Next Generation CDN Services for Community Networks

Abstract

Abstract-Technological developments of the last few years have favoured the creation of distributed networking infrastructures (usually referred to as Community Networks) where the resources are made available to the members of a community of people. With emerging large-scale community infrastructures the opportunities for new commercial services and for innovative business models are becoming feasible. Since one of the most resource-demanding services today is access to user-generated content through the web, suitable content delivery services are needed in the context of Community Networks in orders to make an effective usage of shared resources.In this paper we describe two architectures we have designed to provide optimized delivery of multimedia web content (e.g. video but also other kinds of User Generated Content) within Community Networks. Both architectures work without any kind of cooperation from the original content providers but assume that a basic web caching service is provided within the network, either by commercial Service Providers or by the community members themselves.While the first architecture relies on a traditional centralized control entity, the second is designed according to the peer-topeer paradigm, in order to provide better scalability, robustness to failures and self-configurability. Experimental results are also presented aimed at evaluating the performance gains for endusers from a localized distribution of content in scenarios in which community members are distributed in clusters sparse at different geographic locations.

Energy efficiency and traffic offloading in wireless mesh networks with delay bounds

“…Equations (5) and (6) are the flow conservation constraints (see the following details for a brief explanation), Equation (7) imposes that each UT u retrieves the content c from exactly one GW, that is that there is a single source for each demand .c; u/, Equation (8) imposes that each UT must be assigned to exactly one GW, Equations (9) and (10) impose that, if a GW is powered off, no UT or GW can be connected to it, Equation (11) imposes that no content can be retrieved from a powered-off GW and Equations (12) and (13) impose that the average waiting times in the GW-UT and GW-GW interfaces do not exceed a predefined bound. The next section illustrates how (12) and (13) have been obtained.…”

“…As for the delay aspect, we set d U = 50 ms and d G = 50 ms. Consequently, the delay that is introduced by the CDWMN should be, at most, in the order of 100 ms, which is generally suitable for most multimedia contents. For the H parameter, we have obtained an upper bound by performing the same experiments described in Section 4.2 using the capacity constraints (24)-(25) (see the following details) in place of the delay bounds (12)- (13) and then by extracting the 99-percentile of the average hop count. The resulting value is H D 1:095.…”

“…[11,12]). Remarkably, there have already been also attempts at merging the CDN and mesh paradigms towards the common goal of EE, as exposed for example in [13,14].Given these premises, we build our work on the system architecture that arises from joining the WLAN access system with the CDN and the mesh paradigms. Specifically, we address a Content-Delivery Wireless Mesh Network (CDWMN), that is a WLAN in which the GWs, besides granting Internet access to the user terminals (UTs), are also able to perform (limited) content caching and to handle wireless multi-hop paths.…”

The greening potential of content delivery in residential community networks

“…Manetti et al [8] designed a centralised and a peer-topeer architecture to deliver contents in community networks. However, the focus of the work is mostly on the protocol design and content indexing aspects, with no mention to the power consumption issues.…”

“…(6) and (7) are the flow conservation constraints (see below for a brief explanation), Eq. (8) impose that each UT u retrieves the content c from exactly one GW (single source of demand ðc; uÞ), Eq. (9) impose that each UT must be assigned to exactly one GW, Eqs.…”