On the fundamental limits of coded caching and exact-repair regenerating codes

The fundamental limits are investigated for (i) the problem of coded caching with N = 3 files and K = 3 users, and (ii) the problem of (5; 4; 4) exact-repair regenerating codes, i.e., there are n = 5 storage nodes where any k = 4 nodes can be used to recover the data, and any failed node can be repaired with d = 4 other nodes. A computational approach is adopted in this investigation which was developed by the author in an earlier work. For the first problem, an improved outer bound to the memory-delivery-rate tradeoff is obtained. For the second problem, a complete characterization of the storage-repair-bandwidth is provided. These results are part of the online collection of “Solutions of Computed Information Theoretic Limits (SCITL)”.