Infrared Data Association (IrDA) has defined a group of short-range, high speed, bidirectional wireless infrared protocols, generically referred to as IrDA. IrDA allows a variety of devices to communicate with each other. Cameras, printers, portable computers, desktop computers, and personal digital assistants (PDAs) can communicate with compatible devices using this technology. The IrDA protocol stack is accessed using NDIS connectionless drivers. Figure B.10 illustrates the IrDA protocol architecture.


Figure B.10 IrDA Architecture

The components of IrDA are:

Winsock    Winsock is an API that allows Windows-based applications to access the transport protocols. The IrDA protocol stack is made available to applications by using Winsock.

IrTran-P    IrTran-P is a bidirectional image transfer protocol. Windows 2000 IrTran-P receives data only and is used for cameras with infrared capability. Many cameras have digital ports and can beam infrared data to a receiving computer. That data is then placed in a user-specified (or default) directory.

IrDA Print Monitor    IrDA Print Monitor is a software component that interfaces with an IrDA-connected printer to make that printer appear as any other printer to Windows 2000 users.

IrXfer    IrXfer is an IrDA file transfer application. Files can be dragged and dropped from the desktop to another computer. The Windows 2000 implementation of IrXfer has bidirectional transfer capabilities.

Tiny TP    Tiny TP is a flow control mechanism for IrDA. Tiny TP acts as a regulator to control the rate of data input or output. This prevents an overflow of data from occurring and creating data errors.

IrDA.sys    IrDA.sys is the transport protocol stack that supports IrDA. It provides support for applications through Winsock to the NDIS layer.

IrCOMM    IrCOMM is a software component that supports IrTran-P. IrCOMM uses Winsock, and is interfaced by default to the IrTran-P server. The IrTran-P server must be disabled if other applications need to use the IrCOMM port.

IrLPT    IrLPT is the protocol support that is used by IrDA Print Monitor. IrLPT enables printing directly from IrDA devices to IrDA printers.

IrLMP    Infrared Link Management Protocol is used to multiplex various connections over one IrDA link. Multiplexing is the technique of splitting data from various sources into time slices and sending the data slices in sequence to a destination.

IrLAP    Infrared Link Access Protocol is a media access control software component that determines which component can access the media during each time slice.

FIR Driver    A Fast Infrared driver (FIR) is a miniport driver provided by a hardware vendor to link hardware devices on the lower side of the protocol stack to the transport protocol above, such as TCP/IP or IPX/SPX. FIR devices can exchange data up to 4 megabytes (MB) per second. All FIR devices are also required to support serial transmission using Serial Infrared driver (SIR).

IrSIR.sys    Serial Infrared driver is a Microsoft-provided miniport driver. It is an alternate driver to the Fast Infrared driver and can be used only in combination with Serial.sys. The maximum data transfer rate is 115.2 kilobytes per second (Kbps). In combination with Serial.sys, IrSIR.sys provides support for serial ports.

Serial.sys    Serial.sys is used to connect infrared devices to the IrSIR.sys driver above in the protocol stack and the hardware device below. It is a software driver that sends and receives data from a hardware device and presents it to the IrSIR.sys driver in a format that conforms to the requirements of IrSIR.sys.