Are mobile service providers also ISPs?
Yes. When you use a device like the Treo™ smartphone to access email and the web, your mobile service provider is also an ISP (Internet Service Provider) that uses its digital wireless Wide Area Network to connect you to the Internet. The cellular model is much like the DSL model in that once a smartphone connects to the network it stays logged on, giving the phone instant access to the Internet. In order to use a smartphone on a mobile service network, you need to add a data plan to your mobile service contract.
