Patent ID: 8199648

Claim:
A method comprising: at a packet sender device, adding a flow control identifier to a packet, the flow control identifier being based on: storing an estimated buffer depth for a packet receiver device; and determining if the stored estimated buffer depth has reached a minimum; adding a flow control instruction to the packet to instruct the packet receiver device to enter a “no transmit” state; sending the packet with the flow control identifier and the flow control instruction to the packet receiver device over a data path; receiving, from the packet receiver device, flow control data that includes a received flow control identifier generated in response to the sent flow control identifier, the received flow control identifier identifying a state of the receiver buffer in response to receiving the last packet sent by the packet sender device; comparing the sent flow control identifier with the received flow control identifier to determine when flow control data between the packet sender device and the packet receiver device is synchronized; and modifying a transmission flow control instruction based on the comparison.