Virtual SANs (VSANs) are a proprietary feature of Cisco MDS 9000 switches that allows a single infrastructure to be partitioned into multiple logical SANs. This implementation is well-suited to Cisco’s large enterprise customers, who typically deploy large SAN fabrics and invest in director-class switches with high port counts. VSANs allow virtual fabrics to be configured on a single physical infrastructure, eliminating the need to physically partition the SAN. VSANs enable more robust security, availability, and scalability in FC fabrics. The preceding graphic shows an example of a single physical SAN fabric divided into two VSANs. VSANs can be used to isolate traffic based on the unique requirements of each organization:
Different customers in storage provider data centers Production and test environments in an enterprise network Low and high security requirements Backup and data replication traffic on separate VSANs Dedicated resources and bandwidth for priority applications