Choosing a Wireless Provider for your Application

by James Werwath

Most WAP (Wireless Application Protocol) developers will agree that developing a wireless application with WML (Wireless Markup Language) or HDML (Handheld Device Markup Language) markup is not a full solution. A wireless application needs to use the radio network to deliver this content to a phone. In the Chicago area, AT&T wireless and SprintPCS offer the path of least resistance for wireless developers by offering certification programs and developer support. This is a competitive space, however, and the likes of Cingular Wireless, Verizon, and NextTel are already offering opportunities to use their service for wireless applications. This article points out several questions that developers might consider when choosing a wireless service or recommending a wireless service for their clients.

Note: the word "Customer" refers to the owner of a wireless application and "User" refers to the user of this application.

(1) What is your coverage area for wireless service ? - Customers' coverage needs will be different and may not be immediately obvious. For example, if a customer's headquarters is in San Jose, California, you might want to consider a service that covers, or plans to cover that city. Even if the application is being used elsewhere, folks at HQ might want to try it out. Wireless applications for mobile workforces often require coverage of major highways. In this case, a good question to ask a customer is "How do you expect your drivers' routes to change over the next couple years?" Also be aware that just because one gets voice service, one is not guaranteed wireless internet service. My AT&T phone, for example, gets wireless internet service in Chicago, but in Milwaukee, I am "roaming" on another network and I cannot use the wireless internet service, even though I can make and receive voice calls.

2) What WAP gateway do you use ? - AT&T, SpintPCS, and to the author's knowledge, every other US WAP provider, use phone.com UP.Link server. As of this writing, both AT&T and SprintPCS are using version 3.2.x with plans to upgrade to 4.x, but with no set date. This version of the gateway allows dynamic WML to HDML conversions for phones that only support HDML. Therefore, developers can develop using WML and not worry about phones supporting only HDML. Neither AT&T nor SprintPCS allow customers to host their own gateways.

3) What is your policy on Alerts ? - Alerts are unsolicited messages "pushed" to a phone. Wireless application developers recognize this as a powerful tool not available in conventional browsers. Phone.com's UP.Link 3.x supports both secure and unsecure alerts. At the time of this writing, both AT&T and SprintPCS allow unsecure alerts to a phone. This means you do not need a certificate for authentication. You will need to know the hostname of the alerts server. AT&T is currently hosted at pn.mobile.att.net SprintPCS is up2.upl.sprintpcs.com. In WAP 1.2, proprietary "Alerts" are replaced by standard WAP Push Protocol. I would assume that when phone.com supports WAP 1.2 Push Protocol, their products will continue to support the proprietary UP.Link 3.x Alert format. Make certain that the push protocols used by an application are supported by the provider's gateway.

4) Assuming Alerts are supported, does the phone need to be in data mode to receive them ? - The advantage of Alerts is immediate notification. In the AT&T network however, a dual mode phone can only receive alerts when it is in Data mode. If it is in voice mode, the Alert will be received only when the customer reconnects to the Data network (assuming the alert's time-to-live has not timed out). SprintPCS does not have this problem.

5) Is some sort of messaging via email available ? - Some customers may require a more standard interface for real time notifications. For this reason, messaging to the phone via email is a nice alternative to Alerts. Both SprintPCS and AT&T wireless offer an email interface to their messaging systems. For example, if a users phone number is 1112223333, they can receive messages via 111222333@mobile.att.net on the AT&T network, 1112223333@messaging.sprintpcs.com on the SprintPCS network.

6) Do you have a developer program ? If so, what does it entail ? - AT&T and SprintPCS both have developer programs. Both have documentation resources, message boards, and tech support. With AT&T, AT&T wireless personnel post on the AT&T message boards, contributing valuable inside information. For a fee, one can even get certified as an "AT&T Certified Wireless Developer". The URLs for these programs are listed at the end of the article.

7) What is the best resource for technical support ? - Unfortunately, this is not a question one is likely to get answered easily. It took the author many phone calls and emails to many people at both AT&T and SprintPCS to locate a person that could address technical issues. If you are interested in avoiding this search, you may contact the author. In any case, it doesn't hurt to ask. The good news is that both AT&T and SprintPCS have expressed great interest in working with wireless application developers and content providers.

8) Can a user access any URL or are they limited to approved content providers ? - When the user is able to browse any wireless site, the content provider doesn't have to endure a partnership process in order to be accessible on that provider's network. At the time of this writing, SprintPCS allows one to browse any HDML or WML site. AT&T however, charges an additional fee to browse any URL. A good follow up question to this one is "Do you allow users to store bookmarks for any URL?" This helps so the user does not have to type the URL for the Customer's application each time they want to use it. With SprintPCS, this is included with the basic fee. With AT&T you will pay extra.

9) How are customers billed for wireless service ? - Customers want to know how much they will be spending. At SprintPCS, "Wireless Web Services are billed by the usage time, the same as voice services, or by number of messages/updates in the case of Wireless Web Messaging " AT&T is the same except they charge additional monthly fees for additional services. Details are available at http://www.attws.com/personal/explore/pocketnet/data_plans.html

10) How long does it take to establish a wireless internet connection ? - AT&T uses circuit switched data on their TDMA (Time Division Multiple Access) network. What this means to the user is that they must establish a connection to begin wireless service. With AT&T, one can wait 30 seconds or more for a wireless internet connection. Customers should be made aware of this limitation. SprintPCS uses a CDMA (Code Division Multiple Access) network but also uses circuit switched data. Even though both networks use circuit switched data, the SprintPCS connection time is much less, at least in the Chicago area.

11) What phones are available and what browser are they running ? - Wireless developers will need to know things like "All phones for provider X are running UP.Browser 3.1 and therefore DO NOT support WMLScript". Currently, both AT&T phones and SprintPCS phones are running the UP.Browser 3.1. Be aware that some customers may have preferences for specific phone manufactures.

12) Can you change your home deck ? - Customers may wish that their own wireless homepage come up first when a user of the application connects to the service. Customers that purchase a wireless application may not want their users to buy books or trade stocks while on the clock. Currently, AT&T does not allow customized home decks. Neither does SprintPCS. This would be a very attractive feature.

13) What about Palm ? - Many customers are excited about wireless applications on the Palm. (Especially those who have ever had to type a 3 paragraph email on a phone.) AT&T has a CDPD network for Palm applications. At this time, SprintPCS does not.

14) What are your plans for the future ? - As wireless developers, we do our best to look ahead and see what our customers may require in the future. Location Based Services, iMode (a.k.a. cHTML - a subset of HTML suitable for wireless devices), and VoiceXML are all hot topics in wireless news today. If we identify a customer need for such a technology, we want to be sure our provider has a plan for supporting it.

In summary, even the greatest WML application is of little use without wireless service. As wireless developers, we must ask many questions to ensure our customers' current and future needs will be met. The following URLs can help:

About The Author: James Werwath is an AT&T Certified Wireless Developer, Sun Certified Java Programmer and Architect currently developing wireless solutions at Novarra Inc.. He can be reached at jwerwath@novarra.com.