When Sprint recently announced that it would deploy Mobile WiMAX over the next two years in what it called a migration to 4G, it applied some pressure on other U.S. mobile carriers to either join the race or explain why they aren't ready to do so. The pressure might seem especially acute for Cingular Wireless, which has the largest customer base in the U.S. market but is widely perceived as the least aggressive among the top three mobile carriers in deploying 3G. Telephony Editor-in-Chief Dan O'Shea recently spoke to Cingular's Chief Technology Officer Kris Rinne on a wide range of topics, including the need for 4G, the ongoing expansion of 3G, the emergence of IP multimedia subsystem, the trend of vendor consolidation and the lack of female technology executives in the telecom industry.

On the need for 4G: We need to be sure we don't become too fragmented. We're just now building out the 3G ecosystems, and we need to continue to grow 3G technologies and gain experience with the content going over these networks, as opposed to leaping into another technology generation with no business case for it. As an industry, we need to evolve 3G for faster throughput and lower latency. We need to focus on working with 3G to support growth in mobile content services.

HSDPA has been around for several years through the development of the technology and the testing and deployment, and it really does take that amount of time to create the necessary economies of scale and do all of the tests that we need to do. Every carrier will take their own position on Mobile WiMAX, but our focus should be on the customer rather than on the technology war. You have to create the right applications for the enterprise environment or the consumer. That gets us back to the importance of taking the time to build the ecosystem that can make that happen. With a new technology, you need to rebuild that ecosystem.

On the interest Cingular's parent firms have in Mobile WiMAX: Our parent companies have been focused on Fixed and nomadic WiMAX solutions and not really for mobility. [Editor's note: Cingular owners AT&T and BellSouth both have conducted WiMAX trials, and BellSouth offers pre-WiMAX fixed wireless in several markets.] For us, what they're doing with those technologies is complementary to what we're doing with HSDPA. With Mobile WiMAX, what really concerns me is that it offers us no backward-compatibility with what we're doing now.

On Cingular's ongoing 3G network expansion: We've got HSDPA in 22 cities, and we're continuing to expand, with a hand-off in those markets to our existing UMTS coverage. The focus then becomes getting the right services and support tools. We're well down the path of understanding consumer behavior. We have 20 million data customers. We're continuing with our plan of record — to introduce UMTS in most of our major markets and then HSDPA. A lot of that will be in urban markets where we can follow our existing EDGE traffic usage trends. Our goal is to have HSDPA everywhere we have UMTS. We continuously look at and assess where to improve our technology. We won't expand on our network capability just because of what Sprint is doing. HSDPA can accomplish a lot and has a pretty good speed evolution all within the same 5 MHz to 10 MHz of spectrum.

Today, our HSDPA capability is about 1.8 Mb/s [theoretical peak]. We'll move to 3.6 Mb/s later this year, and next year, we'll go to 7.2 Mb/s and also to higher speeds in the uplink portion. So in the life of this 3G technology, there is a lot of evolution and value we can continually add. At the same time, we focus on more than bandwidth. We focus on clicks to content and latency, too.

On the 3GPP's Long-Term Evolution standard for mobile broadband: We do monitor and participate in the LTE discussion, and that will be a standard based on OFDM [orthogonal frequency division multiplexing — also the basis for Mobile WiMAX]. That is down the road somewhere, but as I said, there are a lot of things we can do to continue improving the technology that we have, and that's a position we're very comfortable with right now.

On Verizon Wireless' Advances to IMS initiative: We're still in our early review of that proposal, but I think there are some things in A-IMS that are already being addressed. There is a sub-group within the 3GPP standards architecture that has addressed the need for support of non-SIP solutions, and in fact, we have some of that working in our labs already. Cingular has been very bullish on IMS in terms of its potential to offer multiple bearers in a converged voice environment. But it's important to remember that it's a subsystem, not a complete and total system.

We have been very active in 3GPP during the adoption of Release 5 and Release 7 of the IMS standard, and there are some issues I would have loved to see move faster. The voice call continuity specification to allow that voice convergence is one thing, but I think that's now moving at an appropriate pace, and the industry is gathering its rationale for supporting that kind of service.

On the growing trend of vendor consolidation: Because we use a technology in GSM that is used around the globe, we have a lot of choices for vendors. We have a lot of flexibility to mix and match vendors. I think vendor consolidation makes sense. It really strengthens the research capability that a company can put into a particular technology. The way we choose vendors is the way we always have: We go through an RFP process, and once we have made a choice, we talk to them about our view of the next 24 months or so, and we talk about their view and we reach an agreement. We're always make sure we're meeting up with other vendors and keeping up with what they are doing.

On the lack of female technology executives in the industry: I have 30 years of experience in this industry, having started out in wireline, and I've always found it a very open-minded industry. I've never felt like there were places a women couldn't get to — though sometimes it was hard to find the washroom. There are other women in high-level technology positions at other companies, but the industry as a whole needs to continue to foster diversity. There is a challenge all the way into the high school and elementary education levels to encourage girls in math and science areas early on. That will provide a broader, more diverse base for recruiting.