Exact Algorithm to Solve the Minimum Cost Multi-Constrained Multicast Routing Problem

Abstract

The optimal solution of the multi-constrained QoS multicast routing problem is a tree-like hierarchical structure in the topology graph. This multicast route contains a feasible path from the source node to each of the destinations with respect to a set of QoS constraints while minimizing a cost function. Often, it is a tree. In other cases, the hierarchies can return several times to nodes and links of the topology graph. Similarly to Steiner problem, finding such a structure is an NP-hard problem. The usual tree and topology enumeration algorithms applied for the Steiner problem cannot be used to solve the addressed problem. In this paper, we propose an exact algorithm based on the Branch and Bound principle and improved by the Lookahead technique. We show relevant properties of the optimum hierarchy permitting efficient pruning of the search space. To our knowledge, our paper is the first to propose an exact algorithm for this non-trivial multi-constrained optimal multicast route computation. Simulations illustrate the efficiency of the proposed pruning operations. The analysis of the execution time shows that in simple topologies and with tight QoS constraints the exact algorithm requires relatively little execution time. With loose constraints the computation time cannot be tolerated even for off-line route computation. In these cases, the solution is close to a Steiner tree and heuristics can be applied. These results can serve as basis for the design of efficient, polynomial-time routing algorithms.

Multi-Source Reliable Multicast Routing with QoS Constraints of NFV in Edge Computing

“…Multicast routing in NFV have started to attract more and more interest of late [27][28][29][30]. Xu et al [27] aimed to minimize the cost for every multicast request or maximize the network throughput for a request sequence.…”

“…They proposed a 2K approximation algorithm based on the assumption that all VNFs in a service chain are placed on the same server. Molnar et al [28] considered the problem of QoS guarantee in the hierarchical structure of the network.…”

“…In terms of communication forms, multicast can be divided into three categories: one-to-many communication, many-to-one communication , and many-to-many communication. Currently, almost all the multicast studies focus on one-to-many communication mode [27][28][29][30]. However, in practice, there are still quite a lot of application scenarios belonging to many-to-many communication.…”

Practical Routing Protocol Models to Improve Network Performance and Adequacy

“…In this paper, the performance of routing protocols for selected network and the optimum way of utilizing the network resources is proposed, unlike [9] where an exact algorithm based on the Branch and Bound principle is proposed and then improved by the Lookahead technique.…”