* Multiple unified voice-delivery mechanisms compete
A tug of war rages over the optimum way to deliver mobile voice applications.
By “voice applications,” I’m talking about VoIP calls integrated with associated telephony-centric applications (presence, messaging, chat) that workers can use without interruption whether they are in their own offices or out on the public mobile WAN somewhere.
The industry is attacking the challenge of “seamless” voice delivery from several angles:
* From the mobile network operator perspective. This school of thought says that since most of the voice handsets deployed today are cellular handsets, it makes sense to keep those handsets in place and beef up the cellular coverage within enterprise walls with distributed antenna systems and cellular repeaters. This scenario de-emphasizes voice over Wi-Fi and bets on 3G VoIP as the dominant delivery mechanism.
* From the enterprise CPE perspective. The reasoning here is that since most enterprises already run a PBX, have business phones, and, increasingly, are running wireless LANs, it makes sense to take the business phone and mobilize it with a business phone number that can reach users wherever they are. This approach requires dual-mode cellular/Wi-Fi phones, a voice-optimized Wi-Fi network, and enterprise-class equipment for handling internetwork signal handoff for roaming.
* A mix of the above. Prominent IP PBX makers are joining forces with dual-mode cellular-Wi-Fi handset makers to extend their PBX applications to these hybrid devices. For example, at the recent 3GSM conference in Barcelona, Cisco and Nokia announced dual-mode 802.11g/GSM smart phones that can run on Cisco’s CallManager IP PBX-based VoIP network and on GSM cellular networks.
While there is yet no seamless roaming between networks, the Nokia E61i and E65 smart phones reportedly contain software enabling the devices to sense and select the strongest network signal for highest-quality conversations.
And in Japan, NTT DoCoMo subscribers reportedly can roam between mobile WAN and Wi-Fi networks with DoCoMo’s N902iL dual-mode Wi-Fi/FOMA handset (FOMA is Japan’s version of 3G) while using Cisco CallManager features and application software. This is more or less a carrier-delivery approach to extending the rich PBX capabilities and applications of the enterprise.
More on these approaches next time.
