Patent attributes
A mechanism provides for communication of “keep-alive” messages from clients to servers in a packet telephony network environment. The servers may be call agents and the clients may be gateways or MGCP-controlled IP phones. A client (e.g., gateway) registers a virtual endpoint. Upon a period of inactivity in which the client does not receive any commands or acknowledgments from an assigned server (e.g., call agent), the client starts to send keep-alive messages periodically to the server. The keep-alive message may include an endpoint identifier that identifies the registered virtual endpoint. If the server fails to respond to the keep-alive messages after a period of time, the client initiates a fallback mechanism from a first call control protocol (e.g., MGCP) to a second call control protocol (e.g., H.323 or SIP), to provide call control handling using a default application. The keep-alive messages may be sent to other servers among the plural servers that are configured to operate with the client before determining whether to initiate the fallback mechanism. During the fallback state, the keep-alive message may be sent periodically until a response is received from the server. Communications with the assigned server may be reestablished thereupon based on the first call control protocol.
