The HTTP 1.1 standard is being used as part of communication to a server. The client fails to maintain the session within the maximum timeout defined by the server. Which device is responsible for end

The load balancer applies its own idle timeouts independently; it does not directly enforce the server-defined HTTP session timeout on behalf of the server.

The server defines the timeout and initiates the teardown signal, but in a routed topology where BIG-IP is the default gateway, the actual session termination is handled by the gateway device.

In many F5 BIG-IP deployments, the load balancer is the default gateway for backend servers. When the server's HTTP 1.1 keep-alive timeout expires because the client failed to send a request in time, the server initiates teardown traffic that flows through the BIG-IP as its default gateway - making the BIG-IP the device that ultimately processes and completes the session teardown in this topology.

The client failed to maintain the session within the timeout, meaning the client did not act; the responsibility for ending the session falls on the network device in the return path.