Content routing and lookup schemes using global bloom filter for content-delivery-as-a-service

Leveraging cloud computing technology, we have proposed content-delivery-as-a-service (CoDaaS) to distribute user generated content (UGC) in an efficient and economical fashion. However, due to the exponential increases of Internet traffic, traditional hashing-based content routing and lookup scheme suffers from high delay. This paper introduces a global compressed counting bloom filter (CCBF) into CoDaaS to address this issue. The global CCBF adds our system with the capability to early check the existence of any specific content among all the peering surrogates, before any local checking on each cache node. Using this global CCBF, we propose two content routing and lookup mechanisms (parallel and cut-through schemes) to reduce the delay for better user experience. We verify the comparative performance of those approaches via both mathematical modeling and experimental simulation. The results show that for light traffic load, the mean response time can be saved by up to 65.2%. Besides, the impacts and overheads of different synchronization schemes for the CCBF are quantified to provide valuable insights for further optimizations.