Patent ID: 8700952

Claim:
A transmission control protocol (TCP) high availability (HA) system, comprising: an active processor, having an active application and an active TCP; and a standby processor, having a standby application and a standby TCP, wherein the active processor is directly coupled to the standby processor, and wherein communications and data exchanges among the active application, the active TCP, the standby application, and the standby TCP provide a mechanism for a seamless switch over of an incoming data stream or an outgoing data stream from the active processor to the standby processor, wherein the mechanism includes duplicating a socket associated with an incoming TCP data stream from the active application in the active processor to the standby application in the standby processor, synchronizing a set of data and a set of states corresponding to the socket associated with the incoming TCP data stream between the active TCP and the standby TCP, sending a notification, from the active application, to the active TCP that the standby application in the standby processor is ready to receive data from the socket associated with the incoming TCP data stream, copying a first TCP data received from the socket associated with the incoming TCP data stream, in an input buffer of the active application in the active processor, to the standby application in the standby processor, and sending a sequence number, by the active TCP in the active processor, to the standby TCP in the standby processor, wherein the sequence number corresponds a last byte of the first TCP data delivered through the socket associated the incoming data stream to the active application right before the active TCP receives the notification.