If we can predict that many new extension headers will be defined in the future,a new draft for the router to recognize the newly defined extension header will be neccessary.For example,we can define a set of parameters including the Next Header value in the immediately preceding header,a list of the format of probable options,the extension headers that might be placed before the newly defined extension header,and the probable actions of the router when meeting the extension header.The purppose of the parameters likes the feature of virsus. So future implementations can recognize any extension header.
----- Original Message ----- From: "Bob Hinden" <[EMAIL PROTECTED]> To: "Suresh Krishnan" <[EMAIL PROTECTED]> Cc: <[email protected]> Sent: Friday, October 20, 2006 4:06 AM Subject: Re: New draft on IPv6 extension headers > Suresh, > > [No hats on] > >> Hi Folks, >> I have submitted a draft requesting a standard format for IPv6 >> extension headers. I would appreciate any comments on it. > > I really like reading clear and concise drafts!!! Thanks! > > While I agree that the problem that your draft is addressing is real, > I think in practice your proposal won't have very much effect on > fixing the problem. This will address new IPv6 extention headers > defined in the future, but it won't address other new protocols that > are defined that might show up after an IPv6 header, nor will it > address the ones that have been defined in the past. The result is > that a node that wants to parse all of the headers will still have to > still know about each one. It will even have to know that it is a > new IPv6 extension header that has this format. There is no bit or > flag that identifies an IPv6 extension header. > > Also, for devices like firewalls the security implications of > skipping unknown (except for their format) headers isn't very good. > > Finally, I think it is too late to be redefining the fragmentation > header. > > Bob > > p.s. I hope this draft doesn't mean that someone is thinking of > defining a lot of new IPv6 extension headers.... :-) > > >> Thanks >> Suresh >> >> >> -------- Original Message -------- >> Subject: I-D ACTION:draft-krishnan-ipv6-exthdr-00.txt >> Date: Wed, 18 Oct 2006 15:50:02 -0400 >> From: [EMAIL PROTECTED] >> Reply-To: [EMAIL PROTECTED] >> To: [email protected] >> >> A New Internet-Draft is available from the on-line Internet-Drafts >> directories. >> >> >> Title : Format for IPv6 extension headers >> Author(s) : S. Krishnan >> Filename : draft-krishnan-ipv6-exthdr-00.txt >> Pages : 8 >> Date : 2006-10-18 >> >> In IPv6,optional internet-layer information is encoded in separate >> headers that may be placed between the IPv6 header and the >> transport >> layer header. There are a small number of such extension headers >> currently defined. This document defines a format for defining new >> IPv6 extension headers. >> >> >> A URL for this Internet-Draft is: >> http://www.ietf.org/internet-drafts/draft-krishnan-ipv6-exthdr-00.txt >> >> To remove yourself from the I-D Announcement list, send a message to >> [EMAIL PROTECTED] with the word unsubscribe in the body of >> the message. >> You can also visit https://www1.ietf.org/mailman/listinfo/I-D-announce >> to change your subscription settings. >> >> Internet-Drafts are also available by anonymous FTP. Login with the >> username "anonymous" and a password of your e-mail address. After >> logging in, type "cd internet-drafts" and then >> "get draft-krishnan-ipv6-exthdr-00.txt". >> >> A list of Internet-Drafts directories can be found in >> http://www.ietf.org/shadow.html >> or ftp://ftp.ietf.org/ietf/1shadow-sites.txt >> >> Internet-Drafts can also be obtained by e-mail. >> >> Send a message to: >> [EMAIL PROTECTED] >> In the body type: >> "FILE /internet-drafts/draft-krishnan-ipv6-exthdr-00.txt". >> >> NOTE: The mail server at ietf.org can return the document in >> MIME-encoded form by using the "mpack" utility. To use this >> feature, insert the command "ENCODING mime" before the "FILE" >> command. To decode the response(s), you will need "munpack" or >> a MIME-compliant mail reader. Different MIME-compliant mail readers >> exhibit different behavior, especially when dealing with >> "multipart" MIME messages (i.e. documents which have been split >> up into multiple messages), so check your local documentation on >> how to manipulate these messages. >> >> Below is the data which will enable a MIME compliant mail reader >> implementation to automatically retrieve the ASCII version of the >> Internet-Draft. >> >> >> -------------------------------------------------------------------- >> IETF IPv6 working group mailing list >> [email protected] >> Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 >> -------------------------------------------------------------------- > > > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > [email protected] > Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
