Subject: [trill] draft-ietf-trill-ia-appsubtlv-05.txt - Shepherd's review

From: "Susan Hares" <[email-masked]>
Date: Fri, 2 Oct 2015 17:12:29 -0400

Shepherd's review:  draft-ietf-trill-ia-appsubtlv-05

Authors: Donald Eastlake and Yizhou Li 

Status: Major concern on complexity of AFN template concepts.  This concern
has been expressed to authors who will revise the draft.  The text for the
AFN Template is covered in Section 2 and section 3. 

Note: IANA previewed section 5, and agreed to it.  

Minor Technical issues: none 

Editorial issues

#1 Abstract:

Current  

   This document specifies a TRILL (Transparent Interconnection of Lots

   of Links) IS-IS application sub-TLV that enables the reporting by a

   TRILL switch of sets of addresses such that all of the addresses in

   each set designate the same interface (port) and the reporting for

   such a set of the TRILL switch by which it is reachable.

New suggested: 

   This document specifies a TRILL (Transparent Interconnection of Lots
   of Links) IS-IS application sub-TLV that enables the reporting by a
   TRILL switch of sets of addresses.  Each set of addresses reports
   addresses the same interface (port) and the TRILL switch by which it 
   reachable.

#2 - Section 2 - paragraph 1 p. 5 

Please enumerate or point to where the enumeration of the types of
addresses. 

#3 Section 2 - page 6 

Current: 

 Addr Sets End: The unsigned integer offset of the byte, within the  IA
APPsub-TLV value part, of the last byte of the last Address  Set. This will
be the byte just before the first sub-sub-TLV if  any sub-sub-TLVs are
present (see Section 3). If this is equal to  Length, there are no
sub-sub-TLVs. If this is greater than Length or points to before the end of
the Template, the IA APPsub-TLV is corrupt and MUST be discarded. This field
is always two bytes in size.

New 

Addr Sets End: The unsigned integer offset of the byte, within the IA
APPsub-TLV value part, of the last byte of the last Address  Set. This byte
will be the byte just before the first sub-sub-TLV if  any sub-sub-TLVs are
present (see Section 3). The processing is as follows:

.         If this is equal to  Length, there are no sub-sub-TLVs. 

.         If this is greater than Length or points to before the end of the
Template, the IA APPsub-TLV is corrupt and MUST be discarded. 

.         Note: This field is always two bytes in size.

#3 - page 7 paragraph 3 

        N: Notify flag: When a TRILL switch receives a new IA APPsub-

            TLV (one in an ESADI-LSP fragment with a higher sequence

            number or a new message of some other type) and the N bit is

            one, the TRILL switch then checks the contents of the

            APPsub-TLV for address sets including both an IP address and

            a MAC address.  For each such address set it finds, a

            gratuitous ARP [RFC826] or spontaneous Neighbor

            Advertisement [RFC4861], depending on whether the IP address

            is IPv4 or IPv6 respectively, may be sent. In both cases,

            these are sent out all the ports of the TRILL switch

            offering end station service and are in the VLAN or FGL of

            the address set information, that is, are Appointed

            Forwarder for the VLAN or for the VLAN to which the FGL

            maps.

What needs changing: 

Old: /and are in the VLAN or FGL of/

New: /which are in the VLAN or FGL of/  - I believe the dependent "which"
clause is more appropriate here.