Hi Satoru, ------------------ Peng Wu PhD candidate Department of Computer Science & Technology Tsinghua University, Beijing, China
>Hi Peng, > > >2011/4/20 Peng Wu <[email protected]>: >> Hi Satoru, >> >> About the item DS-Lite with no NAT or NAT on the B4, it's DS-lite without >> CGN on the AFTR. >> Generally B4 will get public IPv4 address allocated from the ISP and use it >> for IPv4 access. The AFTR will only need to maintain IPv6-IPv4 address >> mapping without port information. >> Doing this the addressing and routing between IPv6 and IPv4 are still >> independent. It's a protocol extenstion to DS-lite, and it can work along >> with DS-lite. > >So you mean that your 4over6 document is a B4NAT document, isn't it? Yes. >But I don't find any B4NAT definition in your document though. >On the other hand, I understand that you propose another 4over6 >deployment model, which you don't need to use ds-lite terminology. You >already define 4over6 initiator and concentrator, etc., So I think >that using "B4NAT" makes confusion. Like I said, the names haven't matched yet. That's the confusion. IMHO, B4NAT isn't a very formal name, right? The original words are "DS-Lite with no NAT or NAT on the B4 element", which covers the full semantic and however is quite long...That's part of the reason we use a new name. If you have any suggestions on the name, it'll be good. About 4over6 TI and TC, we use the terminology because their functions are a little different to original DS-lite, and there're cases that one would like to deploy 4over6 independently with no DS-LITE address sharing. Anyhow it's a detailed issue. > >> >> We've already present it in last three IETF meetings. See >> http://tools.ietf.org/html/draft-cui-softwire-host-4over6-04. The general >> idea is out there, and the only confusion is that the mechanism name hasn't >> matched yet. >> We'll come up with a new version with evolvement before next IETF for WG >> adoption. > >I'm confused because current ds-lite document clearly define as follow >in section 4.2: > > "A DS-Lite CPE SHOULD NOT operate a NAT function between an internal > interface and a B4 interface, as the NAT function will be performed > by the AFTR in the service provider's network. That will avoid > accidentally operating in a double NAT environment." > >And section 5.1 describes as follow: > > "5. B4 element > 5.1. Definition > > The B4 element is a function implemented on a dual-stack capable > node, either a directly connected device or a CPE, that creates a > tunnel to an AFTR." > >These mean that B4 is equal to CPE, so that B4 cannot has NAT function. >Is that correct? Well, that's why it's an extension to DS-lite, I don't see problems here. BTW, in real word, CPEs like home gateway usually support NAT functions already. _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
