Opportunistic transmission control protocol (TCP) connection establishment

1. A method, comprising:

receiving, at a Transmission Control Protocol (TCP) intermediate device, a first SYN packet from a TCP client that is a first initial message to establish a first TCP connection between the TCP client and a TCP origin server, wherein the TCP intermediate device splits the first TCP connection between the TCP client and the TCP origin server into a second TCP connection between the TCP client and the TCP intermediate device and a third TCP connection between the TCP intermediate device and the TCP origin server;

prior to the second TCP connection being fully established, transmitting, by the TCP intermediated device, a second SYN packet to the TCP origin server, wherein the second SYN packet is a second initial message to establish the third TCP connection between the TCP intermediate device and the TCP origin server;

transmitting a first SYN-ACK packet to the TCP client as part of establishing the second TCP connection;

receiving a first ACK packet from the TCP client as part of establishing the second TCP connection, wherein the second TCP connection is established responsive to processing the first ACK packet;

receiving, a second SYN-ACK packet from the TCP origin server as part of establishing the third TCP connection; and

transmitting a second ACK packet to the TCP origin server as part of establishing the third TCP connection.

2. The method of claim 1 , wherein transmitting the second SYN packet occurs prior to transmitting the first SYN-ACK packet to the TCP client.

3. The method of claim 1 , wherein transmitting the second SYN packet occurs after transmitting the first SYN-ACK packet to the TCP client and prior to receiving the first ACK packet from the TCP client.

4. The method of claim 1 , further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that the first SYN packet is addressed to the TCP origin server.

5. The method of claim 1 , further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that the first SYN packet is received on a trusted interface or authenticated IP tunnel.

6. The method of claim 1 , further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that a number of TCP connection initiations received from the TCP client where a TCP connection is not established does not exceed a threshold.

7. The method of claim 1 , further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that a number of TCP connection initiations to the TCP origin server where a TCP connection is not established does not exceed a threshold.

8. A non-transitory machine-readable storage medium that provides instructions that, if executed by a processor, will cause said processor to perform operations including:

receiving, at a Transmission Control Protocol (TCP) intermediate device, a first SYN packet from a TCP client that is a first initial message to establish a first TCP connection between the TCP client and a TCP origin server, wherein the TCP intermediate device splits the first TCP connection between the TCP client and the TCP origin server into a second TCP connection between the TCP client and the TCP intermediate device and a third TCP connection between the TCP intermediate device and the TCP origin server;

prior to the second TCP connection being fully established, transmitting, by the TCP intermediate device, a second SYN packet to the TCP origin server, wherein the second SYN packet is a second initial message to establish the third TCP connection between the TCP intermediate device and the TCP origin server;

transmitting a first SYN-ACK packet to the TCP client as part of establishing the second TCP connection;

receiving a first ACK packet from the TCP client as part of establishing the second TCP connection, wherein the second TCP connection is established responsive to processing the first ACK packet;

receiving, a second SYN-ACK packet from the TCP origin server as part of establishing the third TCP connection; and

transmitting a second ACK packet to the TCP origin server as part of establishing the third TCP connection.

9. The non-transitory machine-readable storage medium of claim 8 , wherein transmitting the second SYN packet occurs prior to transmitting the first SYN-ACK packet to the TCP client.

10. The non-transitory machine-readable storage medium of claim 8 , wherein transmitting the second SYN packet occurs after transmitting the first SYN-ACK packet to the TCP client and prior to receiving the first ACK packet from the TCP client.

11. The non-transitory machine-readable storage medium of claim 8 , the operations further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that the first SYN packet is addressed to the TCP origin server.

12. The non-transitory machine-readable storage medium of claim 8 , the operations further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that the first SYN packet is received on a trusted interface or authenticated IP tunnel.

13. The non-transitory machine-readable storage medium of claim 8 , the operations further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that a number of TCP connection initiations received from the TCP client where a TCP connection is not established does not exceed a threshold.

14. The non-transitory machine-readable storage medium of claim 8 , the operations further comprising:

prior to transmitting the second SYN packet to the TCP origin server, determining that a number of TCP connection initiations to the TCP origin server where a TCP connection is not established does not exceed a threshold.

15. An apparatus, comprising:

a processor; and

a non-transitory machine-readable storage medium that provides instructions that, if executed by the processor, will cause the processor to carry out operations including:

receive, at a Transmission Control Protocol (TCP) intermediate device, a first SYN packet from a TCP client that is a first initial message to establish a first TCP connection between the TCP client and a TCP origin server, wherein the TCP intermediate device is to split the first TCP connection between the TCP client and the TCP origin server into a second TCP connection between the TCP client and the TCP intermediate device and a third TCP connection between the TCP intermediate device and the TCP origin server;

prior to the second TCP connection being fully established, transmit a second SYN packet to the TCP origin server, wherein the second SYN packet is a second initial message to establish the third TCP connection between the TCP intermediate device and the TCP origin server;

transmit a first SYN-ACK packet to the TCP client as part of establishing the second TCP connection;

receive a first ACK packet from the TCP client as part of establishing the second TCP connection, wherein the second TCP connection is to be established responsive to processing the first ACK packet;

receive, a second SYN-ACK packet from the TCP origin server as part of establishment of the third TCP connection; and

transmit a second ACK packet to the TCP origin server as part of establishment of the third TCP connection.

16. The apparatus of claim 15 , wherein transmission of the second SYN packet is to occur prior to transmission of the first SYN-ACK packet to the TCP client.

17. The apparatus of claim 15 , wherein transmission of the second SYN packet is to occur after transmission of the first SYN-ACK packet to the TCP client and prior to receipt of the first ACK packet from the TCP client.

18. The apparatus of claim 15 , the operations further including:

prior to transmission of the second SYN packet to the TCP origin server, determine that the first SYN packet is addressed to the TCP origin server.

19. The apparatus of claim 15 , the operations further including:

prior to transmission of the second SYN packet to the TCP origin server, determine that the first SYN packet is received on a trusted interface or authenticated IP tunnel.

20. The apparatus of claim 15 , the operations further including:

prior to transmission of the second SYN packet to the TCP origin server, determine that a number of TCP connection initiations received from the TCP client where a TCP connection is not established does not exceed a threshold.

21. The apparatus of claim 15 , the operations further including:

prior to transmission of the second SYN packet to the TCP origin server, determine that a number of TCP connection initiations to the TCP origin server where a TCP connection is not established does not exceed a threshold.