ABNO-driven content distribution in the telecom cloud

Abstract

Abstract-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.Keywords: Datacenter interconnection, Optical networks, Content distribution. INTRODUCTIONCloud-based contents are experiencing an exponential growth in users and data volume. In [1], Cisco forecast a yearly global growth of 23% in datacenter (DC)-to-user traffic, 29% in DC-to-DC traffic, and 22% in the intra-DC traffic. Likewise, Alcatel-Lucent highlights that metro traffic will increase 560% by 2017 mainly driven by IP video and cloud traffic [2], growing two times faster than core network traffic. They conclude that placing contents in DCs closer to users can result in a 41% bandwidth reduction in the metro networks. The resulting distributed DC architecture should come together with the extension of the core network functionalities towards the metro, as proposed in [3].Robust telecom infrastructures are needed to minimize the impact of failures on the services [4]; this is especially relevant in the case of video distribution. In fact, prolonged service outages and disruptions have negatively impacted the confidence of important companies toward cloud environments. Telecom operators are in a vantage position to capitalize on highly-reliable cloud services since they o...

Restoration in Optical Cloud Networks With Relocation and Services Differentiation

“…This assumption refers to a scenario where transponders in the optical networks work at 100 Gbps, with storage units of approximatively 1.3 Gb in size. These values are in line with the assumptions presented in [18], [19]. The value of ⇥ is assumed to be equal to 2 ⇥ 10 5 [km/s], while the hop length in the NSF and Italian topology is set to 1086 and 224 km, respectively.…”