Distributed Partial Information Management ( DPIM ) Framework for Survivable Networks ∗

This paper describes a novel framework called Distributed Partial Information Management (or DPIM). It addresses several major challenges in achieving efficient shared path protection under distributed control with only partial information, including (1) how much partial information about existing active and backup paths (or APs and BPs respectively) is maintained and exchanged; (2) how to obtain a good estimate of the bandwidth needed by a candidate BP, called BBW, and subsequently select a pair of AP and BP for a connection establishment request so as to minimize total bandwidth consumption and/or maximize revenues; (3) how to distributively allocate minimal BBW (and de-allocate maximal BBW) via distributed signaling; and (4) how to update and subsequently exchange the partial information. Two DPIM schemes, one using Integer Linear Programming (ILP) and the other using a heuristic to find a pair of AP and BP, as well as several possible information exchange methods based on the modifications or extensions to existing IP-based routing protocols, are proposed. The performances of the two DPIM schemes are shown to be much better than an existing ILP-based scheme requiring about the same amount of partial information. In addition, the trade-offs between the performance and information exchange frequency are also studied, and an efficient information exchange method is identified. The paper also presents an elegant way to support dynamic requests for protected, unprotected, and pre-emptiable connections in the unified DPIM framework.