2. Voice Vs. Data

Voice services are widely used by both individual and corporate subscribers. Data services are most heavily used by businesses for uploading and downloading files; marketing and sales database access; e-mail, GPS services and text and instant messaging.

Voice is a standard service for all of the carriers. It is what most of them started with. It is about as easy as pulling teeth on a kicking mule to get a wireless phone without voice services. So, voice services should be the most reliable, because they have been around longer, right? Well, yes and no. Typically, quality of service depends on the radio frequencies used to transmit calls and on the number of towers. Sometimes a whole frequency can be a problem. Signs of frequency problems include irregularly dropped calls, sporadic audio problems and even periods when audio moves in only one direction. Of course some of these problems can be attributed to coverage suddenly disappearing when you are moving around. I must emphasize that these sorts of problems occur irregularly. If problems occur regularly, it's more likely attributable to high numbers of voice calls or a need to reset the phone. Again, if you regularly call from some place on the fringe of a coverage area, unlikely in more urban areas, you could experience these problems.

Some carriers activate data services separately from voice services. Often this is done at the same time voice is activated. I have known the activation of voice services to fail if data services are not activated at the same time. If your wireless device has been activated for voice and data, you can usually deactivate data with no charge. If your device is data-only, such as a PCMCIA- or PCI-based wide area network adapter for your notebook computer, deactivating data might involve not only a charge for deactivation, but, if you have a contract that has not expired, a penalty charge for deactivating data services.

Voice and data require different provisioning, relating a code in the device with voice or data service. Most importantly, the code is used in the authentication process I discussed earlier. Voice is provisioned based on your SIM card number. How data services are provisioned depends on the carrier. When I was working with Nextel-Sprint, Nextel based provisioning on an IP address, which made troubleshooting a breeze for the most part. Sprint, on the other hand, used an NAI (Network Analysis Infrastructure) code to provision data. NAI's can be a pain to deal with because there are about 10 extra steps involved in the provisioning process and almost that many to fix it if it isn't working. In my experience the biggest problem with data services is reliability. Voice and data fight each other for bandwidth, with each trying to limit the other. Granted, the two services work OK for a lot of subscribers, but I can't tell you how many times re-provisioning of one or the other was required when I was working with customers.