Data-flow architecture for a TCP offload engine

An integrated circuit (IC), comprising:

• an Ethernet controller;
• an internet protocol (IP) controller, coupled to the Ethernet controller;
• and
• a transmission control protocol (TCP) offload engine, coupled to the IP controller, the TCP offload engine including:
• a receive circuit having a receive data path and a receive control interface, the receive data path coupled to store received TCP data for a plurality of TCP sessions in a respective plurality of receive buffers in an external memory circuit external to the IC;
• a transmit circuit having a transmit data path and a transmit control interface, the transmit data path coupled to read TCP data to be transmitted for the plurality of TCP sessions from a respective plurality of transmit buffers in the external memory circuit;
• a receive application interface coupled between the receive buffers in the external memory and an application circuit;
• a transmit application interface coupled between the application circuit and the transmit buffers in the external memory;
• and
• a control circuit coupled to the receive control interface and the transmit control interface and decoupled from the receive data path and the transmit data path, the control circuit configured to maintain data structures to maintain TCP state information for the plurality of TCP sessions.

A method of operating a transmission control protocol (TCP) offload engine in an integrated circuit (IC), the method comprising:

• storing TCP data received from an application circuit through a receive application interface on a receive data path for a plurality of TCP sessions in a respective plurality of receive buffers in an external memory circuit external to the IC;
• transmitting TCP data to be transmitted from the application circuit through a transmit application interface on a transmit data path for the plurality of TCP sessions from a respectively plurality of transmit buffers in the external memory circuit;
• and
• maintaining data structures to maintain TCP state information for the plurality of TCP sessions in a control circuit that is decoupled from the receive data path and the transmit data path.