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Peer to Peer (P2P) systems, have been identified as one of the main contributors to the exponential growth of internet traffic. File sharing applications such as BitTorrent clients, are the most popular among P2P systems and tend to consume great amounts of network resources, stretching infrastructure capabilities to their limits. This causes interdomain links to be overloaded with traffic, created from content traversing the network, which is most of the times redundant. Cloud computing has been an empowering force towards alleviating this issue and many research approaches have been proposed. With cloud orchestration frameworks and Software Defined Networks (SDN) as our empowering technologies, we propose a cross-layered edge-caching mechanism to alleviate content and service providers of link-saturation problems, caused by identical content requested and downloaded by multiple users in the same network vicinity. The proposed mechanism identifies and classifies P2P data-in-transit, caches it locally and successively acts as a peer by sharing it with all other requesting users. This way, redundant traffic in the backhaul link is minimized, since requests for content cached by the mechanism, will be served by the target edge-node and not from the content provider. To validate the performance and overall efficacy of the proposed mechanism, simulation experiments were conducted under a controlled-conditions environment. Results indicated that the proposed mechanism can reduce redundant network traffic up to 22%.

The application of virtualisation techniques in communication networks is growing in response to continuous pressure due to profitability stagnation and profit margin reduction. In this regard, the trend of Network Function Virtualisation (NFV), which refers to the use of cloud-based software for carrying out network functions, is expected to modify this scenario. The EU FP7 T-NOVA project has the goal of providing mechanisms to foster the adoption of NFV. In this paper, we present a look in the commercialisation of NFV-based offerings through a marketplace, in which users can trade, auction, select and acquire NFV services. In this respect, a brokering mechanism was developed that is able to facilitate competition among Function Providers (FPs), allowing the T-NOVA customers to search for available offerings, trade between the third-party function developers (FPs) and finally the Service Provider (SP) to find the best price for the VNFs, which will be part of each T-NOVA Network Service.

In this paper, we present how we could benefit from the transmitted data of a broadcast link in order to achieve optimized performance of P2P content distribution. In this context, the paper elaborates on a prototype broadcast-aware P2P mechanism (namely BAP2P) that assists content distribution among users located in different CMNs by minimising redundant traffic in the downlink stream, thus providing enhanced scalability and optimised performance. The mechanism is evaluated based on ‘Download Completion Time’ and the ‘Block exchanged’ over the DVB-T network and the results indicate the validity of the Mechanism presented.

MPEG-DASH is the first international standardisation effort in the area of HTTP Adaptive Streaming, but as its vendor counterparts suffers from the QoE unfairness issue: alike MPEG-DASH users, sharing the same net and requesting the same video service, receive segments from different Quality Profiles. Being interested to exploit MPEG-DASH paradigm for transferring video services over interactive digital broadcasting networks, we discuss, in this paper, how these broadcasting networks can provide QoE fairness to their MPEG-DASH users. In more detail, we propose the elevation of the broadcasting networks' edge routers to QoE fairness nodes able to enforce any QoE fairness policy to their MPEG-DASH users. Towards validating our approach, we integrated in each edge router a Traffic Shaper, to be used as a QoE fairness module, and run several experiments that verified the QoE unfairness issue, besides revealing ours solution capacity to eliminate it.

In this paper, we show how Active Window Management (AWM) technique can be exploited for providing QoE fairness to the HTTP Adaptive Streaming users of an interactive digital broadcasting network. Furthermore, we test AWM's efficiency against another QoE fairness provision solution, presented in other research efforts, namely the Traffic Shaping. Towards these, we firstly describe the deployment of AWM and Traffic Shaping software modules in each intermediate node (Cell Main Node-CMN) of the broadcasting network and secondly we proceed with the experimental evaluation. The experimental results showed not only AWM's efficiency to achieve the set fairness goal but also revealed AWM's capacity, when compared to Traffic Shaping, to provide for much lower TCP Round Trip Times (88% less) and zero retransmissions; a result which could, in principle, lead to less TCP rate variations and thus less Quality Profile fluctuations.