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Re: transmech MTU comments
Along with this, what if we were to set the tunnel MTU to a
value that is slightly larger than the size of the underlying
IPv4 interface (minus 20bytes for IPv4 header)? In the dynamic
case, the test could be:
- packet has ECT(0), ECT(1) codepoint - forward if smaller than
link MTU, setting to CE if necessary; dropping if too large
- packet does not have ECT(0), ECT(1) - check the IPv4 path
MTU, forward if not larger, else send ICMPv6 "packet too big"
Can something like this go as a text change suggestion for MECH?
Thanks - Fred
Erik,
My understanding of RFC 3168 is that when the tunnel interface
forwards an IPv6 packet to an IPv4 interface with an ECT(0) or ECT(1)
codepoint in the traffic class field, it MAY set the codepoint to CE if
congestion is experienced. I interpret the MAY to mean that the other
option is to drop the packet. If the packet is to be dropped, should it
be dropped silently? Also, could a link restriction be considered as
congestion? If so, does drop silent also entail NOT sending an
ICMPv6 "packet too big" message back to the source?
Thanks - Fred