This read-only Integer32 identifies the virtual system (vsys) on a NetScreen firewall/security appliance to which a row of WebUI admin settings applies, and it also serves as the table's index. An admin managing a multi-tenant NetScreen box with several virtual systems uses this value to tell which vsys a given set of web-management settings (timeout, port, SSL cipher, etc.) belongs to when walking the nsSetWebUICfgTable. For example, a value of 0 might represent the root system while a nonzero value like 3 identifies a specific customer vsys with its own WebUI configuration. Since it is the table index, each distinct vsys produces its own row in nsSetWebUICfgTable.