Performance comparison of caching strategies for information-centric IoT

In-network caching is one of the most defining aspects of Information-Centric Networking (ICN). It ensures that relevant content is readily available across the network, even if the original producer is not reachable. However, in the Internet of Things (IoT), where memory is often severely limited, nodes cannot simply cache any and all content they receive, necessitating an increased reliance on caching strategies that offer heuristics on when to cache incoming content and which cached content to replace when the cache is full. In this paper, we discuss several existing ICN caching and cache replacement strategies as well as metrics suitable for evaluating them in an IoT context. We then evaluate multiple different strategies using IoT devices in a large testbed. Our experimental results show that simple stateless caching policies can perform equally well or sometimes even better than other, more complex schemes. This result is encouraging as it implies that it is indeed possible to employ effective ICN caching even in resource-constrained IoT nodes. To the best of our knowledge, this paper is the first to perform such an evaluation using actual IoT hardware in a realistic deployment.