Protecting Multicast Sessions Against Single-Link Failure in Survivable WDM Mesh Networks

Optimal and Reliable Routing for Multicast Sessions in WDM Networks

“…The most recent work in [7] developed three heuristics that protect multicast sessions against any single link failure. The authors aimed to reduce the amount of the utilized network resources by reducing the number of branches in the multicast tree.…”

“…Constraints ( 7) and ( 8) guarantee the routing of the WPs on a tree topology for each session ses. More specifically, constraint (7) expresses that a directed graph with |N | nodes can have at most |N | − 1 directed links. Constraint (8) guarantees for every subset of nodes S of the graph that the number of directed links connecting its nodes is at most |S| − 1, which practically means that there will be no cycles in the required tree.…”

“…Constraints (9), (10) and (11) perform the routing of the BPs of every demand of each session in the exact same manner as (2), ( 3) and (4) for the WPs, respectively. Constraints ( 12) and ( 13) define which links are used for the BPs of a specific session ses, symmetrically with constraints (7) and (8), respectively. Constraints ( 14) and (15) make sure that the WP and the BP of a particular demand in each session are going to be link-disjoint in both directions of the link.…”

“…Reliability ensures that data reaches its destinations consistently, without disruption or loss, which is especially critical for real-time applications. Survivability mechanisms are essential to maintain communication even in the face of network failures, ensuring uninterrupted multicast sessions in scenarios of link or node failures, natural disasters, or deliberate attacks [7], [8], [9].…”