> -----邮件原件----- > 发件人: Isis-wg [mailto:[email protected]] 代表 joel jaeggli > 发送时间: 2014年5月5日 23:55 > 收件人: Acee Lindem; Xuxiaohu; George, Wes > 抄送: [email protected]; [email protected]; [email protected]; > [email protected]; [email protected] > 主题: Re: [Isis-wg] [sunset4] IPv6 router IDs > > On 5/5/14, 9:28 AM, Acee Lindem wrote: > > Xiaohu – what are precisely the situations that you think you need > > this > > IPv6 address? > > Acee > > if you're using router-id's as equivalency as an ipv4 unicast addresses. > you're doing so at your peril because there is zero assurance that those > actually > map. the first time you have a router id of > 11100000000000000000000000000101 well bummer.
The IPv6 router ID sub-TLV of the ISIS router capability TLV must carry a "routable" IPv6 address. If the name of the sub-TLV seems confusing, it can be changed to IPv6 address sub-TLV. Best regards, Xiaohu > I don't find the embedding of semantic meaning in router-ids to be more > compelling then it was in ip addresses. > > > From: Xuxiaohu <[email protected] <mailto:[email protected]>> > > Date: Sunday, May 4, 2014 1:29 AM > > To: "George, Wes" <[email protected] > > <mailto:[email protected]>> > > Cc: OSPF - OSPF WG List <[email protected] <mailto:[email protected]>>, > > "[email protected] <mailto:[email protected]>" <[email protected] > > <mailto:[email protected]>>, "[email protected] > > <mailto:[email protected]>" <[email protected] > > <mailto:[email protected]>>, "[email protected] > > <mailto:[email protected]>" <[email protected] > > <mailto:[email protected]>>, "[email protected] > <mailto:[email protected]>" > > <[email protected] <mailto:[email protected]>> > > Subject: Re: [Isis-wg] [sunset4] IPv6 router IDs > > > > Hi Wes, > > > > > > > > Thanks for pointing out these two drafts. > > > > > > > > The motivation for these two drafts > > (http://tools.ietf.org/html/draft-xu-isis-ipv6-router-id-00 and > > http://tools.ietf.org/html/draft-xu-ospf-ipv6-router-id-00) is very > > simple: the IPv6 ISIS|OSPF capability TLV/RI-LSA which are used for > > advertising router capabilities can be flooded across areas, > > however, only a 4-octect router ID is carried in them. As a result, > > it’s hard for routers in one area to establish correlations between > > IPv6 addresses and capabilities of routers in another area. For > > example, assume IS-IS router A in one area has established a L3VPN > > session with IS-IS router B in another area over their own IPv6 > > addresses. When router A needs to send L3VPN traffic to router B via > > a MPLS-SR tunnel, router A wants to know whether router B has the > > ELC (http://tools.ietf.org/html/draft-xu-isis-mpls-elc-00) before > > <http://tools.ietf.org/html/draft-xu-isis-mpls-elc-00)%20before> > > inserting an EL into the MPLS-SR packet . However, the Capability > > TLV originated by router B doesn’t carried an IPv6 address of its > > own. As a result, it’s hard for router A to know the ELC of router B. > > > > > > > > Best regards, > > > > Xiaohu > > > > > > > > *发件人:*George, Wes [mailto:[email protected]] > > *发送时间:*2014年5月2日1:51 > > *收件人:*Xuxiaohu > > *抄送:*[email protected] <mailto:[email protected]>; > > [email protected] <mailto:[email protected]>; > > [email protected] <mailto:[email protected]> > > *主题:*Re: [sunset4] IPv6 router IDs > > > > > > > > I got a bounce-back on all 3 draft aliases, trying again with the > > authors’s email addresses directly. > > > > > > > > *From: *<George>, "George, Wes" <[email protected] > > <mailto:[email protected]>> > > *Date: *Thursday, May 1, 2014 at 1:42 PM > > *To: *"[email protected] > > <mailto:[email protected]>" > > <[email protected] > > <mailto:[email protected]>>, > > "[email protected] > > <mailto:[email protected]>" > > <[email protected] > > <mailto:[email protected]>> > > *Cc: *"[email protected] > > <mailto:[email protected]>" > > <[email protected] > > <mailto:[email protected]>>, > > "[email protected] <mailto:[email protected]>" <[email protected] > > <mailto:[email protected]>> > > *Subject: *[sunset4] IPv6 router IDs > > > > > > > > I see that you have submitted two drafts for IPv6 router IDs in ISIS > > and OSPF, noting that the existing router ID is only 4 octets. This > > has also come up in IDR for BGP. The authors of that draft are > > copied. I’ll give you a similar set of feedback to what I gave > > them - > > > > > > > > It is important to distinguish between places where a unique > > identifier is needed, and by *convention* an IPv4 address assigned > > to the device has been used to provide that unique ID, vs. places > > where the actual IP address has some sort of importance to the > > protocol (I.e. That information must be available to take action on). > > > > In other words, is the protocol requirement that the ID be unique > > across some domain, but that the actual value does not matter, or is > > the protocol requirement that the value must correspond to something > > on the router? In many of the former cases, the fact that the value > > isn’t relevant has been used to make recommendations that are easier > > for humans to deal with (I.e. Tying the router ID to an IP address) > > but that value as a human-readable set of info does not necessarily > > justify changes to the protocol to support that convention as we > > move to IPv6. > > > > I would argue that the router ID used in routing protocols must > > merely be unique, but it doesn’t have to be an IP address at all. > > Thus it is not strictly necessary to create a new field to carry > > IPv6 addresses when operating without IPv4 addresses on a network. > > If you believe otherwise, the justification needs to be documented > > in the draft. > > > > > > > > There are many places in IETF protocols where a 32 bit unique > > identifier is needed, and by convention an IPv4 address has been > > used. It would be far more useful to write a general draft > > identifying this problem and discussing several solutions, including > > simply generating unique IDs manually, systematically generating a > > random ID, etc. the place for such a draft may be in Sunset4, > > either as a part of the existing gap analysis draft or as another > > standalone draft. > > > > > > > > There was rather a long discussion about this on IDR, thread > > here: > > https://mailarchive.ietf.org/arch/search/?qdr=a&email_list=idr&q=%22%5 > > Bidr%5D+%5Bv6ops%5D+BGP+Identifier%22&as=1&gbt=1 > > > > > > > > And in the IDR meeting, minutes: > > > > http://www.ietf.org/proceedings/89/minutes/minutes-89-idr (see > > page 11) > > > > > > > > I’d encourage the authors of these drafts to work together on this. > > > > > > > > Thanks, > > > > > > > > Wes George > > > > > > > > Anything below this line has been added by my company’s mail server, > > I have no control over it. > > > > ----------- > > > > > > > > > > ---------------------------------------------------------------------- > > -- > > > > This E-mail and any of its attachments may contain Time Warner Cable > > proprietary information, which is privileged, confidential, or > > subject to copyright belonging to Time Warner Cable. This E-mail is > > intended solely for the use of the individual or entity to which it > > is addressed. If you are not the intended recipient of this E-mail, > > you are hereby notified that any dissemination, distribution, > > copying, or action taken in relation to the contents of and > > attachments to this E-mail is strictly prohibited and may be > > unlawful. If you have received this E-mail in error, please notify > > the sender immediately and permanently delete the original and any > > copy of this E-mail and any printout. > > > > > > > > _______________________________________________ > > sunset4 mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/sunset4 > > > _______________________________________________ OSPF mailing list [email protected] https://www.ietf.org/mailman/listinfo/ospf
