A New NS2 Module for the Simulation of MPLS Networks with Point-to-Multipoint LSP Support

Nowadays, many IP backbone networks adopt separate control and forwarding planes for unicast and multicast traffic flows. Indeed, while MPLS (multiprotocol label switching) is widely deployed for unicast traffic, IP multicast is the only available solution for the delivery of "one-to-many" traffic flows. With P2MP LSPs (point-to-multipoint label switched paths) support, a unified control and forwarding plane may be devised. Such a reduction in the number of protocols used in the core of the network as well as in the number of encapsulations in the data plane, results in simplified network operations. The paper discusses the design and the development of the control and data planes extensions needed to provide P2MP LSP support in an MPLS node. In particular, such extensions, concerning the P2MP LSPs path computation, the RSVP-TE signalling protocol, and the forwarding mechanism, have been implemented as new software modules for an ad-hoc developed simulator, based on NS2. Finally, tests have been performed to assess the behaviour of the new functionalities introduced in the simulator.