A Virtual Soft-Hand-off method for wireless IP-centric CDMA networks whose routers, hosts, and mobile stations have small group multicast (SGM) capability comprises setting up an explicit synchronous multicast session among a small group of participants with dynamic group membership. Packets transmitted over the multicast session are time stamped to help maintain synchronization, and the receivers recover multiple packet flows from the multiple received signals concurrently and combine them to create a single packet flow at higher layers.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a non-provisional application of provisional application Ser. No. 60/278,014 filed Mar. 22, 2001.
A mobile terminal having a packet communication function according to a mobile IP and a communication route optimizing function includes a session controller for setting a session between terminals in accordance with a session control message of a protocol different from the mobile IP. When a session control message from the other party is received in a visited mobile IP network, the session controller executes optimization of a communication route to the other party by the communication route optimizing function before transmitting a response for the received message.
Within a mobile communications device, a method of roaming between a mobile network and a wireless network can include establishing a Voice-Over Internet Protocol communications link with an endpoint over which a call is conducted, wherein at least a portion of the call is conducted over the wireless network. The method further can include initiating a handoff of at least a portion of the call from the wireless network to the mobile network using a Session Initiation Protocol refer method and continuing the call using the mobile network for at least a portion of the call rather than the wireless network.