No abstract

Content to be transported over an Information Centric Networking (ICN) infrastructure can be very variable in size, from few bytes to hundreds of gigabytes. Therefore it needs to be segmented in smaller size data units, typically called chunks, in order to be handled by ICN nodes. A chunk is the basic data unit to which caching and security (e.g. encryption and signature) functions are applied. If we consider the overhead and the number of cryptographic operations to be performed by nodes, a good choice for the chunk size would be from hundreds of KBs up to few MBs. However, if the chunk size is bigger than the Maximum Transfer Unit of a link, chunks will be fragmented. We show that if we have more than 3-4 fragments per chunk, and congestion and reliability functions are executed on a chunk by chunk basis, the efficiency of the congestion control algorithm drastically decreases. On the other side, a small chunk size would increase overhead and rate of signature checks.The contribution of this paper is twofold: 1) we propose to segment content in two levels: at the first level the content is segmented in chunks, at the second level the chunks are segmented into smaller data units, handled by an ICN specific Transport Protocol (ICTP), performing reliability and congestion control functions; 2) we propose to adopt a receiver-driven transport protocol, in which the receiver adjusts the sending rate to control congestion, we describe an implementation of this protocol, and evaluate its performance.

-Information Centric Networking (ICN) is a new networking paradigm in which the networkprovides users with content instead of communication channels between hosts. Software Defined Networking (SDN) is an approach that promises to enable the continuous evolution of networking architectures. In this paper we propose and discuss solutions to support ICN by using SDN concepts. We focus on an ICN framework called CONET, which grounds its roots in the CCN/NDN architecture and can interwork with its implementation (CCNx). Although some details of our solution have been specifically designed for the CONET architecture, its general ideas and concepts are applicable to a class of recent ICN proposals, which follow the basic mode of operation of CCN/NDN. We approach the problem in two complementary ways. First we discuss a general and long term solution based on SDN concepts without taking into account specific limitations of SDN standards and equipment. Then we focus on an experiment to support ICN functionality over a large scale SDN testbed based on OpenFlow, developed in the context of the OFELIA European research project. The current OFELIA testbed is based on OpenFlow 1.0 equipment from a variety of vendors, therefore we had to design the experiment taking into account the features that are currently available on off-the-shelf OpenFlow equipment.

-Information Centric Networking (ICN) is a new paradigm in which the network layer provides users with content, instead of providing communication channels between hosts, and is aware of the name (or identifiers) of the contents. A fundamental ICN operation is the routing of content requests towards a node that is able to provide the requested content. To meet this goal, different routing architectures have been proposed so far.In this paper, we consider a network that uses a routing-by-name architecture, i.e. content requests are routed on the base of the content name by using a name-based routing table. We focus on the scenario of fetching Web contents, assuming to use ICN in place of traditional TCP/IP means. In this scenario we need to handle tens of billions of name-based routes, due to the high numbers of Web contents and to the limited aggregability of their names. Consequently, re-using the existing architecture of an IP router would result in two severe problems. First, the current Forwarding Information Base (FIB) technology is unable to contain all name-based routes. Second, implementing a so large Routing Information Base (RIB) requires a very costly hardware. In order to overcome these problems, we propose a routing-by-name architecture, named Lookup-and-Cache, where the FIB is used as a cache of routes, while the RIB is stored in a remote and centralized Routing Engine. By analyzing real Internet traces, we prove the effectiveness of the proposed architecture, which we also show to be feasible with current technology. In fact, our ICN nodes require to have only a limited set of routes in their FIB, even when supporting a high number of traffic flows.We have implemented our proposed Lookup-and-Cache solution within the CCNx software framework and we used this implementation to assess system performance, such as download delay, lookup rate and fairness.The paper is completed with a discussion on how ICN can be used not only to fetch Web contents but also for other scenarios.