You are changing the forwarding plane of a L3 service and as such this is not implementable in merchant silicon so far. You need a flexible network processor to do this and I am not sure about the performance implications. So why I am against this draft is because it has a big impact on the data-plane. The fundamental difference between the proposals is that you have on egress a mapping in the label that determines the forwarding behaviour to be applied, rather than having to check src/dst IP matches + LPM lookups.
On 27/11/13 02:31, "Xuxiaohu" <[email protected]> wrote: >Fine. In my draft, both intra-subnet and inter-subnet IP traffic are >forwarded at layer3 while in the draft you mentioned below only >inter-subnet traffic would be forwarded at layer3. They are totally >different approaches and therefore it's meaningless to say which one is >easier or not. > >Xiaohu > >> -----邮件原件----- >> 发件人: Henderickx, Wim (Wim) [mailto:[email protected]] >> 发送时间: 2013年11月25日 19:16 >> 收件人: Xuxiaohu; [email protected] >> 抄送: [email protected] >> 主题: Re: 答复: 答复: 答复: New Version Notification for >> draft-xu-l3vpn-virtual-subnet-02.txt >> >> Lets debate the technical solutions iso blogs. >> >> On 25/11/13 08:52, "Xuxiaohu" <[email protected]> wrote: >> >> >I suggest you read the following blog post by Yakov >> >(http://opencontrail.org/why-contrail-is-using-bgpmpls/). >> > >> >> -----邮件原件----- >> >> 发件人: Henderickx, Wim (Wim) >> [mailto:[email protected]] >> >> 发送时间: 2013年11月25日 15:27 >> >> 收件人: Xuxiaohu; [email protected] >> >> 抄送: [email protected] >> >> 主题: Re: 答复: 答复: New Version Notification for >> >> draft-xu-l3vpn-virtual-subnet-02.txt >> >> >> >> There are easier ways to do this which don’t required data-plane >> >>changes. >> >> >> >>https://tools.ietf.org/html/draft-sajassi-l2vpn-evpn-inter-subnet-forw >> >>ard >> >>in >> >> g-02 >> >> >> >> On 25/11/13 07:40, "Xuxiaohu" <[email protected]> wrote: >> >> >> >> > >> >> > >> >> >> -----邮件原件----- >> >> >> 发件人: Henderickx, Wim (Wim) >> >> [mailto:[email protected]] >> >> >> 发送时间: 2013年11月25日 14:29 >> >> >> 收件人: Xuxiaohu; [email protected] >> >> >> 抄送: [email protected] >> >> >> 主题: Re: 答复: New Version Notification for >> >> >> draft-xu-l3vpn-virtual-subnet-02.txt >> >> >> >> >> >> It is not about TTL 1, no TTL decrement should happen for >> >> >>intra-subnet forwarding at all On top you need to modify the >> >> >>data-plane to achieve this, since it now needs to find out if it >> >> >>is intra or inter subnet where current PE(s) don’t have to do >>this. >> >> > >> >> >Sure, it needs some change to the implementation of PE routers. >> >> >That's why we need a draft to specify the implementation >>requirements. >> >> > >> >> >> On 25/11/13 07:22, "Xuxiaohu" <[email protected]> wrote: >> >> >> >> >> >> >Wim, >> >> >> > >> >> >> >It said clearly "if the source and destination addresses of a >> >> >> >packet whose TTL is set to 1 belong to the same extended subnet, >> >> >> >both ingress and egress PE routers MUST NOT decrement the TTL of >> >> >> >such packet." Did you doubt that the PE routers could know >> >> >> >whether the source and destination address belong to the same >> extended subnet? >> >> >> > >> >> >> >Xiaohu >> >> >> > >> >> >> >> -----邮件原件----- >> >> >> >> 发件人: Henderickx, Wim (Wim) >> >> >> [mailto:[email protected]] >> >> >> >> 发送时间: 2013年11月25日 14:08 >> >> >> >> 收件人: Xuxiaohu; [email protected] >> >> >> >> 抄送: [email protected] >> >> >> >> 主题: Re: New Version Notification for >> >> >> >>draft-xu-l3vpn-virtual-subnet-02.txt >> >> >> >> >> >> >> >> On the TTL issue I believe this is not addressing the issue. We >> >> >> >>can say don’t decrement but when and how will the PE(s) do or >> >>don’t. >> >> >> >> >> >> >> >> On 25/11/13 03:22, "Xuxiaohu" <[email protected]> wrote: >> >> >> >> >> >> >> >> >Hi all, >> >> >> >> > >> >> >> >> >Major changes since the -01 version include: >> >> >> >> > >> >> >> >> >1) add a section about TTL consideration; >> >> >> >> >2) remove the section of PE Router FIB Reduction; >> >> >> >> >3) remove the section of PE Router RIB Reduction; >> >> >> >> > >> >> >> >> >Any further comments are welcome. BTW, the removed sections as >> >> >> >> >mentioned above would be described in separate docs. >> >> >> >> > >> >> >> >> >Best regards, >> >> >> >> >Xiaohu >> >> >> >> > >> >> >> >> >> -----邮件原件----- >> >> >> >> >> 发件人: [email protected] >> >> >> >> >>[mailto:[email protected]] >> >> >> >> >> 发送时间: 2013年11月25日 10:10 >> >> >> >> >> 收件人: Brendan Fee; Susan Hares; Fan Yongbing; Xuxiaohu; >> >> >> >> >>Xuxiaohu; Christian Jacquenet; Truman Boyes; Yongbing Fan >> >> >> >> >> 主题: New Version Notification for >> >> >> >> >>draft-xu-l3vpn-virtual-subnet-02.txt >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> A new version of I-D, draft-xu-l3vpn-virtual-subnet-02.txt >> >> >> >> >> has been successfully submitted by Xiaohu Xu and posted to >> >> >> >> >>the IETF repository. >> >> >> >> >> >> >> >> >> >> Filename: draft-xu-l3vpn-virtual-subnet >> >> >> >> >> Revision: 02 >> >> >> >> >> Title: Virtual Subnet: A L3VPN-based Subnet Extension >> >>Solution >> >> >> >> >> Creation date: 2013-11-25 >> >> >> >> >> Group: Individual Submission >> >> >> >> >> Number of pages: 13 >> >> >> >> >> URL: >> >> >> >> >> >> >> >> >>http://www.ietf.org/internet-drafts/draft-xu-l3vpn-virtual-subne >> >> >> >>t-0 >> >> >> >>2.t >> >> >> >>xt >> >> >> >> >> Status: >> >> >> >> >>http://datatracker.ietf.org/doc/draft-xu-l3vpn-virtual-subnet >> >> >> >> >> Htmlized: >> >> >> >> >>http://tools.ietf.org/html/draft-xu-l3vpn-virtual-subnet-02 >> >> >> >> >> Diff: >> >> >> >> >> >> >> >> >> >>http://www.ietf.org/rfcdiff?url2=draft-xu-l3vpn-virtual-subne >> >> >> >> >>t-0 >> >> >> >> >>2 >> >> >> >> >> >> >> >> >> >> Abstract: >> >> >> >> >> This document describes a Layer3 Virtual Private Network >> >> >>(L3VPN)- >> >> >> >> >> based subnet extension solution referred to as Virtual >> >> >> >> >> Subnet, >> >> >> >>which >> >> >> >> >> can be used as a kind of Layer3 network virtualization >> >>overlay >> >> >> >> >> approach for data center interconnect. >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> Please note that it may take a couple of minutes from the >> >> >> >> >>time of submission until the htmlized version and diff are >> >> >> >> >>available at tools.ietf.org. >> >> >> >> >> >> >> >> >> >> The IETF Secretariat >> >> >> >> > >> >> >> > >> >> > >> > >
