Time-Constrained Content Delivery in Multicast-Capable Optical Networks

In this paper, we study the problem of time-constrained multicast flow aggregation in which programs with specified starting times and specified ending times are aggregated together and delivered from a head end to one or more destinations. We first use a four-partite graph to describe the problem and show that the problem is NP-complete. We then formulate the problem as an integer linear program (ILP) and give results for small scale problems. A heuristic approach, named time compatible first (TCF), is presented, and results show that TCF achieves good results in both large and small scale problems.