COSMIC - Coding for Optimized Sending in Multimedia InterPlanetary Communication

A popular technique for enhancing Content Delivery Networks (CDNs) is leveraging the opportunities provided by Peer to Peer (P2P) networks, of which the Interplanetary File System (IPFS) is a widely used one. While IPFS tends to perform well only in homogeneous networks, performance tends to quickly deteriorate when the channel parameters of individual peers differ, which is the case in real-world scenarios. A crucial technology for facilitating the flexible distribution of data requests is Random Linear Network Coding (RLNC). The RLNC technology is leveraged by the protocol Storing coded Packets In-advance For IPFS (SPIFI). Based on SPIFI, we design and implement the Coding for Optimized Sending in Multimedia InterPlanetary Communication (COSMIC) protocol, which uses an adaptive data request scheme to fit all imaginable network configurations. We compare the performance of the three protocols, IPFS, SPIFI, and COSMIC, in tailored and random test cases. To quantify performance, we use the transmission time and transmitted overhead as our metrics. Regarding the transmission time, COSMIC beats the other protocols by at least $\mathbf{3 0 \%}$. The transmitted overhead of COSMIC is slightly worse than SPIFI, but still beats IPFS by a wide margin. For comparison, we also calculate the minimal theoretically possible transmission time in a distribution network with random parameters as a lower bound.