What is Mobile VoIP?

by Mark Hewitt

From my "Ask the Expert" monthly column

Mobile VoIP is defined as an extension of mobility to a VoIP network (as described in Wikipedia). Thus, it is a method of expanding the utility of VoIP in our everyday lives and not just a technology.

At the CTIA (Cellular Telephony Industry Association) show in Las Vegas recently, I saw several innovative approaches designed to tackle the power problem with WiFi and WiMax devices – Broadcom, for example, introduced a system-on-a-chip that reduced the power requirements by 50%. This is the single most critical obstacle to the deployment of direct mobile handsets with “Always On” connections required to support a direct SIP client.

It is this “Always On” nature of a future Mobile VoIP product that we are beginning to see in hybrid Cellular phones, and for any of you playing with them it becomes quite clear that battery life cannot keep up with a pure SIP client mobile solution.

We have yet another major issue in North America with the capacity of Internet Bandwidth falling behind the world quickly, while our costs are not declining as rapidly as in many foreign markets. I note in Jim Baller’s April 10th broadband newsletter that Japan’s price per Mbps for its highest bandwidth offerings ($0.13/Mbps) is considerably lower than the US ($2.83/Mbps), and that the average download speed in Japan is now 93.7 Mbps, while the US is more than 10 times slower at 8.9 Mbps.

It is for this reason that current practical implementation of a Mobile VoIP solution must remain a “bridge” to broadband networks and operate over existing Cellular infrastructure and in a cooperative fashion with the incumbent providers.

Look out for the WiMax 802.16m standard to settle the score between networks and devices. I predict the convergence of 3G technology and WiFi to mature into a 4G standard offering 100 Mbps (mobile) and 1 Gbps (fixed) coverage by 2010. I can only hope that this timetable helps explain the “gap” we face until both technology and business models adapt to a very rapidly changing environment. Mobile VoIP is just the beginning – soon expect the “V” in VoIP to also mean Video.