Representability of matroids and locally repairable codes
Vortrag von Prof. Dr. Ragnar Freij
Sprecher eingeladen von: Prof. Dr. Joachim Rosenthal
Datum: 15.12.14 Zeit: 13.00 - 14.00 Raum: UNINE, B217
The ever growing need for more efficient and larger scaled systems for data storage has made distributed storage an increasingly important ingredient in many data systems. In such distributed storage systems, it is desirable that data can be reliably stored over a network of nodes so that the data can can be retrieved even if some nodes fail. One class of repair efficient codes for node failures is locally repairable codes (LRCs). In this talk we will present some new results on linear LRCs constructed from expander graphs and from a special class of matroids, known as gammoids. Moreover, we will show how matroid theory gives bounds on the rate/locality/distance tradeoffs, for almost affine LRCs, and as a special case for linears LRCs.The talk is based on a joint work with Thomas Westerbäck, Toni Ernvall and Camilla Hollanti.