A method and apparatus for transmitting commands between a TCP stack and an offload unit and for communicating receive and transmit data buffer locations is described. A command ring buffer stored in system memory is used to transmit commands from the TCP stack to the offload unit and to transmit command status from the offload unit to the TCP stack. A notification ring buffer is used to transmit connection information from the offload unit to the TCP stack. Other ring buffers are used to transmit locations of transmit buffers or receive buffers stored in system memory from the TCP stack to the offload unit.