Last Call Review of draft-ietf-dhc-dhcp4o6-saddr-opt-04

Request Review of draft-ietf-dhc-dhcp4o6-saddr-opt
Requested rev. no specific revision (document currently at 08)
Type Last Call Review
Team General Area Review Team (Gen-ART) (genart)
Deadline 2018-09-07
Requested 2018-08-24
Authors Ian Farrer, Qi Sun, Yong Cui, Linhui Sun
Draft last updated 2018-09-06
Completed reviews Genart Last Call review of -04 by Elwyn Davies (diff)
Secdir Last Call review of -04 by Brian Weis (diff)
Genart Telechat review of -05 by Elwyn Davies (diff)
Assignment Reviewer Elwyn Davies 
State Completed
Review review-ietf-dhc-dhcp4o6-saddr-opt-04-genart-lc-davies-2018-09-06
Reviewed rev. 04 (document currently at 08)
Review result Ready with Nits
Review completed: 2018-09-06


I am the assigned Gen-ART reviewer for this draft. The General Area
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Document: draft-ietf-dhc-dhcp4o6-saddr-opt-04
Reviewer: Elwyn Davies
Review Date: 2018-09-06
IETF LC End Date: 2018-09-07
IESG Telechat date: Not scheduled for a telechat

Summary: Ready with nits. Thanks - well written and almost all quite clear.

Major issues:

Minor issues:
>    o  The received bindprefix6-len value is not larger than the number
>       of bytes, divided by 8, received in the bind-ipv6-prefix field.
>       (e.g. the bindprefix6-len is 128 but the bind-ipv6-prefix field is
>       only 8 bytes long).
Given that s6.1 gives a deterministic algorithm for calculating the length of the bind-ipv6-prefix field, I don't understand why the validation does not check that the length of the field is exactly as specified by this algorithm rather than using it as a lower limit.

s7.5 and s8 (last para): Given that the time constraints and number of retries will interact and are implemented in different devices, I think these two values need some sensible defaults defined so that devices from different sources should interoperate successfully out of the box.

Nits/editorial comments:
General: s/e.g./e.g.,/g

Abstract, sentence 2: Introduce DHCP 4o6 abbreviation: s/For DHCPv4 over DHCPv6/For DHCPv4 over DHCPv6 (DHCP 4o6)/.

Abstract: Add mention of RFC 6346 and RFC 7598 for explanation of softwire scheme.

Abstract, para 2: Expand ORO (Option Request Option) and give ref to rfc3315bis.

s1, para 3:  s/attached to any routable IPv6 prefix/attached to a network segment using any routable IPv6 prefix/

s4, para 1: It would be useful to remind readers of the expansion of BR in OPTION_S46_BR:  Maybe s/the remote IPv6 address for the softwire/the remote IPv6 address used for the softwire border router/

s4, para 1: Expand ULA (not a well-known abbreviation).

s7.2.1, para 1: 'flash' is colloquial and may not be generally understood.  I think it can safely be removed.

s7.4, para after bullets: s/For either of these cases,/If either check fails,/

s10: To be absolutely clear, there are two instances where the following change ought to be made:
in the table at
in the Option Codes table at