Describes the wireless AAA authentication survivability cache feature.
The Wireless AAA authentication survivability cache feature enhances the reliability of wireless client authentication by storing successful authentication results locally on the controller. This cache includes details such as the client's MAC address, user name, hashed password, and Attribute-Value Pairs (AVPs) received from the RADIUS server.
Wireless AAA authentication survivability cache is a mechanism implemented in the controller that:
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provides a fallback methodology in wireless systems for AAA authentication servers,
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implements authentication and policy caching mechanism, and
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leverages the caching capability of the AAA module of System Management Daemon (SMD) in WNCd.
This feature is supported in both local mode and FlexConnect central authentication mode.
Wireless AAA authentication survivability cache as failover mechanism
If the AAA server becomes unreachable, for example, due to a network outage or server failure, the controller uses the cached credentials to authenticate clients. This ensures that the previously authenticated clients are allowed network access, even if the primary authentication source is unavailable.
Use case for wireless AAA authentication survivability cache
Some use cases for the wireless AAA authentication survivability cache feature are:
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Cache can be used when the controller loses connectivity with the AAA server, which may disconnect authenticated clients.
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Cache can be used as the primary source of authentication, with fallback to AAA, to avoid slow authentication time due to WAN latency.
Benefits of using AAA cache for failover
The benefits of using AAA cache for failover are:
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Seamless client access: If the AAA server fails, previously authenticated clients can still access the network without delays or disruptions.
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Reduced dependency on AAA server availability: This mechanism reduces the dependency on the availability of the AAA server for re-authentication, providing business continuity even if there is an issue with the server.
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Improved user experience: Clients do not experience interruptions when reconnecting, as the controller uses the cached authentication information to grant them access immediately.
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Load reduction on AAA server: During network failures or outages, the controller does not need to query the AAA server repeatedly for authentication. This helps reduce the load on the AAA server.
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Failover for high availability: If the primary AAA server temporarily fails, such as during maintenance, the AAA cache maintains client access automatically.