Procket

GMPLS is a rather natural outgrowth from the traffic engineering MPLS application. MPLS gives us a connection-oriented service that operates in parallel with our connectionless service (IP). We use this because controlling the path of the traffic is key to the ability to run a network at much higher utilization levels. The ability to shift traffic from a hotspot to spare capacity is simply a boon to the folks who are actually designing and operating networks.

From there, it's only a small hop to see that the ability to engineer a lambda path is conceptually identical to setting up an MPLS LSP. Both are simply connection routing and signaling applications.

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