To provide a resilient network infrastructure requires the provision of active hot standby servers to take over in the event of a failure. In such as situation it is desirable that any sessions that were being serviced by the failed server are maintained. This is what stateful failover delivers. All session data that is processed by the primary server is also recorded by the hot standby. If a failover occurs and the hot standby becomes the live server, then the state information is available to continue active sessions from where they were.