Kodiak Networks today released a bevy of new advanced voice services for its push-to-talk Real-Time Exchange (RTX) platform, offering up VoIP-like enhanced features for deployment over the circuit-switched network.

Kodiak introduced presence controls, instant voice conferencing, push voice messaging and call upgrading, which allows users to turn push-to-talk calls into duplex voice calls on the fly. Kodiak also added roaming capabilities, new handset-based contact and group management functionality and basic text alert capabilities to the RTX feature stack, as well as CALEA support.

The new features are all software upgrades to Kodiak's existing RTX, allowing carriers to deploy them over their existing push-to-talk service with only a software upgrade to the handset. On the GSM side, Kodiak has developed a SIM card-based upgrade solution using Sun Microsystems' Java Card technology. Carriers can simply ship new SIM cards to their users. The SIM cards in turn upgrade the client software in their phones as well as store the contacts and settings for the service so users can transfer the service from one phone to another.

Push-to-talk services were popularized by Nextel in the last decade, but the mass deployment of the services has been rather slow. The industry has sought a standard for the application, known as push-to-talk over cellular, which uses VoIP over packet networks. But according to Kodiak vice president of business development Bruce Lawler, the standards process has been slow and the networks capable of supporting an IP-based version of push-to-talk are still years away. Since then, many carriers have turned to proprietary solutions like Kodiak's to get to the market sooner. With data still accounting for only a fraction of carriers' revenue, and standard voice minutes all but commoditized, carriers are looking for a way to capitalize on new voice features, even if it means sacrificing network interoperability, Lawler said.

"Push-to-talk over cellular is a good standard, and when the standard is formed we'll support it," Lawler said. "But you just can't deploy push-to-talk over a GPRS network. You can only deploy over a UMTS network."

Until those UMTS networks are widely available, carriers will look toward solutions that work on the standard voice circuit, Lawler said. Kodiak's solution, however, is IP in the core and has IP Multimedia Subsystem interfaces, allowing it to launch these IP services before the arrival of end-to-end IP. "We've developed these services ahead of schedule," Lawler said. "We were driven by market demand."