Retrofit TDI Stack Filter which intercepts Callback Commands and replaces them with Receive Commands allowing packet delays and traffic shaping

摘要

Some computer network communications stacks use the Transport Dispatch Interface (TDI) protocol. This protocol provides two methods for moving data from the Transport Provider (TP) to the TDI Client (TC). The first (Fig. 1) is Callback whereby the TC gives the TP blanket permission to send any data it receives. The second (Fig. 1) is the Receive Command whereby the TP is given permission to send specific data, and must then wait for a further receive command before sending more. Some stacks do not provide the receive command functionality. This invention adds a TDI Filter between the TC and the TP, which intercepts the Callback registration sent by the TC. It then sends Receive Commands to the TP. The Receive Command can be used for introducing delays into the passing of data up the stack, and thereby can permit bandwidth shaping. Using the TDI Filter avoids the need to alter the existing programs.