Over and above the default username concurrency controls of the Session State Register, the Optional Concurrency and Wholesale Module provides expanded capabilities to track user concurrency using any user attribute.
Concurrency on any attribute is only supported when SBR Carrier is running as part of a Session State Register cluster. This feature is not supported on a standalone SBR Carrier server.
RADIUS Class Attributes are an optional part of the RADIUS standard, but not all network access devices fully support attributes. In order to work at the RADIUS server level, the network NADs must support the Radius Class Attribute. If they do not, the attribute data the server requires is not created.
As with username-based concurrency, you can set a limit on the maximum number of concurrent connections that a user can have. SBR Carrier servers in the cluster compare the number of active connections for a particular string attribute up to the maximum limit each time a new connection is requested.
If a new connection exceeds the limit, Session State Register may reject or allow the additional connection. In either case, the event is logged in the server log.
When counting connections, Session State Register does not distinguish between multi-link connections and new authentication attempts.