Subject: Bug in / Fix for tn3270eRtDataTable in <draft-ietf-tn3270e-r

From: Robert Moore <[email-masked]>
Date: Mon, 1 Jun 1998 16:50:32 -0400

As promised, I'm recapping for the list a discussion we had
at the interim WG meeting at the TIE this morning.  Briefly,
I reported a bug we found in the tn3270eRtDataTable as we were
testing our management software in preparation for the TIE,
and I proposed a solution.  The people present in the room
indicated their agreement with this solution, but it needs to
go to the mailing list as well.  Hence this note.

THE PROBLEM:

Currently the tn3270eRtDataTable is indexed by

    { tn3270eSrvrConfIndex,
      tn3270eClientGroupName,
      tn3270eRtDataClientAddrType,
      tn3270eRtDataClientAddress }

Given this indexing, there is no way to have multiple entries
for a single client IP address, even if there are multiple
clients there, each with its own Telnet session to the server.
(This configuration, which people agreed was a common one in
practice, is achieved by having each client use a different
ephemeral port on the client host.)  This limitation defeats
the goal of setting the aggregation bit to false, i.e., of
instructing the server not to aggregate the response time
data for the clients in the group.  From the beginning the
understanding has been that this setting instructs the
server to create a separate tn3270eRtDataEntry for each of
the clients in the group.  But the existing four-part index
for the tn3270eRtDataTable doesn't allow this when there are
multiple clients at a single IP address.

THE SOLUTION:

Extend the index for the tn3270eRtDataTable to:

    { tn3270eSrvrConfIndex,
      tn3270eClientGroupName,
      tn3270eRtDataClientAddrType,
      tn3270eRtDataClientAddress,
      tn3270eRtDataClientPort },

where the last element of this index is a new object added
to the tn3270eRtDataTable.  In addition to making it possible
for the server to honor the false setting for the aggregation
bit, this new index will make it possible for a management
application to correlate an entry in this table with one in
the tn3270eTcpConnTable in the base TN3270E MIB, which can in
turn provide useful information for diagnosis of response time
problems.

PROPOSED SCHEDULE:

Unless there are objections from the mailing list, I'm planning
to update the TN3270E-RT-MIB document with this new index
object by next Monday (June 8).  The people present at the TIE
agreed that if a new draft is available by then, the WG should
be able to go ahead and forward it and the existing draft of
the base MIB to the IESG next week for consideration for
Proposed Standard.

Regards,
Bob

Bob Moore
IBM Networking Software
+1-919-254-4436
[email-masked]