There are many posts about MPLS Traffic Engineering with RSVP on the Website, in this post we will look at the alternative approaches to the MPLS TE with RSVP. MPLS Traffic Engineering has some drawbacks as well. IP Fast Reroute Mechanisms can be seen as successful alternative to MPLS Traffic Engineering if you are using MPLS TE for only fast convergence purpose. One of the main drivers for the MPLS Traffic Engineering is explicit path routing.
We can define the desired path from Ingress tunnel router explicitly.If packet needs to go from New York to Seattle , you can send it to Amsterdam even :). RSVP ( Resource Reservation Protocol ) is used to allocate label and Link-state routing protocols ( OSPF and IS-IS ) are used to advertise link attributes such as metric, available, used and unreserved bandwidth or link colouring in the context of MPLS Traffic Engineering.
In 2013 Cisco,Ericsson, Google and couple other big companies published a draft about Segment Routing which is alternative method to established explicit path without using RSVP or any separate label distribution protocol. Conclusion : Segment routing is an alternative method to MPLS Traffic Engineering for creating explicit path routing, IP Fast Reroute mechanisms are alternative methods to MPLS TE for fast rerouting.
It’s Your Turn
Do you think that Segment Routing is a revolution?. Or did you hear it first time here ? Share your insights and feelings about it in the comments box below.