Sensing Content Correlation-aware In-network Caching Scheme at the Edge for Internet of Things

Existing caching schemes process content objects (COs) individually based on the exact matching without considering the semantic correlation among content objects. We argue that this approach is inefficient in the Internet of Things (IoT) due to the highly redundant nature of IoT device deployments and the data accuracy tolerance of IoT applications. Therefore, the cache of a different CO having a high semantic correlation with another requested one by an application can be reused if the CO meets the data accuracy requirement of the application. In this case, caching both COs is inefficient. This paper extends the concept of cache hit and proposes a caching scheme considering the semantic content correlation of nodes to evaluate, construct, and enable the re-usability of available cached items to serve more diverse requests based on information correlation. For demonstrating its benefits, we implement the proposed scheme on the top of LFU (Least Frequently Used) for IoT data caching at the edge. Obtained experimental results show that the proposed scheme achieves a significant cache hit ratio improvement in comparison with LFU.