NDProxy Update draft-thaler-ipv6-ndproxy-02.txt

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NDProxy Updatedraft-thaler-ipv6-ndproxy-02.txt

• Dave ThalerMohit TalwarChirayu Patel

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Status

• http//www.icir.org/dthaler/NDProxyIssues.htm
• All issues from before last IETF closed
• New editorial issues submitted
• Say when bridging is sufficient (Pekka Savola)
• Add examples to protocol guidelines (Pekka
  Savola)
• New technical issues submitted
• AH removal (Pekka Savola)
• Segments with differing MTUs (Chirayu Patel)
• IPv4 support (Chirayu Patel)

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Issue 12 AH removal

• Removing AH from a proxied packet may cause a
  packet to be dropped due to security policy
• SEND doesnt use AH, so proxied packets wont
  have AH anyway
• Change in -02 remove all mention of AH removal

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Issue 13 Segments with differing MTUs

• Previously had non-goal to support segments with
  different MTU
• But 1 of the 2 scenarios (PPP upstream) has
  different MTUs
• Previously said NDproxy added/updated MTU option
  when proxying RA in scenario 2
• but this can cause failure if adding doesnt fit

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Issue 13 (cont)

• RFC 2461 section 4.6.4 says about this case
• If the bridges do not generate ICMP Packet Too
  Big messages, communicating nodes will be unable
  to use Path MTU to dynamically determine the
  appropriate MTU on a per-neighbor basis. In such
  cases, routers use the MTU option
• Change in -02
• NDproxy generates Packet Too Big Message
• Remove all mention of modifying RAs

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Issue 10 IPv4 support

• Should IPv4 support be left in or removed?
• Draft discusses NDproxy in terms of IPv6 neighbor
  cache states
• Draft -02 just adds For readability, we will
  describe the neighbor cache as if both IPv4 and
  IPv6 neighbors use the same state machine
  described in ND.
• IPv4 support comes mostly for free with the above
  caveat
• Options
• Leave it with the above caveat
• Remove all mention of IPv4 support
• Put IPv4 support in an appendix

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Other comments?
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Issue 11 Say when bridging is sufficient

• Response
• Already says bridging should be used except where
  it can't work, and enumerates the two cases where
  it doesn't. 
• Hence, every scenario which has neither
  limitation is a bridging scenario.
• Proposed resolution reject as out of scope