Analyzing and selecting a mobile data service can be a daunting task. This tip provides a checklist of the major factors to consider when evaluating mobile data services (GSM, CDMA and WiMAX).
Alphabet soup
Do you ever wonder whether mobile operators deliberately try to make their technology sound confusing? After all, why would anyone name a technology EV-DO (Evolution-Data Optimized) or HSDPA (High Speed Downlink Packet Access)? At least mobile WiMAX (Worldwide Interoperability for Microwave Access) sounds like Wi-Fi -- but, alas, mobile WiMAX service is not yet available. And if the names weren't confusing enough, the technology continues to evolve with new, equally arcane names such as EV-DO Rev A and High Speed Uplink Packet Access (HSUPA).
All in the family
Mobile data services have evolved from narrowband voice service "afterthoughts" to mainstream broadband services. Although there are many mobile wireless technologies, there are just two major technology families deployed in the U.S. today -- with a third technology on the way (see Figure 1).
Figure 1: Mobile data services
- GSM Family: Approximately 2.5 billion subscribers worldwide use the Global System for Mobile Communications (GSM) family of technologies. AT&T (previously Cingular Wireless) and T-Mobile are the major GSM operators in the U.S.
- CDMA Family: More than 500 million subscribers worldwide use the Code Division Multiple Access (CDMA) family. Verizon Wireless and Sprint are the major CDMA operators in the U.S.
- WiMAX: The Mobile WiMAX service is not yet available in the U.S. but will soon be offered by Sprint and Clearwire. The technology is based on the IEEE 802.16e standard and promises greater throughput and range than CDMA and GSM.
Making sense of it all
Analyzing and selecting a mobile data service can be a daunting task. A complete analysis requires a thorough evaluation of many service characteristics, and it is easy to lose the forest for the trees. Therefore, when evaluating mobile data services, be sure to stay focused on the following major considerations:
International travel: Do your users travel internationally? If so, consider selecting a GSM-based service. A mobile phone that operates on a GSM network in the U.S. will also work on the many other GSM networks around the world.
Length of contract: The mobile operators have penetrated over 75% of the U.S. wireless market. As penetration rates approach 100%, service providers will become hyper-competitive, resulting in a buyer's market. Therefore, try to keep your contracts as short as possible because prices will probably fall.
Coverage: All of the major providers offer coverage maps. But those maps do not provide sufficient detail to ensure adequate coverage. Check the coverage yourself by asking field personnel, business associates and friends about their experience with the mobile service.
Throughput: Downlink speeds (from the network to the phone) are reaching well over 500 kbps, but uplink speeds are still slow. EV-DO Rev A and HSUPA will improve uplink speeds to several hundred kbps. One way to get a sense of the real-world performance is to perform a small-scale pilot before making a major deployment decision. Be sure to collect information in different regions, at different times of the day, and on different days during the week.
Latency: Mobile services based upon EV-DO Rev 0 and HSDPA (or older technologies) can have network latency well over 400 milliseconds. If you are planning to run latency-sensitive applications such as voice, be sure to use the newer EV-DO Rev A and HSUPA (note that the combination of HSDPA and HSUPA is sometimes referred to as HSPA).
Conclusion
Mobile data services now provide high-speed data connections throughout many regions in the U.S., but analyzing these various services and technologies can be confusing and time consuming. If you stay focused on a few "big picture" considerations, you will be able to navigate through the many service options and select the one that is best for you.
About the author: Paul DeBeasi is a Senior Analyst at the Burton Group and has over 25 years experience in the networking industry. Before joining the Burton Group, Paul founded ClearChoice Advisors, a wireless consulting firm, and was the VP Product Marketing at Legra Systems, a wireless-switch innovator. Prior to Legra, Paul was the VP Product Marketing at startups IPHighway and ONEX Communications and was also the Frame Relay product line manager for Cascade Communications. Paul began his career developing networking systems as a senior engineer at Bell Laboratories, Prime Computer, and Chipcom Corporation. Paul holds a BS degree in Systems Engineering from Boston University and a Master of Engineering degree in Electrical Engineering from Cornell University.
Paul is a well-known conference speaker and has spoken at many events including Interop, Next Generation Networks, WiFi Planet, Internet Telephony and more.
