Techniques are described in which a network device waits differing amounts of time for different network sockets before beginning processes to determine whether respective network connections from the network sockets have failed. An intermediate device may create a network socket for a network connection having a keep-alive wait time option set to a keep-alive wait time associated with a class of the network connection. If an amount of time specified by the keep-alive option of the socket passes after a last successful communication on the network connection, the socket may begin a process to determine whether the network connection has failed. If the intermediate device determines that the network connection has failed, the intermediate device may terminate the connection to free resources on the intermediate device allocated to the network connection.