ABNO-driven content distribution in the telecom cloud

As current sustained traffic growth is expected to strain capacity of today’s metro network, novel content distribution architectures where contents are placed closer to the users are being investigated. In that regard, telecom operators can deploy datacenters (DCs) in metro areas, thus reducing the impact of the traffic going from users to DCs. However, effective solutions to distribute contents to those metro DCs and to synchronize contents among them need to be investigated. In this paper, a hierarchical content distribution architecture for the telecom cloud is investigated: core DCs placed in geographically distributed locations, are interconnected through permanent “per content provider” (CP) virtual network topology (CP-VNT); additionally, metro DCs are placed close to users, and need also to be interconnected with the core DCs. CP’s data is replicated in the core DCs through the CP-VNT, while metro-to-core (M2C) anycast connections are established periodically for metro DCs to synchronize contents. Since failures in the interconnection network might disconnect the CP-VNTs, in this paper recovery mechanisms are proposed to reconnect topologies and anycast connections. Topology creation, anycast provisioning and recovery problems are first formally stated and modelled as Integer Linear Programs (ILP). Solving these models, however, becomes impractical for realsized scenarios, so heuristic algorithms are also proposed. Exhaustive simulation results show that the investigated architecture provides significant improvements in both supported traffic and restorability compared to the case of a single core DC. Workflows to implement the algorithms within the Applications-based Network Operations (ABNO) architecture and extensions for PCEP are proposed. Finally, the architecture is experimentally validated in our ABNObased iONE test-bed.