Adaptability of Breadcrumbs Routing to Geographical Locality of Content Popularity in Information Centric Networks

In Information-Centric Networking (ICN), different routing and caching schemes have been proposed to efficiently utilize in-network caches and reduce network traffic. Most of them assume that the popularity distribution of user-requested content is homogeneous. However, the actual popularity distribution measured on the Internet is reported to possess spatial and temporal localities, which can heavily affect caching performance in ICN. Breadcrumbs (BC) routing is a key solution to mitigate performance degradation due to spatial locality because of its ability to flexibly discover cached contents in the off-path. In this paper, we deeply investigate the spatial effects of BC by revealing where utilized cached contents are located, how BC discovers these contents, what kind of contents are found, and how BC fill in the locality gap of content popularity. We also focus on another time-dimension perspective, i.e., the temporal locality of content popularity, and conduct a comprehensive study of how BC routing can be adapted to the spatiotemporal locality of content popularity in ICN.