1. A method of configuring data storage in a data storage subsystem for restricting access of host processors to the data storage, said method comprising: a) subdividing the data storage into addressable logical storage units; and b) assigning to each host processor a respective subset of the data storage to which access of said each host processor is restricted; wherein the assignment of at least one respective subset includes at least one vector specification of a series of the addressable logical storage units, the addressable logical storage units in the series of addressable logical storage units having addresses that form a vector, the vector including a beginning address (BEGIN) and a stride (S) that is a difference between neighboring addresses of the addressable logical storage units in the series of addressable logical storage units, such that the addresses of the logical storage units in the series are BEGIN, BEGIN&plus;S, BEGIN&plus;2S,..., and wherein the stride (S) is a non-zero integer different from one.