Joint Content-Resource Allocation in Software Defined Virtual CDNs

A software defined virtual CDN (SDvCDN) is a virtual cache network deployed fully in software over a programmable cloud network infrastructure that can be elastically consumed and optimized using global information about network conditions and service requirements. We formulate the joint content-resource allocation problem in SDvCDNs as a minimum cost mixed-cast flow problem with resource activation decisions. Our solution jointly optimizes the placement and routing of content objects along with the allocation of the required virtual storage and transport resources, is applicable to arbitrary network topologies, and captures activation and operational costs, content popularity, unicast and multicast delivery, as well as capacity and latency constraints. We present preliminary results for the general mixed integer linear programming solution, as well as conditions for polynomial solvability. The value of our approach goes beyond the optimization of SDvCDNs, as it provides an efficient methodology to jointly address placement (facility location), routing (network flow) and resource allocation (network design/embedding) problems.