Subject: [Technical Errata Reported] RFC5453 (5589)

From: RFC Errata System <[email-masked]>
Date: Wed, 2 Jan 2019 13:51:36 -0800 (PST)

The following errata report has been submitted for RFC5453,
"Reserved IPv6 Interface Identifiers".

--------------------------------------
You may review the report below and at:
http://www.rfc-editor.org/errata/eid5589

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Type: Technical
Reported by: Brian Carpenter <[email-masked]>

Section: 3

Original Text
-------------
   +-----------------------------------------+-------------------------+
   |        Interface Identifier Range       |       Description       |
   +-----------------------------------------+-------------------------+
   |           0000:0000:0000:0000           |  Subnet-Router Anycast  |
   |                                         |        [RFC4291]        |
   |                                         |                         |
   | FDFF:FFFF:FFFF:FF80-FDFF:FFFF:FFFF:FFFF | Reserved Subnet Anycast |
   |                                         |    Addresses[RFC2526]   |
   +-----------------------------------------+-------------------------+

                       Table 1: Current Assignments

Corrected Text
--------------
   +-----------------------------------------+-------------------------+
   |        Interface Identifier Range       |       Description       |
   +-----------------------------------------+-------------------------+
   |           0000:0000:0000:0000           |  Subnet-Router Anycast  |
   |                                         |        [RFC4291]        |
   |                                         |                         |
   | FDFF:FFFF:FFFF:FF80-FDFF:FFFF:FFFF:FFFF | Reserved Subnet Anycast |
   | FFFF:FFFF:FFFF:FF80-FFFF:FFFF:FFFF:FFFF |    Addresses[RFC2526]   |
   +-----------------------------------------+-------------------------+

                       Table 1: Current Assignments

Notes
-----
Both these ranges are in fact reserved by Section 2 of RFC2526. Under current recommendations [RFC7217] the FDFF range is no longer recommended for routine use, and the FFFF range is equally likely to occur in a pseudo-random 64-bit IID. Credit to Kerry Lynn for pointing this out.

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-------------
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--------------------------------------
RFC5453 (draft-ietf-6man-reserved-iids-03)
--------------------------------------
Title               : Reserved IPv6 Interface Identifiers
Publication Date    : February 2009
Author(s)           : S. Krishnan
Category            : PROPOSED STANDARD
Source              : IPv6 Maintenance
Area                : Internet
Stream              : IETF
Verifying Party     : IESG

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From: Fernando Gont <[email-masked]>
Date: Wed, 2 Jan 2019 21:54:08 -0300

On 2/1/19 18:51, RFC Errata System wrote:

[....]
> Corrected Text

How should we make this into the actual IANA registry?

> Both these ranges are in fact reserved by Section 2 of RFC2526. Under current recommendations [RFC7217] the FDFF range is no longer recommended for routine use, and the FFFF range is equally likely…

The FDFF range still seems to be recommended for routine use of its
intended usage (i.e., anycast) -- that's why we are avoiding it in e.g.
RFC7217.

OTOH, the FFFF range wasn't present in the IANA registry, and might be
being employed for pseudo-random-IIDs.

Thoughts?

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: [email-masked]
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492

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From: Brian E Carpenter <[email-masked]>
Date: Thu, 3 Jan 2019 14:52:02 +1300

> How should we make this into the actual IANA registry?

Well, first some higher authority would have to approve the erratum.
Then I'm pretty sure the AD could simply ask IANA to make the update.

Another interesting question is who will instruct implementers
of RFC7217 to add a check for this case.

> RFC721> 

Yes, but it's a pretty unlikely problem. I think if we fix the text
and IANA registry now, it's really not going to affect the real world
much.

Rgds
   Brian

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From: Fernando Gont <[email-masked]>
Date: Wed, 2 Jan 2019 23:57:35 -0300

> of RFC7217 to add a check for this case.

I can help socialize this in at *BSD and Linux. Maybe even provide a patch.

Thanks,

---

From: Suresh Krishnan <[email-masked]>
Date: Thu, 3 Jan 2019 04:03:44 +0000

On Jan 2, 2019, at 9:57 PM, Fernando Gont <[email-masked]<mailto:[email-masked]>> wrote:

[....]
Corrected Text
--------------

Thanks Fernando. I have raised a potential issue with this range in the 6man discussion thread on this topic. I would like the discussion there to wrap up, and I can push the buttons based on what the WG concludes.

Regards
Suresh