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RFCOMM is the abbreviation for Radio Frequency Communication. The Bluetooth protocol RFCOMM is a simple set of transport protocols, providing emulated RS232 serial ports (up to sixty simultaneous connections of a bluetooth device at a time). RFCOMM is sometimes called Serial Port Emulation. The Bluetooth Serial Port Profile is based on this protocol.   Basically two device types exist that RFCOMM must accommodate.

• Type 1 Devices are communication end points such as computers and printers.
• Type 2 Devices are those that are part of the communication segment; e.g. modems.

Though RFCOMM does not make a distinction between these two device types in the protocol, accommodating both types of devices impacts the RFCOMM protocol.

Bluetooth’s serial port emulation enables the connection of modems (such as in cell phones) and printers. Serial emulation is also an easy way of writing simple data exchange applications using Bluetooth. Object exchange (OBEX)

Facilitated by implementing the OBEX protocol, object exchange is used for “beaming” data objects between devices, such as contacts from address books. It is the main way that cell phones exchange data and is often implemented by Bluetooth-enabled printers.

Bluetooth is just another serial port. And so, Bluetooth communication is actually done via serial connections. You can see for yourself by going to Bluetooth Manager—>Tools—>Settings for All Devices—>Serial Port in your Pocket PC's main menu.