Method and apparatus for providing circuit switched domain services over a packet switched network

摘要

A method of determining a domain mode for a mobile station operating in either a circuit-switched domain or a packet-switched domain. A first domain mode is determined, and then a determination is made whether to rove from the first domain mode to a second domain mode. The determination may be made by a Packet Mobile Switching Center (PMSC) when, for example, the mobile station moves between Routing Areas. Alternatively, the mobile station may make the determination based, for example, on pre-provisioned selection criteria. The mobile station derives a Fully Qualified Domain Name (FQDN) based on a cell identifier of a current cell and uses the FQDN in a DNS query to obtain the IP address of the PMSC.