> -----邮件原件----- > 发件人: Peter Psenak [mailto:[email protected]] > 发送时间: 2014年1月29日 17:24 > 收件人: Xuxiaohu > 抄送: [email protected]; [email protected] > 主题: Re: [spring] [OSPF] fwd: New Version Notification for > draft-xu-ospf-global-label-sid-adv-00.txt > > Xuxiaohu, > > On 1/29/14 10:16 , Xuxiaohu wrote: > > > > > >> -----邮件原件----- > >> 发件人: Peter Psenak [mailto:[email protected]] > >> 发送时间: 2014年1月29日 17:11 > >> 收件人: Xuxiaohu > >> 抄送: [email protected]; [email protected] > >> 主题: Re: [spring] [OSPF] fwd: New Version Notification for > >> draft-xu-ospf-global-label-sid-adv-00.txt > >> > >> Xiaohu, > >> > >> On 1/29/14 09:53 , Xuxiaohu wrote: > >>> For example, assume a label block {1000, 1999} is allocated for > >>> prefix > >> segments by almost all SR routers and a global label 1005 is > >> allocated to a given prefix segment, for a given seldom SR router > >> which couldn't preserve the above label block and allocates a > >> different label block (e.g., {2000, 2999}) instead, a local label > >> corresponding to that global label (or that prefix segment) could be > >> calculated through offsetting, i.e., the result is 1005+ > >> (2000-1000)=2005. In this way, there is no need for introducing the > >> Index concept anymore and therefore the architecture becomes much > >> easy to understand. More importantly, compared to the index binding > >> advertisement, the label binding advertised by the IGP is exactly the > >> same as that in the label forwarding table for those most SR routers > >> which have allocated the above common label block, which is much > beneficial when doing troubleshooting. This approach does not violate the > strongest MPLS dogma (i.e., labels MUST be local) while! > >> taking in > >> to account the actual situation, IMHO > >> > >> above would require the "seldom SR router" to know the offset from > >> the SRGB used by other routers. How do you envision that to be learned? > > > > Hi Peter, > > > > I don't think it's a big problem. The common SRGB could either be manually > configured on the seldom SR router or advertised by the MS. > > manual configuration is not an option - just imagine you have multiple "seldom > SR routers", each having a different label block. Now you not only need an > offset for "common" block, but also offset between label blocks used on these > "seldom SR routers".
Peter, Why do you need offset between label blocks used on these seldom SR routers? The common block is the only frame of reference, IMO. > Once you start to advertise it, you are back to the model we have already, but > you made it even worse with offsets. I don't think so. Take the above situation as an example, in the index binding mode, you could allow the most SR routers to advertise its label range starting with zero to achieve the above effect (although it conflicts with the definition of label range). However, for the seldom SR router, what label range should it advertise? Best regards, Xiaohu > regards, > Peter > > > > > Best regards, > > Xiaohu > > > >> regards, > >> Peter > >> > >>> > >>> Best regards, > >>> Xiaohu > > _______________________________________________ OSPF mailing list [email protected] https://www.ietf.org/mailman/listinfo/ospf
