A Virtualized, Programmable Content Delivery Network

In this paper, we present an open platform of content delivery networks (CDNs), namely vCDN, by which a wide range of delivery strategies can be dynamically deployed via a centralized controller and a pool of geographically dispersed cloud resources. A control application can be written for representing a specific strategy w.r.t required scale, responsiveness, and security in content delivery, and then translated into a virtualized delivery network, a form of an overlay network on cloud storages and virtual machines. In doing so, we explore the unique combination of named data networking (NDN), software defined networking (SDN), and distributed monitoring so as to achieve to a certain extent programmability in content delivery. Different from traditional CDNs, the strategy of content delivery in vCDN is not statically fixed but can be tailored by each service provider via the deployment of its own control application. Throughout a few applications running on our test bed at 7 geographical locations with multiple cloud resources, we demonstrate the feasibility of the programmable CDN and the delivery performance enhancement by inter-cloud network route managements.