must invent a Write with a WCC that restores the
keyboard.  It might as well send this with RESPONSE REQD.
So the server can treat it as two separate transactions.

Another consideration is a mismatch between DR requested on the SNA side
and DR requested by a TN3270E server.  If the SNA host sends a
multiple-RU chain, the server does not know until the last RU is
received whether DR is being requested.  Meanwhile, the server may have
forwarded the first RU in the chain to the client.  In practice,
therefore, some servers convert ER flows to DR flows.  Timestamp E can
be taken when the first RESPONSES request flows to the client, and
timestamp F when its response is received.  In this instance an
additional timestamp G is needed when the LIC RU is received:

     ---------------------------------------------------
     |                                                 |
     | Client            TN3270E             Target    |
     |                    Server            SNA Host   |
     |                   Timestamps                    |
     |                                                 |
     | <---IP Network-------><---SNA Network--->       |
     |                                                 |
     |      request         D    (BB,CD,OIC,ER)        |
     | ------------------------------------------>     |
     |      reply(DR)       E    (FIC,ER,EB)     |     |
     | <----------------------------------------<      |
     | |     +/-RSP         F                          |
     |  >------------------->                          |
     |      reply                (MIC,ER)              |
     | <----------------------------------------<      |
     |      reply                (MIC,ER)              |
     | <----------------------------------------<      |
     |      reply(DR)            (LIC,DR)              |
     | <----------------------------------------<      |
     | |    +/-RSP          G                          |
     |  >------------------->                          |
     |                                                 |
     ---------------------------------------------------

@DB: I don't think the client is supposed to respond
until it has received EOR.  Michael?
That (DR) on the LIC to the client is only
possible if the server creates an extra Write after
sending all the data from the Host.  It cannot insert (DR)
between the TN3270E header and EOR.

The response times can then be calculated as follows:

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o   Total response time:     Timestamp G - Timestamp D
o   IP network transit time: Timestamp F - Timestamp E

If DR is requested by the LIC RU, then the TN3270E server can may either
its response or the earlier one for approximating IP network transit
time.

@DB: "can may"?

3.4.2  TIMEMARK Usage

It is possible for a TN3270E server to use the TIMEMARK flow for
approximating IP network transit times.  Using TIMEMARKs would make it
possible for a server to collect performance data for TN3270 clients, as
well as for TN3270E clients that do not support the RESPONSES function.
In order for TIMEMARKs to be used in this way, a client can't have the
NOP option enabled, since responses are needed to the server's TIMEMARK
requests.  An IP network transit time approximation using a TIMEMARK is
basically the amount of time it takes for a TN3270 server to receive
from a client a response to a TIMEMARK request.

To get an estimate for IP network transit time, a TN3270E server sends a
TIMEMARK request to a client after a LIC RU has been received, as a
means of approximating IP network transit time:

     ---------------------------------------------------
     |                                                 |
     | Client            TN3270E             Target    |
     |                    Server              Host     |
     |                   Timestamps                    |
     |                                                 |
     | <---IP Network-------><---SNA Network--->       |
     |                                                 |
     |      request         D    (BB,CD,OIC,ER)        |
     | ------------------------------------------->    |
     |      reply                (FIC,ER,EB)      |    |
     | <-----------------------------------------<     |
     |      reply                (MIC,ER)              |
     | <-----------------------------------------<     |
     |      reply                (MIC,ER)              |
     | <-----------------------------------------<     |
     |      reply           E    (LIC,ER)              |
     | <-----------------------------------------<     |
     |      TIMEMARK Rqst   E'                         |
     | <---------------------                          |
     | |    TIMEMARK Rsp    F'                         |
     |  >------------------->                          |
     |                                                 |
     ---------------------------------------------------

The response times can then be calculated as follows:

o   TN3270E server total response time:
            (Timestamp E - Timestamp D) + (Timestamp F' - Timestamp E')

o   TN3270E server IP network time:  Timestamp F' - Timestamp E'

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If a TN3270E server is performing the TIMEMARK function (independent of
the response time monitoring use of the function discussed here), then
it most likely has a TIMEMARK interval for determining when to examine
client sessions for sending the TIMEMARK request.  This interval, which
is ordinarily a global value for an entire TN3270E server, is
represented in the TN3270E-MIB by the tn3270eSrvrConfActivityInterval
object.  A TIMEMARK request is sent only if, when it is examined, a
client session is found to have had no activity for a different fixed
length of time, represented in the TN3270E-MIB by the
tn3270eSrvrConfActivityTimeout object.

Servers that support a large number of client sessions should spread out
the TIMEMARK requests they send to these clients over the activity
interval, rather than sending them all in a single burst, since
otherwise the network may be flooded with TIMEMARK requests.  When a
server uses TIMEMARKs for approximating response times, this tends to
introduce a natural spreading into its TIMEMARK requests, since the
requests are triggered by the arrival of traffic from an SNA host.

A TN3270E server MUST integrate its normal TIMEMARK processing with its
use of TIMEMARKs for computing response times.  In particular, it MUST
NOT send a second TIMEMARK request to a client while waiting for the
first to return, since this is ruled out by the TIMEMARK protocol
itself.  If a TIMEMARK flow has just been performed for a client shortly
before the LIC RU arrives, the server MAY use the interval from this
flow as its approximation for IP network transit time, (in other words,
as its (F' - E') value) when calculating its approximation for the
transaction's total response time, rather than sending a second TIMEMARK
request so soon after the preceding one.

Regardless of when the server sends its TIMEMARK request, the accuracy
of its total response time calculation depends on exactly when the
client responds to the TIMEMARK request.

3.5  Performance Data Modelling

The following two subsections detail how the TN3270E-RT-MIB models and
controls capture of two types of response time data:  average response
times and response time buckets.

3.5.1  Averaging Response Times

Average response times play two different roles in the MIB:

o   They are made available for management applications to retrieve.
o   They serve as triggers for emitting notifications.

Sliding-window averages are used rather than straight interval-based
averages, because they are often more meaningful, and because they cause
less notification thrashing.  Sliding-window average calculation can, if
necessary, be disabled, by setting the sample period multiplier,
tn3270eRtCollCtlSPMult, to 1, and setting the sample period,
tn3270eRtCollCtlSPeriod, to the required collection interval.

In order to calculate sliding-window averages, a TN3270E server MUST:

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o   Select a fixed, relatively short, sample period SPeriod; the default
    value for SPeriod in the MIB is 20 seconds.

o   Select an averaging period multiplier SPMult.  The actual collection
    interval will then be SPMult times SPeriod.  The default value for
    SPMult in the MIB is 30, yielding a default collection interval of
    10 minutes.  Note that the collection interval (SPMult*SPeriod) is
    always a multiple of the sample period.

@DB: A word of warning is appropriate here.  The way SPMult is used
in the sliding average calculation does not translate directly into
"the averaging period is SPMult*SPeriod."  In fact, if you look at
the way that the contribution of any particularly sample decays
with time, SPMult*SPeriod is its "half-life".  So it gives a
better feel for the behavior to say that the effective averaging
period is 2*SPMult*SPeriod.

o   Maintain the following counters to keep track of activity within the
    current sample period; these are internal counters, not made visible
    to a management application via the MIB.

    -   T (number of transactions in the period)

    -   TotalRts (sum of the total response times for all transactions
        in the period)

    -   TotalIpRts (sum of the IP network transit times for all
        transactions in the period; note that if IP network transit
        times are being excluded from the response time collection, this
        value will always be 0).

o   Also maintain sliding counters, initialized to zero, for each of the
    quantities being counted:

    -   AvgCountTrans (sliding count of transactions)
    -   TotalRtsSliding (sliding count of total response times)
    -   TotalIpRtsSliding (sliding count of IP network transit times)

o   At the end of each sample period, update the sliding interval
    counters, using the following floating-point calculations:

             AvgCountTrans = AvgCountTrans + T
                  - (AvgCountTrans / SPMult)

             TotalRtsSliding = TotalRtsSliding + TotalRts
                  - (TotalRtsSliding / SPMult)

             TotalIpRtsSliding = TotalIpRtsSliding + TotalIpRts
                  - (TotalIpRtsSliding / SPMult)

    Then reset T, TotalRts, and TotalIpRts to zero for use during the
    next sample period.

o   At the end of a collection interval, update the following MIB
    objects as indicated; the floating-point numbers are rounded rather
    than truncated.

        tn3270eRtDataAvgCountTrans = AvgCountTrans
        tn3270eRtDataAvgRt = TotalRtsSliding / AvgCountTrans
        tn3270eRtDataAvgIpRt = TotalIpRtsSliding / AvgCountTrans

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    As expected, if IP network transit times are being excluded from
    response time collection, then tn3270eRtDataAvgIpRt will always
    return 0.

The sliding transaction counter AvgCountTrans is not used for updating
the MIB object tn3270eRtDataCountTrans:  this object is an ordinary SMI
Counter32, which maintains a total count of transactions since its last
discontinuity event.  The sliding counters are used only for calculating
averages.

Two mechanisms are present in the MIB to inhibit the generation of an
excessive number of notifications related to average response times.
First, there are high and low thresholds for average response times. A
tn3270eRtExceeded notification is generated the first time a
statistically significant average response time is found to have
exceeded the high threshold.  (The test for statistical significance is
described below.)  After this, no other tn3270eRtExceeded notifications
are generated until an average response time is found to have fallen
below the low threshold.

The other mechanism to limit notifications is the significance test for
a high average response time.  Intuitively, the significance of an
average is directly related to the number of samples that go into it; so
we might be inclined to use a rule such as "for the purpose of
generating tn3270eRtExceeded notifications, ignore average response
times based on fewer than 20 transactions in the sample period."

In the case of response times, however, the number of transactions
sampled in a fixed sampling period is tied to these transactions'
response times.  A few transactions with long response times can
guarantee that there will not be many transactions in a sample, because
these transactions "use up" the sampling time.  Yet this case of a few
transactions with very poor response times should obviously be
classified as a problem, not as a statistical anomaly based on too small
a sample.

The solution is to make the significance level for a sample a function
of the average response time.  A value IdleCount is specified, which is
used to qualify an sample as statistically significant.  In order to
determine at a collection interval whether to generate a
tn3270eRtExceeded notification, a TN3270E server uses the following
algorithm:

   if AvgCountTrans * ((AvgRt/ThreshHigh - 1) ** 2) <  IdleCount
   then generate the notification,

@DB: ">=" ?

where AvgRt is the value that would be returned by the object
tn3270eRtDataAvgRt at the end of the interval, and the "**" notation
indicates exponientiation.

Two examples illustrate how this algorithm works.  Suppose that
IdleCount has been set to 20 transactions, and the high threshold to 200
msecs per transaction.  If the average observed response time is 300
msecs, then a notification will be generated only if AvgCountTrans >=

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80.  If, however, the observed response time is 500 msecs, then a
notification is generated if AvgCountTrans >= 9.

There is no corresponding significance test for the tn3270eRtOkay
notification:  this notification is generated based on an average
response time that falls below the low threshold, regardless of the
sample size behind that average.

3.5.2  Response Time Buckets

The MIB also supports collection of response time data into a set of
five buckets. This data is suitable either for verification of service
level agreements, or for monitoring by a management application to
identify performance problems.  The buckets provide counts of
transactions whose total response times fall into a set of specified
ranges.

Like everything for a collection, the "total" response times collected
in the buckets are governed by the specification of whether IP network
transit times are to be included in the totals.  Depending on how this
option is specified, the response times being counted in the buckets
will either be total response times (F - D), or only SNA network transit
times (effectively E - D, because when it is excluding the IP-network
component of transactions, a server makes timestamp F identical to
timestamp E).

Four bucket boundaries are specified for a response time collection,
resulting in five buckets.  The first response time bucket counts those
transactions whose total response times were less than or equal to
Boundary 1, the second bucket counts those whose response times were
greater than Boundary 1 but less than or equal to Boundary 2, and so on.
The fifth bucket is unbounded on the top, counting all transactions
whose response times were greater than Boundary 4.

The four bucket boundaries have default values of:  1 second, 2 seconds,
5 seconds, and 10 seconds, respectively.  These values are the defaults
in the 3174 controller's implementation of the SNA/MS RTM function, and
are thought to be appropriate for this MIB as well.

In SNA/MS the counter buckets were (by today's standards) relatively
small, with a maximum value of 65,535.  The bucket objects in the MIB
are all Counter32's.

The following figure represents the buckets pictorially:

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         ----------------------------------------------
         |                                            |
         |          Response Time Boundaries          |
         | |       |       |       |       |       |  |
         | |       |       |       |       |       |  |
         | |       |       |       |       |      no  |
         | 0      B-1     B-2     B-3     B-4    bound|
         | |       |       |       |       |       |  |
         | |Bucket1|Bucket2|Bucket3|Bucket4|Bucket5|  |
         | -----------------------------------------  |
         |                                            |
         ----------------------------------------------

4.0  Structure of the MIB

The TN3270E-RT-MIB has the following components:

o   tn3270eRtCollCtlTable
o   tn3270eRtDataTable
o   Notifications
o   Advisory Spin Lock Usage

4.1  tn3270eRtCollCtlTable

The tn3270eRtCollCtlTable is indexed by tn3270eSrvrConfIndex and
tn3270eClientGroupName imported from the TN3270E-MIB.
tn3270eSrvrConfIndex identifies within a host a particular TN3270E
server.  tn3270eClientGroupName identifies a collection of IP clients
for which response time data is to be collected.  The set of clients is
defined using the tn3270eClientGroupTable from the TN3270E-MIB.

A tn3270eRtCollCtlEntry contains the following objects:

             --------------------------------------------------
   1st Index | tn3270eSrvrConfIndex             Unsigned32    |
   2nd Index | tn3270eClientGroupName           Utf8String    |
             | tn3270eRtCollCtlType             BITS          |
             | tn3270eRtCollCtlSPeriod          Unsigned32    |
             | tn3270eRtCollCtlSPMult           Unsigned32    |
             | tn3270eRtCollCtlThreshHigh       Unsigned32    |
             | tn3270eRtCollCtlThreshLow        Unsigned32    |
             | tn3270eRtCollCtlIdleCount        Unsigned32    |
             | tn3270eRtCollCtlBucketBndry1     Unsigned32    |
             | tn3270eRtCollCtlBucketBndry2     Unsigned32    |
             | tn3270eRtCollCtlBucketBndry3     Unsigned32    |
             | tn3270eRtCollCtlBucketBndry4     Unsigned32    |
             | tn3270eRtCollCtlRowStatus        RowStatus     |
             --------------------------------------------------

The tn3270eRtCollCtlType object controls the type(s) of response time
collection that occur, the granularity of the collection, whether
dynamic definite responses SHOULD be initiated, and whether
notifications SHOULD be generated.  This object is of BITS SYNTAX, and
thus allows selection of multiple options.

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The BITS in the tn3270eRtCollCtlType object have the following meanings:

o   aggregate(0) - If this bit is set to 1, then data SHOULD be
    aggregated for the whole client group.  In this case there will be
    only one row created for the collection in the tn3270eRtDataTable.
    The first two indexes for this row, tn3270eSrvrConfIndex and
    tn3270eClientGroupName, will have the same values as the indexes as
    the corresponding tn3270eRtCollCtlEntry.  The third and fourth
    indexes of an aggregated tn3270eRtDataEntry have the values
    unknown(0) (tn3270eRtDataClientAddrType) and a zero-length octet
    string (tn3270eRtDataClientAddress).

    If this bit is set to 0, then a separate entry is created in the
    tn3270eRtDataTable for each member of the client group.  In this
    case the tn3270eRtDataClientAddress contains the client's actual IP
    Address, and tn3270eRtDataClientAddrType indicates the address type.

o   excludeIpComponent(1) - If this bit is set to 1, then the server
    SHOULD exclude the IP-network component from all the response times
    for this collection.  If the target SNA application specifies DR in
    any of its replies, this DR will still be passed down to the client,
    and the client's response will still be forwarded to the
    application.  But this response will play no role in the server's
    response time calculations.

    If this bit is set to 0, then the server includes in the collection
    only those transactions for which it can include an (approximate)
    IP-network component in the total response time for the transaction.
    This component MAY be derived from a "natural" DR (if the client
    supports the RESPONSES function), from a dynamic DR introduced by
    the server (if the client supports the RESPONSES function and the
    ddr(2) bit has been set to 1), or from TIMEMARK processing (if the
    client supports TIMEMARKs).

    If this bit is set to 1, then the ddr(2) bit is ignored, since there
    is no reason for the server to request additional responses from the
    client(s) in the group.

o   ddr(2) - If this bit is set to 1, then the server SHOULD, for those
    clients in the group that support the RESPONSES function, add a DR
    request to a reply in each transaction (usually, but not necessarily
    the LIC reply),

@DB: Can only be on the FIC or after the LIC.

    and use the client's subsequent response for
    calculating an (approximate) IP-network component to include in the
    transaction's total response times.

    If this bit is set to 0, then the server does not add a DR request
    to any replies from the target SNA application.

    If the excludeIpComponent(1) bit is set to 1, then this bit is
    ignored by the server.

o   average(3) - If this bit is set to 1, then the server SHOULD
    calculate a sliding-window average for the collection, based on the
    parameters specified for the group.

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    If this bit is set to 0, then an average is not calculated.  In this
    case the tn3270eRtExceeded and tn3270eRtOkay notifications are not
    generated, even if the traps(5) bit is set to 1.

o   buckets(4) - If this bit is set to 1, then the server SHOULD create
    and increment response time buckets for the collection, based on the
    parameters specified for the group.

    If this bit is set to 0, then response time buckets are not created.

o   traps(5) - If this bit is set to 1, then a TN3270E Server is enabled
    to generate notifications pertaining to an tn3270eCollCtlEntry.
    tn3270CollStart and tn3270CollEnd generation is enabled simply by
    traps(5) being set to 1.  tn3270eRtExceeded and tn3270eRtOkay
    generation enablement requires that average(3) be set to 1 in
    addition to the traps(5) requirement.

    If traps(5) is set to 0, then none of the notifications defined in
    this MIB are generated for a particular tn3270eRtCollCtlEntry.

Either the average(3) or the buckets(4) bit MUST be set to 1 in order
for response time data collection to occur; both bits MAY be set to 1.
If the average(3) bit is set to 1, then the following objects have
meaning, and are used to control the calculation of the averages, as
well as the generation of the two notifications related to them:

o   tn3270eRtCollCtlSPeriod
o   tn3270eRtCollCtlSPMult
o   tn3270eRtCollCtlThreshHigh
o   tn3270eRtCollCtlThreshLow
o   tn3270eRtCollCtlIdleCount

The previous objects' values are meaningless if the associated
average(3) bit is not set to 1.

If the buckets(4) bit is set to 1, then the following objects have
meaning, and specify the bucket boundaries:

o   tn3270eRtCollCtlBucketBndry1
o   tn3270eRtCollCtlBucketBndry2
o   tn3270eRtCollCtlBucketBndry3
o   tn3270eRtCollCtlBucketBndry4

The previous objects' values are meaningless if the associated
buckets(4) bit is not set to 1.

If an entry in the tn3270RtCollCtlTable has the value active(1) for its
RowStatus, then an implementation SHALL NOT allow Set operations for any
objects in the entry except:

o   tn3270eRtCollCtlThreshHigh
o   tn3270eRtCollCtlThreshLow
o   tn3270eRtCollCtlRowStatus

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4.2  tn3270eRtDataTable

Either a single entry or multiple entries are created in the
tn3270eRtDataTable for each tn3270eRtCollCtlEntry, depending on whether
tn3270eRtCollCtlType in the control entry has aggregate(0) selected.
The contents of an entry in the tn3270eRtDataTable depend on the
contents of the corresponding entry in the tn3270eRtCollCtlTable:  as
described above, some objects in the data entry return meaningful values
only when the average(3) option is selected in the control entry, while
others return meaningful values only when the buckets(4) option is
selected.  If both options are selected, then all the objects return
meaningful values.  When an object is not specified to return a
meaningful value, an implementation may return any syntactically valid
value in response to a Get operation.

The following objects return meaningful values if and only if the
average(3) option was selected in the corresponding
tn3270eRtCollCtlEntry:

o   tn3270eRtDataAvgRt
o   tn3270eRtDataAvgIpRt
o   tn3270eRtDataAvgCountTrans
o   tn3270eRtDataIntTimeStamp
o   tn3270eRtDataTotalRts
o   tn3270eRtDataTotalIpRts
o   tn3270eRtDataCountTrans
o   tn3270eRtDataCountDrs
o   tn3270eRtDataElapsRndTrpSq
o   tn3270eRtDataElapsIpRtSq

The first three objects in this list return values derived from the
sliding-window average calculations described earlier.  The time of the
most recent sample for these calculations is returned in the
tn3270eRtDataIntTimeStamp object.  The next four objects are normal
Counter32 objects, maintaining counts of total response time and total
transactions.  The last two objects return sum of the squares values, to
enable variance calculations by a management application.

The following objects return meaningful values if and only if the
buckets(4) option was selected in the corresponding
tn3270eRtCollCtlEntry:

o   tn3270eRtDataBucket1Rts
o   tn3270eRtDataBucket2Rts
o   tn3270eRtDataBucket3Rts
o   tn3270eRtDataBucket4Rts
o   tn3270eRtDataBucket5Rts

A discontinuity object, tn3270eRtDataDiscontinuityTime, can be used by a
management application to detect when the values of the counter objects
in this table may have been reset, or otherwise experienced a
discontinuity.  A possible cause for such a discontinuity is the TN3270E
server's being stopped or restarted.  This object returns a meaningful
value regardless of which collection control options were selected.

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An object, tn3270eRtDataRtMethod, identifies whether the IP Network Time
was calculated using either the definite response or TIMEMARK approach.

When an entry is created in the tn3270eRtCollCtlTable with its
tn3270eRtCollCtlType aggregate(0) bit set to 1, an entry is
automatically created in the tn3270eRtDataTable; this entry's
tn3270eRtDataClientAddress has the value of a zero-length octet string,
and its tn3270eRtDataClientAddrType has the value of unknown(0).

When an entry is created in the tn3270eRtCollCtlTable with its
tn3270eRtCollCtlType aggregate(0) bit set to 0, a separate entry is
created in the tn3270eRtDataTable for each member of the client group
that currently has a session with the TN3270E server.  Entries are
subsequently created for clients that the TN3270E server determines to
be members of the client group when these clients establish sessions
with the server.  Entries are also created when clients with existing
sessions are added to the group.

All entries associated with a tn3270eRtCollCtlEntry are deleted from the
tn3270eRtDataTable when that entry is deleted from the
tn3270eRtCollCtlTable.  An entry for an individual client in a client
group is deleted when its TCP connection terminates.  Once it has been
created, a client's entry in the tn3270eRtDataTable remains active as
long as the collection's tn3270eRtCollCtlEntry exists, even if the
client is removed from the client group for the tn3270eRtCollCtlEntry.

4.3  Notifications

This MIB defines four notifications related to a tn3270eRtDataEntry.  If
the associated tn3270eRtCollCtlType object's traps(5) bit is set to 1,
then the tn3270RtCollStart and tn3270RtCollEnd notifications are
generated when, respsectively, the tn3270eRtDataEntry is created and
deleted.  If, in addition, this tn3270eRtCollCtlType object's average(3)
bit is set to 1, then the the tn3270eRtExceeded and tn3270eRtOkay
notifications are generated when the conditions they report occur.

The following notifications are defined by this MIB:

o   tn3270eRtExceeded - The purpose of this notification is to signal
    that a performance problem has been detected.  If average(3)
    response time data is being collected, then this notification is
    generated whenever (1) an average response time is first found, on a
    collection interval boundary, to have exceeded the high threshold
    tn3270eRtCollCtlThreshHigh specified for the client group, AND (2)
    the sample on which the average is based is determined to have been
    a significant one, via the significance algorithm described earlier.
    This notification is not generated again for a tn3270eRtDataEntry
    until an average response time falling below the low threshold
    tn3270eRtCollCtlThreshLow specified for the client group has
    occurred for the entry.

o   tn3270eRtOkay - The purpose of this notification is to signal that a
    previously reported performance problem has been resolved. If
    average(3) response time data is being collected, then this
    notification is generated whenever (1) a tn3270eRtExceeded

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    notification has already been generated, AND (2) an average response
    time is first found, on a collection interval boundary, to have
    fallen below the low threshold tn3270eRtCollCtlThreshLow specified
    for the client group.  This notification is not generated again for
    a tn3270eRtDataEntry until an average response time exceeding the
    high threshold tn3270eRtCollCtlThreshHigh specified for the client
    group has occurred for the entry.

Taken together, the two preceding notifications serve to minimize the
generation of an excessive number of traps in the case of an average
response time that oscillates about its high threshold.

o   tn3270eRtCollStart - This notification is generated whenever data
    collection begins for a client group, or when a new
    tn3270eRtDataEntry becomes active.  The primary purpose of this
    notification is signal to a management application that a new client
    TCP session has been established, and to provide the IP-to-resource
    mapping for the session.  This notification is not critical when
    average(3) data collection is not being performed for the client
    group.

o   tn3270eRtCollEnd - This notification is generated whenever a data
    collection ends.  For an aggregate collection, this occurs when the
    corresponding tn3270eRtCollCtlEntry is deleted.  For an individual
    collection, this occurs either when the tn3270eRtCollCtlEntry is
    deleted, or when the client's TCP connection terminates.  The
    purpose of this notification is to enable a management application
    to complete a monitoring function that it was performing, by
    returning final values for the collection's data objects.

4.4  Advisory Spin Lock Usage

Within the TN3270E-RT-MIB, tn3270eRtSpinLock is defined as an advisory
lock that allows cooperating TN3270E-RT-MIB applications to coordinate
their use of the tn3270eRtCollCtlTable.  When creating a new entry or
altering an existing entry in the tn3270eRtCollCtlTable, an application
SHOULD make use of tn3270eRtSpinLock to serialize application changes or
additions.  Since this is an advisory lock, its use by management
applications SHALL NOT be not enforced by agents.  Agents MUST, however,
implement the tn3270eRtSpinLock object.

5.0  Definitions

  TN3270E-RT-MIB DEFINITIONS ::= BEGIN

  IMPORTS
      MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
      Counter32, Unsigned32, Gauge32
                  FROM SNMPv2-SMI
      RowStatus, DateAndTime, TimeStamp, TestAndIncr
                  FROM SNMPv2-TC
      MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
                  FROM SNMPv2-CONF
      Tn3270eAddrType, Tn3270eTAddress, tn3270eSrvrConfIndex,

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      tn3270eClientGroupName, tn3270eResMapElementType
                  FROM TN3270E-MIB
      snanauMIB
                  FROM SNA-NAU-MIB;

    tn3270eRtMIB   MODULE-IDENTITY
        LAST-UPDATED "9804300000Z" -- April 30, 1998
        ORGANIZATION "TN3270E Working Group"
        CONTACT-INFO
          "Kenneth White ([email-masked])
           IBM Corp. - Dept. BRQA/Bldg. 501/G114
           P.O. Box 12195
           3039 Cornwallis
           RTP, NC 27709-2195

           Robert Moore ([email-masked])
           IBM Corp. - Dept. BRQA/Bldg. 501/G114
           P.O. Box 12195
           3039 Cornwallis
           RTP, NC 27709-2195
           (919) 254-4436"
       DESCRIPTION
          "This module defines a portion of the management
          information base (MIB) that enables monitoring of
          TN3270 and TN3270E clients' response times by a
          TN3270E server."
  ::= { snanauMIB 9 }
  -- snanauMIB ::= { mib-2 34 }

  -- Top level structure of the MIB

  tn3270eRtNotifications   OBJECT IDENTIFIER  ::= { tn3270eRtMIB 0 }
  tn3270eRtObjects         OBJECT IDENTIFIER  ::= { tn3270eRtMIB 1 }
  tn3270eRtConformance     OBJECT IDENTIFIER  ::= { tn3270eRtMIB 3 }

  -- MIB Objects

  -- Response Time Control Table

  tn3270eRtCollCtlTable  OBJECT-TYPE
      SYNTAX       SEQUENCE OF Tn3270eRtCollCtlEntry
      MAX-ACCESS   not-accessible
      STATUS       current
      DESCRIPTION
        "The response time monitoring collection control table,
        which allows a management application to control the
        types of response time data being collected, and the
        clients for which it is being collected.

        This table is indexed by tn3270eSrvrConfIndex and
        tn3270eClientGroupName imported from the
        TN3270E-MIB.  tn3270eSrvrConfIndex indicates within
        a host which TN3270E server an entry applies to.
        tn3270eClientGroupName it identifies the set of IP
        clients for which response time data is being collected.

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        The particular IP clients making up the set are identified
        in the tn3270eClientGroupTable in the TN3270E-MIB."
      ::= { tn3270eRtObjects 1}

  tn3270eRtCollCtlEntry    OBJECT-TYPE
      SYNTAX        Tn3270eRtCollCtlEntry
      MAX-ACCESS    not-accessible
      STATUS        current
      DESCRIPTION
        "An entry in the TN3270E response time monitoring collection
        control table.  To handle the case of multiple TN3270E
        servers on the same host, the first index of this table is
        the tn3270eSrvrConfIndex from the TN3270E-MIB."
      INDEX {
        tn3270eSrvrConfIndex,    -- Server's index
        tn3270eClientGroupName } -- What to collect on
      ::= { tn3270eRtCollCtlTable 1 }

  Tn3270eRtCollCtlEntry ::= SEQUENCE {
      tn3270eRtCollCtlType              BITS,
      tn3270eRtCollCtlSPeriod           Unsigned32,
      tn3270eRtCollCtlSPMult            Unsigned32,
      tn3270eRtCollCtlThreshHigh        Unsigned32,
      tn3270eRtCollCtlThreshLow         Unsigned32,
      tn3270eRtCollCtlIdleRate          Unsigned32,
      tn3270eRtCollCtlBucketBndry1      Unsigned32,
      tn3270eRtCollCtlBucketBndry2      Unsigned32,
      tn3270eRtCollCtlBucketBndry3      Unsigned32,
      tn3270eRtCollCtlBucketBndry4      Unsigned32,
      tn3270eRtCollCtlRowStatus         RowStatus   }

  -- The OID { tn3270eRtCollCtlEntry 1 } is not used

  tn3270eRtCollCtlType  OBJECT-TYPE
      SYNTAX    BITS {
                       aggregate(0),
                       excludeIpComponent(1),
                       ddr(2),
                       average(3),
                       buckets(4),
                       traps(5)
                     }
      MAX-ACCESS   read-create
      STATUS       current
      DESCRIPTION
        "This object controls what types of response time data to
         collect, whether to summarize the data across the members
         of a client group or keep it individually, whether to
         introduce dynamic definite responses, and whether to
         generate traps.

         aggregate(0)          - Aggregate response time data for
                                 the client group as a whole.  If
                                 this bit is set to 0, then
                                 maintain response time data

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                                 separately for each member of the
                                 client group.
         excludeIpComponent(1) - Do not include the IP-network
                                 component in any response times.
         ddr(2)                - Enable dynamic definite response.
         average(3)            - Produce an average response time
                                 based on a specified collection
                                 interval.
         buckets(4)            - Maintain tn3270eRtDataBucket values
                                 in an corresponding
                                 tn3270eRtDataEntry, based on the
                                 bucket boundaries specified in the
                                 tn3270eRtDataBucketBndry objects.
         traps(5)              - generate the traps specified in
                                 this MIB module.  The
                                 tn3270eRtExceeded and
                                 tn3270eRtOkay are generated
                                 only if average(3) is also
                                 specified."
      ::= { tn3270eRtCollCtlEntry 2 }

  tn3270eRtCollCtlSPeriod OBJECT-TYPE
      SYNTAX  Unsigned32 (15..86400) -- 15 second min, 24 hour max
      UNITS   "seconds"
      MAX-ACCESS   read-create
      STATUS       current
      DESCRIPTION
        "The number of seconds that defines the sample period.
         The actual interval is defined as tn3270eRtCollCtlSPeriod
         times tn3270eRtCollCtlSPMult.

         The value of this object is used only if the corresponding
         tn3270eRtCollCtlType has the average(3) setting."
      DEFVAL   {20}    -- 20 seconds
      ::= { tn3270eRtCollCtlEntry 3 }

  tn3270eRtCollCtlSPMult OBJECT-TYPE
      SYNTAX  Unsigned32 (1..5760) -- 5760 x SPeriod of 15 is 24 hours
      UNITS   "period"
      MAX-ACCESS   read-create
      STATUS       current
      DESCRIPTION
        "The sample period multiplier; this value is multiplied by
        the sample period, tn3270eRtCollCtlSPeriod, to determine
        the collection interval.

        Sliding-window average calculation can, if necessary, be
        disabled, by setting the sample period multiplier,
        tn3270eRtCollCtlSPMult, to 1, and setting the sample
        period, tn3270eRtCollCtlSPeriod, to the required
        collection interval.

        The value of this object is used only if the corresponding
        tn3270eRtCollCtlType has the average(3) setting."
      DEFVAL   { 30 }    -- yields an interval of 10 minutes when

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                         -- used with the default SPeriod value
      ::= { tn3270eRtCollCtlEntry 4 }

  tn3270eRtCollCtlThreshHigh  OBJECT-TYPE
      SYNTAX            Unsigned32
      UNITS             "seconds"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The threshold for generating a tn3270eRtExceeded
        notification, signalling that a monitored total response
        time has exceeded the specified limit.  A value of zero
        for this object suppresses generation of this notification.
        The value of this object is used only if the corresponding
        tn3270eRtCollCtlType has average(3) and traps(5) selected."
      DEFVAL   { 0 }   -- suppress notifications
      ::= { tn3270eRtCollCtlEntry 5 }

  tn3270eRtCollCtlThreshLow   OBJECT-TYPE
      SYNTAX            Unsigned32
      UNITS             "seconds"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The threshold for generating a tn3270eRtOkay notification,
        signalling that a monitored total response time has fallen
        below the specified limit.  A value of zero for this object
        suppresses generation of this notification.  The value of
        this object is used only if the corresponding
        tn3270eRtCollCtlType has average(3) and traps(5) selected."
      DEFVAL   { 0 }   -- suppress notifications
      ::= { tn3270eRtCollCtlEntry 6 }

  tn3270eRtCollCtlIdleRate   OBJECT-TYPE
      SYNTAX            Unsigned32
      UNITS             "transactions"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The value of this object is used to determine whether a
        sample that yields an average response time exceeding the
        value of tn3270eRtCollCtlThreshHigh was a statistically
        valid one.  If the following statement is true, then the
        sample was statistically valid, and so a tn3270eRtExceeded
        notification should be generated:

          AvgCountTrans * ((AvgRt/ThreshHigh - 1) ** 2) <  IdleRate

        This comparison is done only if the corresponding
        tn3270eRtCollCtlType has average(3) and traps(5) selected."
      DEFVAL { 1 }
      ::= { tn3270eRtCollCtlEntry 7 }

  tn3270eRtCollCtlBucketBndry1   OBJECT-TYPE
      SYNTAX            Unsigned32

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      UNITS             "tenths of seconds"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The value of this object defines the range of transaction
         response times counted in the Tn3270eRtDataBucket1Rts
         object: those less than or equal to this value."
      DEFVAL { 10 }
      ::= { tn3270eRtCollCtlEntry 8 }

  tn3270eRtCollCtlBucketBndry2   OBJECT-TYPE
      SYNTAX            Unsigned32
      UNITS             "tenths of seconds"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The value of this object, together with that of the
        tn3270eRtCollCtlBucketBndry1 object, defines the range
        of transaction response times counted in the
        Tn3270eRtDataBucket2Rts object: those greater than the
        value of the tn3270eRtCollCtlBucketBndry1 object, and
        less than or equal to the value of this object."
      DEFVAL { 20 }
      ::= { tn3270eRtCollCtlEntry 9 }

  tn3270eRtCollCtlBucketBndry3   OBJECT-TYPE
      SYNTAX            Unsigned32
      UNITS             "tenths of seconds"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The value of this object, together with that of the
        tn3270eRtCollCtlBucketBndry2 object, defines the range of
        transaction response times counted in the
        Tn3270eRtDataBucket3Rts object:  those greater than the
        value of the tn3270eRtCollCtlBucketBndry2 object, and less
        than or equal to the value of this object."
      DEFVAL { 50 }
      ::= { tn3270eRtCollCtlEntry 10 }

  tn3270eRtCollCtlBucketBndry4   OBJECT-TYPE
      SYNTAX            Unsigned32
      UNITS             "tenths of seconds"
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "The value of this object, together with that of the
        tn3270eRtCollCtlBucketBndry3 object, defines the range
        of transaction response times counted in the
        Tn3270eRtDataBucket4Rts object: those greater than the
        value of the tn3270eRtCollCtlBucketBndry3 object, and
        less than or equal to the value of this object.

        The value of this object also defines the range of
        transaction response times counted in the

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        Tn3270eRtDataBucket5Rts object: those greater than the
        value of this object."
      DEFVAL { 100 }
      ::= { tn3270eRtCollCtlEntry 11 }

  tn3270eRtCollCtlRowStatus  OBJECT-TYPE
      SYNTAX            RowStatus
      MAX-ACCESS        read-create
      STATUS            current
      DESCRIPTION
        "This object allows entries to be created and deleted
         in the tn3270eRtCollCtlTable.  An entry in this table
         is deleted by setting this object to destroy(6).
         Deleting an entry in this table has the side-effect
         of removing all entries from the tn3270eRtDataTable
         that are associated with the entry being deleted."
      ::= { tn3270eRtCollCtlEntry 12 }

  -- TN3270E Response Time Data Table

  tn3270eRtDataTable  OBJECT-TYPE
      SYNTAX       SEQUENCE OF Tn3270eRtDataEntry
      MAX-ACCESS   not-accessible
      STATUS       current
      DESCRIPTION
        "The response time data table.  Entries in this table are
         created based on entries in the tn3270eRtCollCtlTable."
      ::= { tn3270eRtObjects 2 }

  tn3270eRtDataEntry  OBJECT-TYPE
      SYNTAX        Tn3270eRtDataEntry
      MAX-ACCESS    not-accessible
      STATUS        current
      DESCRIPTION
        "An entry in this table is created based upon the
         tn3270eRtCollCtlTable.  A single entry is created with
         a tn3270eRtDataClientAddrType of unknown(0) and a
         zero-length octet string value for
         tn3270eRtDataClientAddress when the corresponding
         tn3270eRtCollCtlType has aggregate(0) specified.
         When aggregate(0) is not specified, then a separate
         entry is created for each client in the group.

         Note that the following objects defined within an
         entry in this table can wrap:
            tn3270eRtDataTotalRts
            tn3270eRtDataTotalIpRts
            tn3270eRtDataCountTrans
            tn3270eRtDataCountDrs
            tn3270eRtDataElapsRnTrpSq
            tn3270eRtDataElapsIpRtSq
            tn3270eRtDataBucket1Rts
            tn3270eRtDataBucket2Rts
            tn3270eRtDataBucket3Rts

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            tn3270eRtDataBucket4Rts
            tn3270eRtDataBucket5Rts"
      INDEX {
         tn3270eSrvrConfIndex,      -- Server's local index
         tn3270eClientGroupName,    -- Collection target
         tn3270eRtDataClientAddrType,
         tn3270eRtDataClientAddress }
      ::= { tn3270eRtDataTable 1 }

  Tn3270eRtDataEntry ::= SEQUENCE {
         tn3270eRtDataClientAddrType        Tn3270eAddrType,
         tn3270eRtDataClientAddress         Tn3270eTAddress,
         tn3270eRtDataDiscontinuityTime     TimeStamp,
         tn3270eRtDataAvgRt                 Gauge32,
         tn3270eRtDataAvgIpRt               Gauge32,
         tn3270eRtDataAvgCountTrans         Gauge32,
         tn3270eRtDataIntTimeStamp          DateAndTime,
         tn3270eRtDataTotalRts              Counter32,
         tn3270eRtDataTotalIpRts            Counter32,
         tn3270eRtDataCountTrans            Counter32,
         tn3270eRtDataCountDrs              Counter32,
         tn3270eRtDataElapsRndTrpSq         Unsigned32,
         tn3270eRtDataElapsIpRtSq           Unsigned32,
         tn3270eRtDataBucket1Rts            Counter32,
         tn3270eRtDataBucket2Rts            Counter32,
         tn3270eRtDataBucket3Rts            Counter32,
         tn3270eRtDataBucket4Rts            Counter32,
         tn3270eRtDataBucket5Rts            Counter32,
         tn3270eRtDataRtMethod              INTEGER
     }

  tn3270eRtDataClientAddrType   OBJECT-TYPE
      SYNTAX    Tn3270eAddrType
      MAX-ACCESS   not-accessible
      STATUS       current
      DESCRIPTION
        "Indicates the type of address represented by
         the value of tn3270eRtDataClientAddress."
      ::= { tn3270eRtDataEntry 1 }

  tn3270eRtDataClientAddress   OBJECT-TYPE
      SYNTAX    Tn3270eTAddress
      MAX-ACCESS   not-accessible
      STATUS       current
      DESCRIPTION
        "Contains the IP address of the TN3270 client being
         monitored.  A zero-length octet string is used if
         aggregate data is being collected for the client group."
      ::= { tn3270eRtDataEntry 2 }

  tn3270eRtDataDiscontinuityTime OBJECT-TYPE
      SYNTAX      TimeStamp
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION

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          "The value of sysUpTime on the most recent occasion at
          which one or more of this entry's counter objects
          suffered a discontinuity.  This may happen if a TN3270E
          server is stopped and then restarted, and local methods
          are used to set up collection policy
          (tn3270eRtCollCtlTable entries)."
      ::= { tn3270eRtDataEntry 3 }

  tn3270eRtDataAvgRt OBJECT-TYPE
      SYNTAX       Gauge32
      UNITS        "tenths of seconds"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The average total response time measured over the last
        collection interval."
      DEFVAL { 0 }
      ::= { tn3270eRtDataEntry 4 }

  tn3270eRtDataAvgIpRt OBJECT-TYPE
      SYNTAX       Gauge32
      UNITS        "tenths of seconds"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The average IP response time measured over the last
        collection interval."
      DEFVAL { 0 }
      ::= { tn3270eRtDataEntry 5 }

  tn3270eRtDataAvgCountTrans   OBJECT-TYPE
      SYNTAX       Gauge32
      UNITS        "transactions"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The sliding transaction count used for calculating the
        values of the tn3270eRtDataAvgRt and tn3270eRtDataAvgIpRt
        objects.  The actual transaction count is available in
        the tn3270eRtDataCountTrans object.

@DB: Change "actual" to "cumulative".

        The initial value of this object, before any averages have
        been calculated, is 0."
      ::= { tn3270eRtDataEntry 6 }

  tn3270eRtDataIntTimeStamp   OBJECT-TYPE
      SYNTAX       DateAndTime
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The date and time of the last interval that
        tn3270eRtDataAvgRt, tn3270eRtDataAvgIpRt, and
        tn3270eRtDataAvgCountTrans were calculated.

        Prior to the calculation of the first interval

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        averages, this object returns the value
        0x0000000000000000000000.  When this value is
        returned, the remaining objects in the entry have
        no significance."
      ::= { tn3270eRtDataEntry 7 }

  tn3270eRtDataTotalRts   OBJECT-TYPE
      SYNTAX       Counter32
      UNITS        "tenths of seconds"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the total response times collected.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 8 }

  tn3270eRtDataTotalIpRts   OBJECT-TYPE
      SYNTAX       Counter32
      UNITS        "tenths of seconds"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the total IP-network response times
        collected.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 9 }

  tn3270eRtDataCountTrans   OBJECT-TYPE
      SYNTAX       Counter32
      UNITS        "transactions"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the total number of transactions detected.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 10 }

  tn3270eRtDataCountDrs   OBJECT-TYPE
      SYNTAX       Counter32
      UNITS        "definite responses"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the total number of definite responses
        detected.

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        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 11 }

  tn3270eRtDataElapsRndTrpSq   OBJECT-TYPE
      SYNTAX       Unsigned32
      UNITS        "tenths of seconds squared"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The sum of the elapsed round trip time squared.  The sum
        of the squares is keep in order to enable calculation of
        a variance."

@DB: "kept"

      DEFVAL { 0 }
      ::= { tn3270eRtDataEntry 12 }

  tn3270eRtDataElapsIpRtSq   OBJECT-TYPE
      SYNTAX       Unsigned32
      UNITS        "tenths of seconds squared"
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The sum of the elapsed IP round trip time squared.
        The sum of the squares is keep in order to enable
        calculation of a variance."
      DEFVAL { 0 }
      ::= { tn3270eRtDataEntry 13 }

  tn3270eRtDataBucket1Rts   OBJECT-TYPE
      SYNTAX       Counter32
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the response times falling into bucket 1.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 14 }

  tn3270eRtDataBucket2Rts   OBJECT-TYPE
      SYNTAX       Counter32
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the response times falling into bucket 2.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 15 }

  tn3270eRtDataBucket3Rts   OBJECT-TYPE
      SYNTAX       Counter32

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      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the response times falling into bucket 3.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 16 }

  tn3270eRtDataBucket4Rts  OBJECT-TYPE
      SYNTAX       Counter32
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the response times falling into bucket 4.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 17 }

  tn3270eRtDataBucket5Rts  OBJECT-TYPE
      SYNTAX       Counter32
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The count of the response times falling into bucket 5.

        A management application can detect discontinuities in this
        counter by monitoring the tn3270eRtDataDiscontinuityTime
        object."
      ::= { tn3270eRtDataEntry 18 }

  tn3270eRtDataRtMethod OBJECT-TYPE
      SYNTAX       INTEGER {
                             none(0),
                             responses(1),
                             timemark(2)
                           }
      MAX-ACCESS   read-only
      STATUS       current
      DESCRIPTION
        "The value of this object indicates the method that was
        used in calculating the IP network time.

        The value 'none(0) indicates that response times were not
        calculated for the IP network."
      ::= { tn3270eRtDataEntry 19 }

  tn3270eRtSpinLock OBJECT-TYPE
      SYNTAX      TestAndIncr
      MAX-ACCESS  read-write
      STATUS      current
      DESCRIPTION

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        "An advisory lock used to allow cooperating TN3270E-RT-MIB
        applications to coordinate their use of the
        tn3270eRtCollCtlTable.

        When creating a new entry or altering an existing entry
        in the tn3270eRtCollCtlTable, an application should make
        use of tn3270eRtSpinLock to serialize application changes
        or additions.

        Since this is an advisory lock, the use of this lock is
        not enforced."
      ::= { tn3270eRtObjects 3 }

  -- Notifications

  tn3270eRtExceeded   NOTIFICATION-TYPE
      OBJECTS {
         tn3270eRtDataIntTimeStamp,
         tn3270eRtDataAvgRt,
         tn3270eRtDataAvgIpRt,
         tn3270eRtDataAvgCountTrans,
         tn3270eRtDataRtMethod
      }
      STATUS  current
      DESCRIPTION
        "This notification is generated when the average response
        time, tn3270eRtDataAvgRt, exceeds
        tn3270eRtCollCtlThresholdHigh at the end of a collection
        interval specified by tn3270eCollCtlSPeriod
        times tn3270eCollCtlSPMult.  Note that the corresponding
        tn3270eCollCtlType must have traps(5) and average(3) set
        for this notification to be generated.  In addition,
        tn3270eRtDataAvgCountTrans, tn3270eRtCollCtlThreshHigh, and
        tn3270eRtDataAvgRt are algorithmically compared to
        tn3270eRtCollCtlIdleRate for determination if this
        notification will be suppressed."
      ::= { tn3270eRtNotifications 1 }

  tn3270eRtOkay   NOTIFICATION-TYPE
      OBJECTS {
         tn3270eRtDataIntTimeStamp,
         tn3270eRtDataAvgRt,
         tn3270eRtDataAvgIpRt,
         tn3270eRtDataAvgCountTrans,
         tn3270eRtDataRtMethod
      }
      STATUS  current
      DESCRIPTION
        "This notification is generated when the average response
        time, tn3270eRtDataAvgRt, falls below
        tn3270eRtCollCtlThresholdLow at the end of a collection
        interval specified by tn3270eCollCtlSPeriod times
        tn3270eCollCtlSPMult, after a tn3270eRtExceeded
        notification was generated.  Note that the corresponding
        tn3270eCollCtlType must have traps(5) and average(3)

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        set for this notification to be generated."
      ::= { tn3270eRtNotifications 2 }

  tn3270eRtCollStart NOTIFICATION-TYPE
      OBJECTS {
         tn3270eRtDataRtMethod,       -- type of collection
         tn3270eResMapElementType     -- type of resource
      }
      STATUS  current
      DESCRIPTION
        "This notification is generated when response time data
        collection is enabled for a member of a client group.
        In order for this notification to occur the corresponding
        tn3270eRtCollCtlType must have traps(5) selected.

        tn3270eResMapElementType contains a valid value only if
        tn3270eRtDataClientAddress contains a valid address
        (rather than a zero-length octet string)."
      ::= { tn3270eRtNotifications 3 }

  tn3270eRtCollEnd   NOTIFICATION-TYPE
      OBJECTS {
         tn3270eRtDataDiscontinuityTime,
         tn3270eRtDataAvgRt,
         tn3270eRtDataAvgIpRt,
         tn3270eRtDataAvgCountTrans,
         tn3270eRtDataIntTimeStamp,
         tn3270eRtDataTotalRts,
         tn3270eRtDataTotalIpRts,
         tn3270eRtDataCountTrans,
         tn3270eRtDataCountDrs,
         tn3270eRtDataElapsRndTrpSq,
         tn3270eRtDataElapsIpRtSq,
         tn3270eRtDataBucket1Rts,
         tn3270eRtDataBucket2Rts,
         tn3270eRtDataBucket3Rts,
         tn3270eRtDataBucket4Rts,
         tn3270eRtDataBucket5Rts,
         tn3270eRtDataRtMethod
      }
      STATUS  current
      DESCRIPTION
        "This notification is generated when an tn3270eRtDataEntry
        is deleted after being active (actual data collected), in
        order to enable a management application monitoring an
        tn3270eRtDataEntry to get the entry's final values.  Note
        that the corresponding tn3270eCollCtlType must have traps(5)
        set for this notification to be generated."
      ::= { tn3270eRtNotifications 4 }

  -- Conformance Statement

  tn3270eRtGroups       OBJECT IDENTIFIER ::= { tn3270eRtConformance 1 }
  tn3270eRtCompliances  OBJECT IDENTIFIER ::= { tn3270eRtConformance 2 }

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  -- Compliance statements

  tn3270eRtCompliance     MODULE-COMPLIANCE
      STATUS current
      DESCRIPTION
        "The compliance statement for agents that support the
        TN327E-RT-MIB."
      MODULE   -- this module
         MANDATORY-GROUPS { tn3270eRtGroup, tn3270eRtNotGroup }

      OBJECT tn3270eRtCollCtlType
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation to
            this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlSPeriod
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to allow the user to change
            the default value of this object, and is allowed to
            use a different default."

      OBJECT tn3270eRtCollCtlSPMult
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlThreshHigh
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlThreshLow
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlIdleRate
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlBucketBndry1
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlBucketBndry2
         MIN-ACCESS  read-only

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         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlBucketBndry3
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlBucketBndry4
         MIN-ACCESS  read-only
         DESCRIPTION
            "The agent is not required to support a SET operation
            to this object in the absence of adequate security."

      OBJECT tn3270eRtCollCtlRowStatus
         SYNTAX   INTEGER {
                           active(1) -- subset of RowStatus
                          }
         MIN-ACCESS read-only
         DESCRIPTION
            "Write access is not required, and only one of the six
            enumerated values for the RowStatus textual convention
            need be supported, specifically: active(1)."

      ::= {tn3270eRtCompliances 1 }

  -- Group definitions

  tn3270eRtGroup         OBJECT-GROUP
      OBJECTS {
          tn3270eRtCollCtlType,
          tn3270eRtCollCtlSPeriod,
          tn3270eRtCollCtlSPMult,
          tn3270eRtCollCtlThreshHigh,
          tn3270eRtCollCtlThreshLow,
          tn3270eRtCollCtlIdleRate,
          tn3270eRtCollCtlBucketBndry1,
          tn3270eRtCollCtlBucketBndry2,
          tn3270eRtCollCtlBucketBndry3,
          tn3270eRtCollCtlBucketBndry4,
          tn3270eRtCollCtlRowStatus,
          tn3270eRtDataDiscontinuityTime,
          tn3270eRtDataAvgRt,
          tn3270eRtDataAvgIpRt,
          tn3270eRtDataAvgCountTrans,
          tn3270eRtDataIntTimeStamp,
          tn3270eRtDataTotalRts,
          tn3270eRtDataTotalIpRts,
          tn3270eRtDataCountTrans,
          tn3270eRtDataCountDrs,
          tn3270eRtDataElapsRndTrpSq,
          tn3270eRtDataElapsIpRtSq,
          tn3270eRtDataBucket1Rts,

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          tn3270eRtDataBucket2Rts,
          tn3270eRtDataBucket3Rts,
          tn3270eRtDataBucket4Rts,
          tn3270eRtDataBucket5Rts,
          tn3270eRtDataRtMethod,
          tn3270eRtSpinLock }
      STATUS  current
      DESCRIPTION
        "This group is mandatory for all implementations that
        support the TN3270E-RT-MIB. "
      ::= { tn3270eRtGroups 1 }

  tn3270eRtNotGroup         NOTIFICATION-GROUP
      NOTIFICATIONS {
          tn3270eRtExceeded,
          tn3270eRtOkay,
          tn3270eRtCollStart,
          tn3270eRtCollEnd
       }
      STATUS  current
      DESCRIPTION
        "The notifications that must be supported when the
        TN3270E-RT-MIB is implemented. "
      ::= { tn3270eRtGroups 2 }

  END

6.0  Security Considerations

Certain management information defined in this MIB may be considered
sensitive in some network environments.  Therefore, authentication of
received SNMP requests and controlled access to management information
SHOULD be employed in such environments.  An authentication protocol is
defined in [10].  A protocol for access control is defined in [11].

Several objects in this MIB allow write access or provide for row
creation.  Allowing this support in a non-secure environment can have a
negative effect on network operations.  It is RECOMMENDED that
implementers seriously consider whether set operations or row creation
SHOULD be allowed without providing, at a minimum, authentication of
request origin.  It is RECOMMENDED that without such support that the
following objects be implemented as read-only:

o   tn3270eRtCollCtlType
o   tn3270eRtCollCtlSPeriod
o   tn3270eRtCollCtlSPMult
o   tn3270eRtCollCtlThreshHigh
o   tn3270eRtCollCtlThreshLow
o   tn3270eRtCollCtlIdleCount
o   tn3270eRtCollCtlBucketBndry1
o   tn3270eRtCollCtlBucketBndry2
o   tn3270eRtCollCtlBucketBndry3
o   tn3270eRtCollCtlBucketBndry4
o   tn3270eRtCollCtlRowStatus

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The administrative method to use to create and manage the
tn3270eRtCollCtlTable when SET support is not allowed is outside of the
scope of this memo.

7.0  Intellectual Property

The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to pertain
to the implementation or use of the technology described in this
document or the extent to which any license under such rights might or
might not be available; neither does it represent that it has made any
effort to identify any such rights.  Information on the IETF's
procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11.  Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such proprietary
rights by implementers or users of this specification can be obtained
from the IETF Secretariat.

The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary rights
which may cover technology that may be required to practice this
standard.  Please address the information to the IETF Executive
Director.

8.0  Acknowledgments

This document is a product of the TN3270E Working Group.  Special thanks
are due to Derek Bolton and Michael Boe of Cisco Systems for their
numerous comments and suggestions for improving the structure of this
MIB.  Thanks also to Randy Presuhn of BMC Software for his valuable
review comments on several versions of the document.

9.0  References

[1]  Case, J., M. Fedor, M. Schoffstall, J. Davin, "Simple Network
     Management Protocol", RFC 1157, SNMP Research, Performance Systems
     International, MIT Laboratory for Computer Science, May 1990.

[2]  McCloghrie, K., and M. Rose, Editors, "Management Information Base
     for Network Management of TCP/IP-based internets: MIB-II", STD 17,
     RFC 1213, Hughes LAN Systems, Performance Systems International,
     March 1991.

[3]  Case, J., McCloghrie, K., Rose, M., and Waldbusser S., "Structure
     of Management Information for Version 2 of the Simple Network
     Management Protocol (SNMPv2)", RFC 1902, January 1996.

[4]  Case, J., McCloghrie, K., Rose, M., and Waldbusser, S., "Textual
     Conventions for Version 2 of the Simple Network Management Protocol
     (SNMPv2)", RFC 1903, January 1996.

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[5]  Case, J., McCloghrie, K., Rose, M., and Waldbusser, S.,
     "Conformance Statements for Version 2 of the Simple Network
     Management Protocol (SNMPv2)", RFC 1904, January 1996.

[6]  Case, J., McCloghrie, K., Rose, M., and Waldbusser, S., "Protocol
     Operations for Version 2 of the Simple Network Management Protocol
     (SNMPv2)", RFC 1905, January 1996.

[7]  Harrington D., Presuhn, R., Wijnen, B., "An Architecture for
     Describing SNMP Management Frameworks", RFC 2271, Cabletron
     Systems, BMC Software, Inc., IBM T.J. Watson Research, January
     1998.

[8]  Harrington D., Presuhn, R., Wijnen, B., "Message Processing and
     Dispatching for the Simple Network Management Protocol (SNMP)", RFC
     2272, Cabletron Systems, BMC Software, Inc., IBM T.J. Watson
     Research, January 1998.

[9]  Levi D., Meyer P., Stewart, B., "SNMPv3 Applications", RFC 2273,
     SNMP Research, Inc., Secure Computing Corporation, Cisco Systems,
     January 1998.

[10] Blumenthal, U., Wijnen, B., "User-based Security Model (USM) for
     version 3 of the Simple Network Management Protocol (SNMPv3)", RFC
     2274, IBM T. J. Watson Research, January 1998.

[11] Wijnen, B., Presuhn, R., McCloghrie, K., "View-based Access Control
     Model (VACM) for the Simple Network Management Protocol (SNMP)",
     RFC 2275, IBM T.J. Watson Research, BMC Software, Inc., Cisco
     Systems, Inc., January 1998.

[12] Postel, J., and Reynolds, J., "Telnet Protocol Specification", RFC
     854, May 1983.

[13] Postel, J., and Reynolds, J., "Telnet Timing Mark Option", RFC 860,
     May 1983.

[14] Rekhter, J., "Telnet 3270 Regime Option", RFC 1041, January 1988.

[15] Kelly, B., "TN3270 Enhancements", RFC 1647, July 1994.

[16] White, K. and Moore, R., "Base Definitions of Managed Objects for
     TN3270E Using SMIv2", Internet-Draft Work in progress, April 1998.

[17] IBM, International Technical Support Centers, "Response Time Data
     Gathering", GG24-3212-01, November 1990.

[18] Hovey, R., and S. Bradner, "The Organizations Involved in the IETF
     Standards Process", BCP 11, RFC 2028, October 1996.

[19] Bradner, S., "Key words for use in RFCs to Indicate Requirement
     Levels", BCP 14, RFC 2119, March 1997.

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10.0  Authors' Addresses

  Kenneth D. White
  Dept. BRQA/Bldg. 501/G114
  IBM Corporation
  P.O.Box 12195
  3039 Cornwallis
  Research Triangle Park, NC 27709, USA
  E-mail: [email-masked]

  Robert Moore
  Dept. BRQA/Bldg. 501/G114
  IBM Corporation
  P.O.Box 12195
  3039 Cornwallis
  Research Triangle Park, NC 27709, USA
  Phone: +1-919-254-7507
  E-mail: [email-masked]

11.0  Full Copyright Statement

Copyright (C) The Internet Society (1997).  All Rights Reserved.

This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it or
assist in its implementation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are included
on all such copies and derivative works.  However, this document itself
may not be modified in any way, such as by removing the copyright notice
or references to the Internet Society or other Internet organizations,
except as needed for the purpose of developing Internet standards in
which case the procedures for copyrights defined in the Internet
Standards process must be followed, or as required to translate it into
languages other than English.

The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.

This document and the information contained herein is provided on an "AS
IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK
FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT
LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT
INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE.

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