Transporting serially over TCP/IP using raw TCP encapsulation

Patent metadata

Field	Value
Publication number	US-9294584-B2
Application number	US-201313921619-A
Country	US
Kind code	B2
Filing date	Jun 19, 2013
Priority date	Jun 19, 2013
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

In one embodiment, a router establishes a serial-over-TCP/IP (Transmission Control Protocol/Internet Protocol) communication session between terminal units using raw-TCP encapsulation. For the session, the router maps serial characters to TCP out-of-band (OOB) communication fields, maps serial flow control signals to TCP/IP receiver-window advertisements, and dynamically adjusts a TCP/IP priority based on serial payload priority. Accordingly, the router may thus communicate data over the serial-over-TCP/IP session based on the mappings and priority.

First claim

What is claimed is:

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.

Assignees

• Cisco Tech Inc

Inventors

• Mahamuni Atul B
• Barrett Carol

Classifications

• H04L69/324

  in the data link layer [OSI layer 2], e.g. HDLC · CPC title

• H04L69/163

  In-band adaptation of TCP data exchange; In-band control procedures · CPC title

• H04L47/35

  by embedding flow control information in regular packets, e.g. piggybacking · CPC title

• H04L67/60

  Scheduling or organising the servicing of application requests, e.g. requests for application data transmissions using the analysis and optimisation of the required network resources (admission control or resource allocation H04L47/70) · CPC title

• H04L69/22 Primary

  Parsing or analysis of headers · CPC title