Optimal Cache Budget Distribution for Hierarchical ICN Networks

Caching facilities can be deployed by all or some of the ICN nodes on the path of delivering data items from a content source to users. However, some inconsistent conclusions have been made from different studies regarding the benefits of in-network caching. To investigate the benefits of in-network caching, we propose an analytical model that optimally distributes a total cache budget among the nodes of a given ICN network in an environment that does not follow the Independent Reference Model (IRM).The cache budget distribution problem is studied with respect to optimizing system-centric and user-centric metrics, using a small number of synthetic and realistic topologies as case studies. Our findings reveal the benefits of in-network caching as well as the optimal distribution of the cache budget in ICNs with respect to our selected objective function. Although the efficiency of in-network caching on user-centric metrics strongly depends on topologies and the strength of temporal locality, in-network caching is very helpful in optimizing the ISP-centric metrics for all network and traffic settings.