Re: [ippm] WGLC for STAMP Extensions

["MORTON, ALFRED C (AL)" <[e-mail]>]

Hi IPPM,

At one of the author’s request, I reviewed draft-ietf-ippm-stamp-option-tlv-04.

TL;DR: I have a lot of small comments; no show-stoppers I think.

regards,
Al


   MBZ Must Be Zeroed   [acm] s/Zeroed/Zero/ ? that’s the way MBZ is usually used...

...
       Figure 1: STAMP Session-Sender test packet format with TLV in
                           unauthenticated mode

   An implementation of STAMP Session-Reflector that supports this
   specification SHOULD identify a STAMP Session using the SSID in
   combination with elements of the usual 4-tuple
[acm] <insert> for the session. If the Session-Reflector finds that
the SSID and 4-tuple combination changes during a test session, then
the Session-Reflector MUST discard the non-matching packet(s) and take
no further action on them.
   .  A conforming...


...

                        Figure 5: Extra Padding TLV

   where fields are defined as the following:

   o  Extra Padding Type - TBA1 allocated by IANA Section 5.1

   o  Length - two octets long field equals length on the Extra Padding
      field in octets.

   o  Extra Padding - a pseudo-random sequence of numbers.  The field
      MAY be filled with all zeroes.
[acm] 1,$ s/zeroes/zeros/g

   The Extra Padding TLV is similar to the Packet Padding field in
   TWAMP-Test packet [RFC5357].  The Extra Padding TLV MUST be used to
   create STAMP test packets of larger size
[acm] <insert> than the usual STAMP test packet, xxx octets for un-authenticated.


...
                 Figure 6: Session-Reflector Location TLV

   where fields are defined as the following:

   o  Location Type - TBA2 allocated by IANA Section 5.1

   o  Length - two octets long field equals length on
[acm] s/on/of/
      the Value field in
      octets.
[acm] <insert> The
       Length field value MUST be 20 octets for the IPv4 address
      family.  For the IPv6 address family
[acm] <insert> ", the "
       value of the Length field
      MUST be 44 octets.  All other values are invalid.
[acm] in two places above, s/MUST be/MUST equal/
(otherwise, there is some ambiguity about length and value)

   o  Source MAC - 6 octets 48 bits long field.  The session-reflector
      MUST copy Source MAC of received STAMP packet into this field.

   o  Reserved - two octets long field.  MUST be zeroed on transmission
      and ignored on reception.

   o  Destination IP Address - IPv4 or IPv6 destination address of the
[acm] ??? packet ???  if yes, delete packet at end of sentence...
      received by the session-reflector STAMP packet.
[acm] these fixes apply below to Source IP Address

   o  Source IP Address - IPv4 or IPv6 source address of the received by
      the session-reflector STAMP packet.
...

                    Figure 7: Timestamp Information TLV

   where fields are defined as the following:

   o  Timestamp Information Type - TBA3 allocated by IANA Section 5.1

   o  Length - two octets long field, equals four octets.
[acm] , set equal to the value 4 ?  (there seems to be a lot of this!)

   o  Sync Src In - one octet long field that characterizes the source
      of clock synchronization at the ingress of Session-Reflector.

      There are several of methods to synchronize the clock, e.g.,
      Network Time Protocol (NTP) [RFC5905], Precision Time Protocol
      (PTP) [IEEE.1588.2008], Synchronization Supply Unit (SSU) or
      Building Integrated Timing Supply (BITS), or Global Positioning
      System (GPS), Global Orbiting Navigation Satellite System
      (GLONASS) and Long Range Navigation System Version C (LORAN-C).
      The value is one of the listed in Table 4.
[acm] ... one of those listed ...  (more changes like this, too)

...

4.5.  Direct Measurement TLV

   The Direct Measurement TLV enables collection of "in profile" IP
   packets that had been transmitted and received by the Session-Sender
   and Session-Reflector respectfully.  The definition of "in-profile
   packet" is outside the scope of this document.
[acm]  and left to the test operators to determine.

...

   o  Reserved - the three octest-long field.  Its value MUST be zeroed
[acm] s/octest/octets/
      on transmission and ignored on receipt.

4.8.  HMAC TLV

...

             | TBA7  |  Follow-up Telemetry  | This document |
             | TBA8  |          HMAC         | This document |
             +-------+-----------------------+---------------+
[acm] You can suggest the values, if you want.
                           Table 2: STAMP Types

...

                  +-------+-------------+---------------+
                  | Value | Description | Reference     |
                  +-------+-------------+---------------+
                  | 1     |     3GPP    | This document |
                  | 2     |   Non-3GPP  | This document |
                  +-------+-------------+---------------+
[acm] these seem overly broad, and unlikely to be extended because they *cover everything*!!
                            Table 8: Access IDs

...

              +-------+---------------------+---------------+
              | Value |     Description     | Reference     |
              +-------+---------------------+---------------+
              | 1     |  Network available  | This document |
              | 2     | Network unavailable | This document |
              +-------+---------------------+---------------+
[acm] these seem overly broad, and imply knowledge where the STAMP end-point has limited insights!!
                          Table 10: Return Codes

...

6.  Security Considerations

   Use of HMAC in authenticated mode may be used to simultaneously
   verify both the data integrity and the authentication of the STAMP
   test packets.
[acm] That's it? At least add reference to STAMP 8762 Security Section?
[acm] I suspect there will be some challenges for "Location" in future


From: ippm [mailto:[e-mail]] On Behalf Of Ian Swett
Sent: Friday, May 22, 2020 5:26 PM
To: IETF IPPM WG ([e-mail]) <[e-mail]>
Subject: [ippm] WGLC for STAMP Extensions

Hi IPPM,

At our virtual interim meeting, we decided draft-ietf-ippm-stamp-option-tlv was ready for last call. This email starts a two-week WGLC for this draft.

The latest version can be found here: https://tools.ietf.org/html/draft-ietf-ippm-stamp-option-tlv-04<https://urldefense.proofpoint.com/v2/url?u=https-3A__tools.ietf.org_html_draft-2Dietf-2Dippm-2Dstamp-2Doption-2Dtlv-2D04&d=DwMFaQ&c=LFYZ-o9_HUMeMTSQicvjIg&r=OfsSu8kTIltVyD1oL72cBw&m=-FQ_7VkardtUOemNdXjWGCdxDzw_8jcaV16Ots-GfRo&s=zadhVvE6IwVbJd0BcDUJdpX4xXqA4i60susVdbT5Pvg&e=>

This last call will end on Monday, June 8th. Please reply to [e-mail]<mailto:[e-mail]> with your reviews and comments.

Thanks,
Ian & Tommy