Cable modem system and method for dynamically mixing protocol specific header suppression techniques

• US 6,963,931 B2
• Filed: 10/11/2001
• Issued: 11/08/2005
• Est. Priority Date: 10/11/2000
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Bunn, Fred A., Johnson, Thomas L.
• Primary Examiner(s): Etienne, Ario
• Assistant Examiner(s): Duong, Oanh L.
• Application Number:
  US09/973,781
• Publication Number:
  US 20020062394A1
• Time in Patent Office: 1,489 Days
• Field of Search: 709246-247, 375/222, 375/257, 370/393, 370/474
• US Class Current: 709/246
• CPC Class Codes: H03M 7/30 Compression speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
• CPC Class Codes: H03M 7/3088 employing the use of a dictionary, e.g. LZ78
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/765 intermediate
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04N 21/437 Interfacing the upstream path of the transmission network, e.g. for transmitting client requests to a VOD server flow control in data networks H04L47/10; streaming protocols, e.g. RTP or RTCP, H04L65/65; scheduling or organising the servicing of application requests in data packet switching networks H04L67/60
• CPC Class Codes: H04N 21/4622 Retrieving content or additional data from different sources, e.g. from a broadcast channel and the Internet web site content organization and management for information retrieval from the Internet G06F16/958; transmission by internet of broadcast information H04H60/82; stock exchange data over packet-switching network H04L12/1804; push services including data channel over packet-switching network H04L12/1859
• CPC Class Codes: H04N 21/4782 Web browsing , e.g. WebTV
• CPC Class Codes: H04N 21/6332 directed to client
• CPC Class Codes: H04N 21/6402 Address allocation for clients address allocation in data networks H04L61/50
• CPC Class Codes: H04N 21/64322 IP
• CPC Class Codes: H04N 21/6437 : Real-time Transport Protocol [RTP]
• CPC Class Codes: H04N 7/17336 : Handling of requests in head-ends
• CPC Class Codes: H04W 28/06 : Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365

Abstract

A cable modem system and method is provided for the transfer and processing of data in accordance with specialized data transfer protocols while utilizing conventional cable modem termination system (CMTS) equipment. A cable modem system in accordance with the invention includes a cable modem that provides for the modification of data packets in accordance with one or more proprietary protocols and the addressing of the modified data packets to a CMTS. The CMTS is adapted to reconstruct the data packets.

Claims

1. A method for dynamically mixing header suppression techniques for transmitting data over a Data Over Cable Service Interface Specification (DOCSIS) network, comprising the steps of:

(a) communicating a plurality of header suppression techniques and a unique index number assigned to each of the plurality of header suppression techniques to a cable modem termination system;

(b) receiving a plurality of data packets to be transmitted;

(c) identifying which of the received data packets have a header that should be suppressed;

(d) selecting a header suppression technique from the plurality of header suppression techniques for each of the identified data packets;

(e) appending a packet header element to each of the identified data packets, the packet header element containing the index number assigned to the header suppression technique selected for each of the identified data packets; and

(f) suppressing a header of each of the identified data packets using the header suppression technique selected for each of the identified data packets; and

(g) concatenating each data packet within a single DOCSIS transmit burst to form a mixed protocol burst, the mixed protocol burst comprising a plurality of data packets having headers suppressed in accordance with a corresponding plurality of header suppression techniques.

2. The method of claim 1, further comprising the step of:

(h) transmitting the mixed protocol burst to the cable modem termination system.

3. The method of claim 1, wherein each of the received data packets that are unknown Internet Protocol (IP) packets are identified as having a header that should be suppressed in said identifying step (c).

4. The method of claim 3, wherein DOCSIS payload header suppression is selected in said selecting step (d) for each of the received data packets that are unknown IP packets.

5. The method of claim 1, wherein each of the received data packets that are Internet Protocol (IP)/Real-Time Transfer Protocol (RTP) packets with dynamically changing patterns are identified as having a header that should be suppressed in said identifying step (c).

6. The method of claim 5 wherein RTP suppression is selected in said selecting step (d) for each of the received data packets that are IP/RTP packets with dynamically changing patterns.

7. The method of claim 1, wherein each of the received data packets that are Internet Protocol (IF)/Transmission Control Protocol (TCP) variable length packets are identified as having a header that should be suppressed in said identifying step (c).

8. The method of claim 7, wherein dynamic delta encoding suppression is selected in said selecting step (d) for each of the received data packets that are IP/TCP variable length packets.

9. A method for expanding data packet headers transmitted over a Data Over Cable Service Interface Specification (DOCSIS) network, comprising the steps of:

(a) receiving a mixed protocol burst comprising a plurality of data packets having headers suppressed in accordance with a corresponding plurality of header suppression techniques, the data packets being concatenated within a single DOCSIS transmit burst;

(b) identifying each data packet within the mixed protocol burst that has a suppressed header;

(c) searching a lookup table to select a set of rules from a plurality of sets of rules for expanding a suppressed header of each of the data packets identified in step (b); and

(d) expanding a suppressed header of each of the data packets identified in step (b) according to a set of rules selected in step (c).

10. The method of claim 9, wherein each data packet identified in said identifying step (b) has an appended packet header element containing an index number.

11. The method of claim 10, wherein said searching step (c) uses each index number contained in each appended packet header element to search the lookup table.

12. The method of claim 11, wherein DOCSIS payload header expansion rules are used in said expanding step (d) for unknown Internet Protocol (IP) packets.

13. The method of claim 11 wherein Real-Time Transfer Protocol (RTP) expansion rules are used in said expanding step (d) for Internet Protocol (IP)/RTP packets with dynamically changing patterns.

14. The method of claim 11, wherein dynamic delta encoding expansion rules are used in said expanding step (d) for Internet Protocol (IP)/Transmission Control Protocol (TCP) variable length packets.

15. A system for dynamically mixing header suppression techniques transmitted over a Data Over Cable Service Interface Specification (DOCSIS) network, comprising:

one or more cable modems that suppress data packet headers by selectively using one of a plurality of header suppression techniques wherein said one or more cable modems concatenates each data packet having a suppressed header into a single DOCSIS transmit burst to form a mixed protocol burst, the mixed protocol burst comprising a plurality of data packets having headers suppressed in accordance with a corresponding plurality of header suppression techniques; and

a cable modem termination system (CMTS) enabled to expand said data packet headers by using a set of expansion rules corresponding to said selected one of said plurality of header suppression techniques, wherein said one or more cable modems assigns a unique index number to each one of said plurality of header suppression techniques.

16. The system of claim 15, wherein said one or more cable modems appends a packet header element to each data packet having a suppressed header, wherein said packet header element includes said unique index number assigned to the header suppression technique used to suppress each data packet header.