Ericsson today landed its first U.S. mobile softswitch deployment, announcing a deal for its IP switching infrastructure and future Wi-Fi/cellular convergence trials with southeastern operator SunCom Wireless.

Ericsson has installed its call server/mobile switching center architecture in SunCom's domestic five-state footprint, covering the Carolinas and parts of Tennessee, Georgia and Virginia. The carrier, however, will not use the solution in its networks in Puerto Rico and the U.S. Virgin Islands. The switch went into operation in September after two months of installation, SunCom officials said. The switch now handles about 20% of SunCom's GSM voice traffic, and it is scheduled to take over voice traffic in 2006, said Scott Basham, vice president of engineering for SunCom.

The carrier has also agreed to conduct an IP Multimedia Subsystem (IMS) architecture trial with Ericsson using the new switch and other network elements to launch blended voice and data services over an integrated IP network. The first application up for trial will be Ericsson's Unlicensed Mobile Access solution, which allows voice calls, messaging services and data connections to pass between the wide area cellular network and local area wireless networks such as Wi-Fi hot spots or Bluetooth.

Ericsson's Mobile Softswitch Solution is actually not a true softswitch, but a hybrid switch designed to transition legacy circuit switched networks to IP. Called an R4 switch (based on the 3rd Generation Partnership Project's release 4 standard), the hybrid technology is going into almost all GSM networks, but Ericsson has had little success in deploying the architecture in the U.S. until now. Competitor Alcatel has landed R4 deals with each of the two major GSM providers, T-Mobile and Cingular. Alcatel is upgrading the former AT&T Wireless of "blue" networks with the technology and handling UMTS voice traffic through a subcontracting deal with Siemens.

SunCom has 920,000 customers in its five-state footprint, Puerto Rico and the Virgin Islands.