Header compression for CCN messages using dictionary

• US 9,807,205 B2
• Filed: 11/02/2015
• Issued: 10/31/2017
• Est. Priority Date: 11/02/2015
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Mosko, Marc E.
• Primary Examiner(s): Musa, Abdelnabi O
• Application Number:
  US14/930,244
• Publication Number:
  US 20170126851A1
• Time in Patent Office: 729 Days
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

One embodiment provides a system that facilitates efficient packet forwarding. During operation, the system stores, in a storage device in a first node, a static dictionary comprising a mapping between a type and length (TL) string and a compressed replacement string. In response to identifying the TL string in a packet, the system replaces the TL string with the compressed replacement string and transmits the packet to a second node, which stores the static dictionary in a local storage device, thereby facilitating compression of a TL string.

Claims

1. A computer-implemented method for efficient packet forwarding, the method comprising:

storing, in a storage device in a first node, a static dictionary comprising a mapping between a type and length (TL) string and a compressed replacement string;

in response to identifying the TL string in a packet, replacing the TL string with the compressed replacement string, wherein the packet is a content-centric network (CCN) message, and wherein a name for the CCN message is a hierarchically structured variable length identifier (HSVLI) which comprises contiguous name components ordered from a most general level to a most specific level;

replacing a fixed header of the CCN message with a compressed fixed header; and

transmitting the packet to a second node storing the static dictionary in a local storage device, thereby facilitating compression of a TL string.

2. The method of claim 1, wherein the compressed fixed header includes a set of fields representing a format of the compressed fixed header, wherein the set of fields is one of:

a first set of fields comprising a pattern identifying the format, a version, a packet type, a packet length, and a hop limit;

a second set of fields comprising a pattern identifying the format, a version, a packet type, a header length, and a packet length; and

a third set of fields comprising a pattern identifying the format, a version, a packet type, a header length, a packet length, and a hop limit.

3. The method of claim 2, wherein the field lengths of the fixed header and the compressed fixed header are the same, and wherein the pattern in the third set of fields indicate that the header of the CCN message has been compressed.

4. The method of claim 1, wherein the TL string includes contiguous TL pairs without an intermediate value.

5. The method of claim 1, wherein the compressed replacement string includes a length field indicating a variable length associated with the TL string.

6. The method of claim 1, further comprising adding a compression header to the packet, wherein the static dictionary is one of a plurality of static dictionaries, wherein the compression header includes a context identifier that identifies the static dictionary from the plurality of static dictionaries.

7. A computer system for facilitating forwarding of packets, the system comprising:

a processor; and

a storage device storing instructions that when executed by the processor cause the processor to perform a method, the method comprising;

storing, in a storage device in a first node, a static dictionary comprising a mapping between a type and length (TL) string and a compressed replacement string;

in response to identifying the TL string in a packet, replace the TL string with the compressed replacement string, wherein the packet is a content-centric network (CCN) message, and wherein a name for the CCN message is a hierarchically structured variable length identifier (HSVLI) which comprises contiguous name components ordered from a most general level to a most specific level;

replacing a fixed header of the CCN message with a compressed fixed header; and

transmitting the CCN message to a second node storing the static dictionary in a local storage device, thereby facilitating compression of a TL string.

8. The computer system of claim 7, wherein the compressed fixed header includes a set of fields representing a format of the compressed fixed header, wherein the set of fields is one of:

a first set of fields comprising a pattern identifying the format, a version, a packet type, a packet length, and a hop limit;

a second set of fields comprising a pattern identifying the format, a version, a packet type, a header length, and a packet length; and

a third set of fields comprising a pattern identifying the format, a version, a packet type, a header length, a packet length, and a hop limit.

9. The computer system of claim 8, wherein the field lengths of the fixed header and the compressed fixed header are the same, and wherein the pattern in the third set of fields indicate that the header of the CCN message has been compressed.

10. The computer system of claim 7, wherein the TL string includes contiguous TL pairs without an intermediate value.

11. The computer system of claim 7, wherein the compressed replacement string includes a length field indicating a variable length associated with the TL string.

12. The computer system of claim 7, wherein the method further comprises adding a compression header to the packet, wherein the static dictionary is one of a plurality of static dictionaries, wherein the compression header includes a context identifier that identifies the static dictionary from the plurality of static dictionaries.

13. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method, the method comprising:

storing, in a storage device in a first node, a static dictionary comprising a mapping between a type and length (TL) string and a compressed replacement string;

in response to identifying the TL string in a packet, replace the TL string with the compressed replacement string, wherein the packet is a content-centric network (CCN) message, and wherein a name for the CCN message is a hierarchically structured variable length identifier (HSVLI) which comprises contiguous name components ordered from a most general level to a most specific level;

replacing a fixed header of the CCN message with a compressed fixed header; and

transmitting the packet to a second node storing the static dictionary in a local storage device, thereby facilitating compression of a TL string.

14. The storage medium of claim 13, wherein the compressed fixed header includes a set of fields representing a format of the compressed fixed header, wherein the set of fields is one of:

a first set of fields comprising a pattern identifying the format, a version, a packet type, a packet length, and a hop limit;

a second set of fields comprising a pattern identifying the format, a version, a packet type, a header length, and a packet length; and

a third set of fields comprising a pattern identifying the format, a version, a packet type, a header length, a packet length, and a hop limit.

15. The storage medium of claim 13, wherein the TL string includes contiguous TL pairs without an intermediate value.

16. The storage medium of claim 13, wherein the compressed replacement string includes a length field indicating a variable length associated with the TL string.

17. The storage medium of claim 13, wherein the method further comprises adding a compression header to the packet, wherein the static dictionary is one of a plurality of static dictionaries, and wherein the context identifier identifies the static dictionary from the plurality of static dictionaries.