Siemens stretched the impression of vendor consensus on push-to-talk to its limits with the launch of its first phone based on IMS (IP Multimedia Subsystem).
Conspicuous by its absence in Siemens’ release of the CX70 phone was any mention of Push to Talk Over Cellular (PoC). Instead, the CX70 was hailed as the first “Push and Talk” phone, operating over the IMS.
“We don’t want any proprietary solutions and also employ open standards for Push and Talk,” Lothar Pauly, member of the Board of Siemens’ mobile communication division, explained. “Only with complete interoperability will we be able to develop the promising potential of this new service to the full.”
IMS switching technology enables IP-based connections between mobile phones and is based on the specifications of the Third Generation Partnership Project (3GPP). IMS will be the control layer for many multimedia services, such as video transmission, instant messaging and virtual reality application like multiparty gaming.
For network operators, Push and Talk over IMS, which can already be implemented into GPRS networks, represents another step towards 3G. Siemens’ Push and Talk server would be integrated into the IMS network structure and linked to existing infrastructure components.
From Siemens’ description, it is difficult to see much difference between Push and Talk and PoC. First, the user selects the people he or she wants to talk to from a list. At the push of a button, all of these previously defined addressees receive an invitation which they can accept or decline. As soon as the calling partners have confirmed, the initial caller pushes the PaT button and starts the conversation, which everyone hears simultaneously. The “Always On” feature of the GPRS network maintains the connection all along.
Siemens plans to incorporate Push and Talk capability in all its mid-range phones, Lothar Pauly said.
“We will steadily expand this new market segment and play a leading role in its development,” he claimed.
“Starting next year, all mid-range Siemens mobile phones will be Push and Talk capable.”
All devices for the PaT service will provide access to IMS core networks and be equipped with an open-standard PaT client. Siemens Mobile thus hopes to guarantee its phones’ interoperability with the infrastructure of other manufacturers.
Industry analyst Northstream provided a positive voice for the future of the technology, “Push and Talk has the potential to increase the traffic over mobile networks. The mobile voice chat supplements SMS and eliminates the cumbersome setup of conference calls. This mobile service will soon be able to replace the traditional radio communications of freight forwarders, courier services, taxi companies or building contractors. For private users, Push and Talk has a chance of becoming the latest trend. It is conceivable, for example, that network operators will offer open PaT forums. Push and Talk is a new service for the mass market.”
As, presumably, does Push to Talk.