Contrary to TCP’s inherent location-dependency, Information-Centric Networking (ICN) architectures employ a receiver-driven model where (i) receivers request content by its name, (ii) in an asynchronous and (iii) connectionless (stateless) manner. Hence ICN architectures are mobile-friendly by design, as mobile receivers can re-send requests for content not received after handing over to other locations, without any need for re-establishing a point-to-point connection. Nevertheless, there are still issues with respect to delay and jitter as well as the demand for lossless transmission of data during a mobile’s disconnection period, crucial for applications with strict performance requirements such as real-time emergency notification services, multimedia streaming and event notification services.
We present Selective Neighbor Caching (SNC), a seamless mobility enhancement solution for ICN architectures to appear in the upcoming ICN’12 workshop, which will take place in Helsinki, Finland in conjunction with the ACM SIGCOMM 2012 conference, in August 2012. SNC is an approach that aims exactly at minimizing the delay in receiving data experienced by mobiles after handing off to another network location. In order to do so, SNC defines and minimizes a target cost function which captures the tradeoff between delay and caching costs.
To satisfy the above delay optimization criterion, SNC exploits the knowledge inferred by information requests issued by mobile nodes due to the receiver-driven model in ICN. Moreover, it leverages the knowledge of users’ mobility behavior. Unlike other proactive caching approaches which blindly cache items at every cache available, SNC defines a simple, decentralized and distributed procedure for selecting only an appropriate subset of neighboring proxies, i.e. proxies lying one hop away from a mobile’s last known network location, responsible for handling information requests on behalf of mobiles, pre-fetching and proactively caching desired information items matching the mobiles’ requests while the latter remains disconnected during the hand-off phase.