Simon, >>> Med: The rationale we adopted in this draft is as follows: >>> >>> * there are three major flavors: full stateful, full stateless, and binding >>> mode >>> * all these modes can support assigning a full or a shared IPv4 address >> >> now you got me thinking, are these really the right modes from a CPE >> perspective? >> >> let me try to explain, with my CPE implementor hat on, what "modes" would >> make sense? >> >> - NAT placement. do I need a NAT on the CPE or not? >> (no NAT && no IPv4 address == DS-lite) >> - full IPv4 address assigned. >> I can assign the IPv4 address to the tunnel endpoint interface, and use >> that address for >> local applications, and as the outbound address of the NAT >> (mechanisms: MAP, Public 4over6) >> - IPv4 prefix assigned: >> I need to disable the CPE NAT, and use the assigned IPv4 prefix as my LAN >> side DHCPv4 pool >> (mechanism: MAP) >> - Shared IPv4 address. >> I must enable a local NAT, I cannot assign the IPv4 address on the "WAN" >> interface, but only use it >> for the outbound side of the NAT. > > Interesting... But note that even just implementing MAP alone would generate > three of these "implementation modes". I would still like to see this list > added to an "implementation considerations" section. Stuff like "you can't > assign a partial address to a tunnel interface" may not be obvious to > implementers. > >> then there might be a sub-modes for "tunnel endpoint determination" i.e. how >> to determine an IPv6 tunnel end point address given an IPv4 destination >> address and port. >> 1) algorithmic (MAP) >> 2) configured (Public 4over6, LW46, DS-lite) >> >> and a sub-mode for IPv4 address configuration: >> 1) As "native IPv4" >> (Public4over6, LW46) >> 2) Embedded Address >> (MAP) >> 3) None >> DS-lite >> >> does this make sense? > > Totally appropriate for an "implementation considerations" section IMHO.
I'm suggesting to replace the current drafts "state*, binding modes" with these modes. cheers, Ole _______________________________________________ Softwires mailing list Softwires@ietf.org https://www.ietf.org/mailman/listinfo/softwires
