Transporting serially over TCP/IP using raw TCP encapsulation

1. A method, comprising:

establishing a serial-over-TCP/IP (Transmission Control Protocol/Internet Protocol) communication session between terminal units using raw-TCP encapsulation;

mapping serial characters to TCP out-of-band (OOB) communication fields;

mapping serial flow control signals to TCP/IP receiver-window advertisements;

dynamically adjusting a TCP/IP priority based on serial payload priority; and

communicating data over the serial-over-TCP/IP session based on the mapped serial characters, the mapped serial flow control signals and the adjusted TCP/IP priority.

2. The method as in claim 1 , wherein the serial characters comprise instructions that are to be processed prior to any pending data already received by a receiver.

3. The method as in claim 1 , wherein the serial characters comprise a serial break signal.

4. The method as in claim 1 , wherein the TCP OOB communication fields comprise an urgent flag and urgent pointer.

5. The method as in claim 1 , wherein the serial flow control signals comprise request to send/clear to send (RTS/CTS) signals.

6. The method as in claim 1 , wherein the serial flow control signals comprise XON and XOFF signals.

7. The method as in claim 1 , wherein a high serial payload priority for which a high TCP/IP priority is set corresponds to an unsolicited response as the serial payload.

8. The method as in claim 1 , wherein the TCP/IP priority is set within one of either a type-of-service (ToS) field or a Differentiated Services Code Point (DSCP) field.

9. An apparatus, comprising:

a serial data link network interface configured to communicate over a serial data link with a local terminal unit;

an Internet Protocol (IP) network interface configured to communicate over an IP session with a remote router;

a processor coupled to the network interfaces and adapted to execute one or more processes; and

a memory configured to store a process executable by the processor, the process when executed operable to:

establish a serial-over-TCP/IP (Transmission Control Protocol/Internet Protocol) communication session between terminal units using raw-TCP encapsulation;

map serial characters to TCP out-of-band (OOB) communication fields;

map serial flow control signals to TCP/IP receiver-window advertisements;

dynamically adjust a TCP/IP priority based on serial payload priority; and

communicate data over the serial-over-TCP/IP session based on the mapped serial characters, the mapped serial flow control signals and the adjusted TCP/IP priority.

10. The apparatus as in claim 9 , wherein the serial characters comprise instructions that are to be processed prior to any pending data already received by a receiver.

11. The apparatus as in claim 9 , wherein the serial characters comprise a serial break signal.

12. The apparatus as in claim 9 , wherein the TCP OOB communication fields comprise an urgent flag and urgent pointer.

13. The apparatus as in claim 9 , wherein the serial flow control signals comprise request to send/clear to send (RTS/CTS) signals.

14. The apparatus as in claim 9 , wherein the serial flow control signals comprise XON and XOFF signals.

15. The apparatus as in claim 9 , wherein a high serial payload priority for which a high TCP/IP priority is set corresponds to an unsolicited response as the serial payload.

16. The apparatus as in claim 9 , wherein the TCP/IP priority is set within one of either a type-of-service (ToS) field or a Differentiated Services Code Point (DSCP) field.

17. A tangible, non-transitory, computer-readable media having software encoded thereon, the software when executed by a processor operable to:

establish a serial-over-TCP/IP (Transmission Control Protocol/Internet Protocol) communication session between terminal units using raw-TCP encapsulation;

map serial characters to TCP out-of-band (OOB) communication fields;

map serial flow control signals to TCP/IP receiver-window advertisements;

dynamically adjust a TCP/IP priority based on serial payload priority; and

communicate data over the serial-over-TCP/IP session based on the mapped serial characters, the mapped serial flow control signals and the adjusted TCP/IP priority.

18. The computer-readable media as in claim 17 , wherein the serial characters comprise a serial break signal.

19. The computer-readable media as in claim 17 , wherein the TCP OOB communication fields comprise an urgent flag and urgent pointer.

20. The computer-readable media as in claim 17 , wherein the serial flow control signals are selected from a group consisting of: request to send/clear to send (RTS/CTS) signals; and XON and XOFF signals.