Highly integrated media access control

• US 8,934,503 B2
• Filed: 06/14/2013
• Issued: 01/13/2015
• Est. Priority Date: 09/27/2001
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Denney, Lisa Voigt, Moshar, Hooman, Horton, John Daniel, Lansing, Shane Patrick, Nazareth, Sean Francis, Pantelias, Niki Roberta
• Primary Examiner(s): MEW, KEVIN D
• Application Number:
  US13/917,972
• Publication Number:
  US 20130279523A1
• Time in Patent Office: 578 Days
• Field of Search: 370/389, 370/392, 370/394, 370/412, 370428-429, 370465-466, 370/469, 370/474, 370/476
• US Class Current: 370/474
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 47/50 Queue scheduling
• CPC Class Codes: H04L 47/52 by attributing bandwidth to queues
• CPC Class Codes: H04L 47/6215 Individual queue per QOS, rate or priority
• CPC Class Codes: H04L 49/9094 Arrangements for simultaneous transmit and receive, e.g. simultaneous reading/writing from/to the storage element
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04N 7/17309 Transmission or handling of upstream communications

Abstract

A supervisory communications device, such as a headend device within a communications network, monitors and controls communications with a plurality of remote communications devices throughout a widely distributed network. The supervisory device allocates bandwidth on the upstream channels by sending MAP messages over its downstream channel. A highly integrated media access controller integrated circuit (MAC IC) operates within the headend to provide lower level processing on signals exchanged with the remote devices. The enhanced functionality of the MAC IC relieves the processing burden on the headend CPU and increases packet throughput. The enhanced functionality includes header suppression and expansion. DES encryption and decryption, fragment reassembly, concatenation, and DMA operations.

Claims

1. A media access controller integrated circuit (MAC IC), comprising:

a pre-processor configured to receive an egress signal from a source node, and to extract payload frames included in the egress signal;

a controller configured to identify a fragmented payload frame from among the extracted payload frames, and to reassemble the fragmented payload frame according to an instruction included in a header of the egress signal; and

a post-processor configured to identify a suppressed packet header included in the extracted payload frames, and to expand the suppressed packet header according to a packet expansion rule.

2. The MAC IC of claim 1, wherein the pre-processor is further configured to prioritize the egress signal based on information included in the egress signal.

3. The MAC IC of claim 2, wherein the information included in the egress signal includes identification information of the source node.

4. The MAC IC of claim 2, wherein the egress signal is stored in a memory associated with the MAC IC according to the prioritization of the egress signal by the pre-processor.

5. The MAC IC Of claim 1, wherein the pre-processor is further configured to check a header checksum (HCS) field or a cyclic redundancy check (CRC) field in the egress signal to perform error correction.

6. The MAC IC of claim 1, wherein the pre-processor is further configured to extract intelligence information from the egress signal in accordance with a security protocol associated with the MAC IC, and to decrypt information included in the egress signal based on the extracted intelligence information.

7. The MAC IC of claim 1, wherein the pre-processor is further configured to determine whether a security protocol field included in the egress signal is enabled, and to process the egress signal based on the determination.

8. The MAC IC of claim 1, wherein the pre-processor is further configured to extract request information included in the egress signal by the source node.

9. The MAC IC of claim 1, wherein the pre-processor is further configured to deconcatenate the extracted payload frames.

10. The MAC IC of claim 1, wherein the post-processor is configured to expand the suppressed packet header that is suppressed according to Data Over Cable Service Interface Specification (DOCSIS) protocol.

11. A method for processing an egress signal in a media access controller integrated circuit (MAC IC), comprising:

receiving, by the MAC IC, the egress signal from a source node;

extracting, by the MAC IC, payload frames included in the egress signal;

identifying, by the MAC IC, a fragmented payload frame from among the extracted payload frames;

reassembling, by the MAC IC, the fragmented payload frame according to an instruction included in a header of the egress signal;

identifying, by the MAC IC, a suppressed packet header included in the extracted payload frames; and

expanding, by the MAC IC, the suppressed packet header according to a packet expansion rule.

12. The method of claim 11, further comprising:

prioritizing the egress signal based on information included in the egress signal.

13. The method of claim 11, wherein the prioritizing includes prioritizing the egress signal based on identification information of the source node.

14. The method of claim 12, further comprising:

storing the egress signal in a memory associated with the MAC IC based on the prioritizing the egress signal.

15. The method of claim 11, further comprising:

performing error correction by checking a header checksum (HCS) field or a cyclic redundancy check (CRC) field in the egress signal.

16. The method of claim 11, further comprising:

extracting intelligence information from the egress signal in accordance with a security protocol associated with the MAC IC, and

decrypting information included in the egress signal based on the extracted intelligence information.

17. The method of claim 16, further comprising:

determining whether a security protocol field included in the egress signal is enabled, and processing the egress signal based on results of the determining.

18. The method of claim 11, wherein the expanding comprises expanding the suppressed packet header that is suppressed according to Data Over Cable Service interface Specification (DOCS S) protocol.

19. A media access controller integrated circuit (MAC IC), comprising:

a pre-processor configured to process an egress signal received from a source node, the pre-processor comprising;

an interface configured to receive the egress signal;

a decryptor configured to extract intelligence information from the egress signal in accordance with a security protocol associated with the MAC IC, and to decrypt information included in the egress signal based on the extracted intelligence information; and

a header processor configured to extract payload frames included in the egress signal;

a controller configured to identify a fragmented payload frame from among the extracted payload frames, and to reassemble the fragmented payload frame according to an instruction included in a header of the egress signal; and

a post-processor configured to identify a suppressed packet header included in the extracted payload frames, and to expand the suppressed packet header according to a packet expansion rule.

20. The MAC IC of claim 19, wherein the decryptor is further configured to determine whether a security protocol field included in the egress signal is enabled, and to process the egress signal based on the determination.