Systems and methods for emergency call route failover

摘要

A system and method for performing an emergency call route failover between an Emergency Call Session Control Function (E-CSCF) and multi-homed remote end-point functions such as Border Gateway Control Function (BGCF)/Media Gateway Control Function (MGCF) or Interconnection Border Control Function (IBCF) in an Internet Protocol Multimedia Subsystem (IMS) uses Session Initiation Protocol (SIP) and/or Domain Name System (DNS) methods. The E-CSCF and/or a DNS server monitors the availability of the remote end-points to create a peer list of route options. The E-CSCF or the DNS server selects a route option from the peer list to route an emergency call to an appropriate Public Safety Answering Point (PSAP). In the event that the route option fails, the E-CSCF fails over to the next available route option to route the emergency call.

主权项

1. A computer-implemented method of performing an emergency call route failover within a telecommunications network, the method comprising:
before receiving a Session Initiation Protocol (SIP) request associated with an emergency call, polling each of multiple gateway nodes at a polling interval; at each polling interval, initiating a SIP OPTION message to each of the multiple gateway nodes; determining a status of each of the multiple gateway nodes based on the initiated SIP OPTION message; and based on the determined status, adding or removing one or more gateway nodes from a list of the multiple gateway nodes,
wherein the list provides one or more routing options for the emergency call; receiving a SIP request associated with the emergency call; selecting a gateway node from the list of one or more routing options; and forwarding a SIP request associated with the emergency call to the selected gateway node to provide the emergency call to an emergency network or emergency network node,
wherein the multiple gateway nodes are Media Gateway Control Function (MGCF) nodes when the emergency network has Time Division Multiplex (TDM) connectivity.