A count based license can be dynamically floated and shared among the SBC in a network licensing mode. It also allows the enforcement of the number of sessions purchased in local and network licensing modes.
The SBC supports three license modes:
Legacy Mode: The Licenses are encoded to a unique SBC instance based on system information to a particular SBC and this is an xml-based SBC license model.
Legacy licensing mode is only supported for hardware platforms of SBC 5xx0 and SBC 7000.
Local Mode: The licenses are fixed to the SBC and cannot be shared by other devices in the network. Licenses are installed on SBC through EMA or a new CLI interface by applying an xml-based license bundle. The xml-based license adopts the new license format, which includes additional data such as purchase order information.
- Network Mode: The licenses are assigned dynamically by an SLS server based on demand as traffic increases. When the traffic decreases, the licenses are returned to the server. These licenses can float between SBCs based on the demand. Licenses are pooled centrally in the SLS server which is co-located with the EMS.
The system supports a countable license in the range of 0-x units:
- In a local license mode, x is the license units purchased by the user and is part of the xml bundle that is applied directly at the SBC. When the local license mode is zero, it indicates that no license is purchased.
- In a network license mode, x is limited by the number of units available at the Site License Server (SLS), the maximum count configured with the license in the required license table or any basic platform restriction. For example, Call Admission Control (CAC) or media profile configuration.
License Encoded with Fingerprint Capability
- The license is restricted and encoded with the fingerprint capability:
- When the license is generated for a local license deployment, the license is encoded with the fingerprint of the SBC (or SBCs in the case of HA system) and the license is restricted to the SBC that matches the fingerprint.
- When the license is generated for a network license deployment, the license is encoded with the fingerprint of the SLSs (Active and Standby) and the license is restricted to the SLS systems that matches the fingerprint.
License floating enables a limited number of licenses to be shared among a number of network devices It is applicable when the SBC is deployed on network wide licensing with a centralized SLS distributing licenses to the SBCs connected to it.
License Floating Functionality
- The SBC attempts to retrieve a single license from the SLS, when it is configured in the required license table with a minimum count of one (default).
- When the minimum count associated with the license is one, the SBC returns licenses back to the SLS as demanded for the associated license drops. The SBC retains one license from the SLS when the SBC has 0 active call that require the license.
- When the minimum count associated with the license is more than one, the SBC attempts to retrieve the configured number of licenses from the SLS.
- When the minimum count associated with the license cannot be retrieved, but some license count is available, the SBC allows sessions that uses the license (limited by the amount retrieved) and periodically raises a trap to indicate that the SBC is operating below the configured minimum count.
- When the minimum count is updated for the license on a system where the license is already in use, the SBC requests the delta between the minimum license count and the licenses already retrieved from the SLS. If the licenses already retrieved are greater than the configured minimum, then no extra licenses are requested.
- When the minimum count associated with the license is more than one, the SBC retains the configured number of licenses locally even when no sessions require the licenses.
- When the license is configured in the required license table, the maximum license count is set to unlimited by default. The SBC continues to request licenses from the SLS until the underlying platform constraints limit more sessions requiring the license (Example: congestion, configured CAC, media profile.) or the SLS license count associated with the license is reached.
- When a maximum license count of x is configured for the license, the SBC does not retrieve more than x licenses from the SLS.
- When the maximum license count is modified for the license. If the SBC is operating above the newly configured limit, the SBC does not retrieve any more licenses. The new sessions are allowed only after the number of licenses in use drops below the newly configured limit.
- One or more SBCs provisioned with the license in the required license table requests and returns the licenses from the SLS in-line with demand for the license (call-rate that requires MRF transcoding). As the demand increases, the SBC allocates licenses. When the license request is outstanding, and more licenses are available at the SLS, the SBC allows new sessions requiring the license. As call rate drops, unused license counts must be returned to the central pool at the SLS.
There are two ways to delete a license:
From the xml bundle at CLI or EMA for a local license and legacy licenses.
From the Required License Table, in case of network licensing.
The license deletions are allowed:
- Local license bundle containing the license is deleted through EMA/CLI regardless of the current license mode.
- The license name can be removed from the Required License Table regardless of the active mode of licensing configured at the system.
- When license is removed from the required license table, it triggers an appropriate warning to the user along with a prompt, to ask if they wish to continue.
- When the license is removed from the required license table, support for the licensed functionality is disabled system wide.
- When the license is removed from the Required License table, all licenses retrieved to that point are released back to the Site License Server.
Any existing sessions that are initiated prior to the license being removed can continue, but new calls will be denied access to the associated licensed functionality.
- In a local or legacy license mode - Once the license is expired, the SBC treats the licensed functionality as disabled system wide. Any existing sessions that are active on expiry continues unimpaired.
- In a network license mode - Once the license is expired, the SLS does not serve expired licenses to the SBC.
For information related to Alarms/Traps, refer to Alarm Changes.
For CLI configuration, refer to Configuring License Using CLI.