At the time when I was writing my MPLS books and developing MPLS courses for Cisco, everyone was ecstatically promoting GMPLS (Generalized MPLS) as the next unifying technology of everything, making someone so fed up with the fad that he wrote the Electricity over IP RFC.
GMPLS got implemented in high-end routers, but never really took off (at least I’ve never seen or even heard about it). Obviously the transport teams found the idea of routers requesting on-demand lambdas with IP-based protocols too hard to swallow.
Few years ago, ITU-T tried to reinvent the wheel (and ride on the MPLS brand name) and started the T-MPLS effort. After a while, IETF and ITU-T managed to sort out the paperwork (including plenty of liaison notes) and started joint MPLS-TP task group and new standardization efforts.
The first MPLS-TP RFCs have already started to appear and there are numerous drafts in the pipeline, so it’s high time to take a second look at MPLS-TP and figure out what’s new and whether it’s a useful technology. I tried to do that in the MPLS and MPLS Transport Profile (MPLS-TP): The technology differences article published by SearchTelecom.