The MPLS-OPS Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] RE: IGP
He means where you use static LSP's that have been generated/calculated via some offline method. By offline this means some system that is not part of the routing system. ie some network management software running on a PC or mainframe. There was a good draft rfc "draft-liljenstolpe-tewg-cwbcp-01.txt" that was from a Cable & Wireless person, that had a very good reasons to do this. Not sure if the draft is still around as it expired june 2002. If it can't be found I can mail interested parties a copy. > Mathew, would you go into a bit more detail on what you mean by "off- > line traffic engineering"? If you reference has me stumped, I'll bet > there are others out there with the same question. > > Thanks much. > > Roger Williams > > At 06:25 PM 7/8/2002, you wrote: > At 08:25 AM 7/5/2002 -0500, Christopher Lewis wrote: > Plain MPLS or MPLS VPN will work fine with distance vector protocols > like EIGRP, but as mentioned a link state routing protocol is needed > for MPLS traffic engineering, as each node needs the topology > information those protocols provide and OSPF and IS-IS have the > opaque LSA extensions necessary for traffic engineering. > > To add to Chris' comments, note that this is for online "on the > router" traffic engineering only. If you're doing off-line traffic > engineering, any routing protocol that allows the control plane to > operate will do. > > Three benefits that offline TE offers vs. OSPF/IS-IS TE: > 1) You can implement a routing algorithm that does a lot better than > Dijkstra shortest path. For example, you can minimize overall network > utilization and avoid bottlenecks. > 2) You can pre-calculate and install backup LSPs and ensure that > there are no single points of failure, thereby dramatically improving > LSP restoration time and guaranteeing resiliency. > 3) You can support LSP constraints that are non-additive in nature -- > since shortest path works by adding hop metrics. > > Cheers, > > Mathew > > ------------------------------------------------------------------------- Simeon Pilgrim 27 Nazareth Avenue Software Engineer PO Box 8011 Allied Telesyn Research Christchurch 8034 phone: +64 3 339 3000 New Zealand fax: +64 3 339 3001 ------------------------------------------------------------------------- ------- The MPLS-OPS Mailing List Subscribe/Unsubscribe: http://www.mplsrc.com/mplsops.shtml Archive: http://www.mplsrc.com/mpls-ops_archive.shtml
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