On top of having to understand threading, HTTP, and XML you must now also be aware of network details about how data will be sent and then choose the right transport for the application. Each transport has strengths and weaknesses such that there is no single right way to send data over the network. Additionally, as a developer, you have to determine which transports are available and then choose which one is the best choice to use for sending data.
There are six types of transports that are available on a BlackBerry. Each of them can be specified through one or more connection string directives and all can be used to carry HTTP data.
Any transport can be used to send data, but each one has its own set of concerns and restrictions. The default connection type depends on how your device is configured, but generally, the default is a good place to start. However, you should also understand each connection type as well.