... is immutable and therefore asin-gleavailablecopy is sufficient to retrieve the correct object), we compute the follo wing values for. =P (objectois unavailable) =P (allkreplicasofo are unavailable) =P (one replica is unavailable) k = (1 a) k which upon solving fork yields k= log log(1 a) (1) 2.2 **ErasureCoding** ...

The network coding inspired methods basically outperform **erasure coding** in terms of downloading time for an object availability target, as well as in repair bandwidth needs. 2.1 **ErasureCoding** Distributed Storage Systems In a distributed storage system employinga (N,M) erasure code[10], each ...