On Sun, 14 May 2000, Danny McPherson wrote:
If it were actually implemented it wouldn't be something you'd hand to the NOC .. unless I'm missing something. You don't hand them your SPF algorithm, or your BGP decision algorithm .. it's
Good point. I assume you would calculate and precompute offline and have the results loaded into the router. Some implementations already use something like this in case of fast online restoral. (Fore is one if I remember correctly. They calculate 4 next best paths in case of failure of the primary).
The benefit of a circuit-based restoration mechanism (i.e. MPLS fast reroute with a pre-defined backup LSP) is that when you switch to a backup connection you know (with some level of confidence) that packets forwarded on the connection will not be tossed around like hot potatos until the entire IGP converges, SPF calculation throttles are reset, etc.., introducing instability in the network.
Understand what you were saying now. /vijay