The figure shows an example of a company network in which cache memory is divided into three virtual caches, each allocated to a different branch office. Although the host at branch office A accesses the storage system frequently, its available cache capacity is limited to 40 GB, preventing its read and write data from consuming the entire cache. Regardless of the data access volume at branch office A, the hosts at the other branch offices always have 40 GB of cache available. As a result, data transfer performance at the other branch offices is not affected by the workload at branch office A.