Patent ID: 8451828

Claim:
A method for registering an internet protocol (IP) phone linked to a first telephony server and a second telephony server in a dual-link architecture, comprising: pre-registering the IP phone to establish a client link with the first and second telephony servers, comprising: identifying the first telephony server and the second telephony server designated for the IP phone in the dual-link architecture; and sending a registration request to the first and second telephony servers from the IP phone to pre-register the IP phone with the first and second telephony servers; and setting one of the first and second telephony servers as a primary telephony server, comprising: sending an in-service request from the IP phone to one of the first and second telephony servers to identify the primary telephony server for the IP phone and set a remaining server of the first and second telephony servers as a secondary server in a hot standby mode; further comprising conducting a fail-over process for the IP phone from the primary telephony server to a secondary telephony server, comprising: sending an out-service request from the IP phone to the primary telephony server; sending an in-service request from the IP phone to one of the first and second telephony servers that is not the primary telephony server to act as the secondary telephony server; and receiving an in-service acknowledgment from the secondary telephony server at the IP phone.