Abstract
This paper presents several fault-tolerant simulations of a single-writer multi-reader regular register in storage systems. One simulation tolerates fail-stop failures of storage servers and require a majority of nonfaulty servers, while the other simulation tolerates Byzantine failures and requires that two-thirds of the servers to be nonfaulty. A construction of Afek et al. [2] is used to mask semi-Byzantine failures of clients that result in erroneous write operations. The simulations are used to derive Paxos algorithms that tolerate semi-Byzantine failures of clients as well as failstop or Byzantine failures of storage servers.