Cryptography in Hierarchical Coded Caching: System Model and Cost Analysis

The idea behind network caching is to reduce network traffic during peak hours via transmitting frequently-requested content items to end users during off-peak hours. However, due to limited cache sizes and unpredictable access patterns, this might not totally eliminate the need for data transmission during peak hours. Coded caching was introduced to further reduce the peak hour traffic. The idea of coded caching is based on sending coded content which can be decoded in different ways by different users. This allows the server to service multiple requests by transmitting a single content item. Research works regarding coded caching traditionally adopt a simple network topology consisting of a single server, a single hub, a shared link connecting the server to the hub, and private links which connect the users to the hub. Building on the results of Sengupta et al. (IEEE Trans. Inf. Forensics Secur., 2015), we propose and evaluate a yet more complex system model that takes into consideration both throughput and security via combining the mentioned ideas. It is demonstrated that the achievable rates in the proposed model are within a constant multiplicative and additive gap with the minimum secure rates.

Automated summary

Network caching aims to reduce network traffic during peak hours by transmitting frequently-requested items to end users during off-peak hours. Coded caching further reduces peak hour traffic by sending coded content that can be decoded in different ways by different users. Research works in this area typically use a simple network topology, but more complex systems combining throughput and security considerations have shown promising results in achieving rates close to minimum secure rates.