Apparatus and method for full-duplex ethernet communications

• US 5,504,738 A
• Filed: 04/15/1994
• Issued: 04/02/1996
• Est. Priority Date: 10/27/1992
• Status: Expired due to Term

• Current Assignee: LSI Corporation (Broadcom, Inc.)
• Original Assignee: Seeq Technology, Inc. (Broadcom, Inc.)
• Inventors: Sambamurthy, Namakkal S., Lai, Woo-Ping, VanGilder, John P.
• Primary Examiner(s): Safourek, Benedict V.
• Application Number:
  US08/227,851
• Time in Patent Office: 718 Days
• Field of Search: 370/24, 370/26, 370/31, 370/85.3, 375/212, 375/219, 375/220, 375/377, 371/32, 371/57.2, 178/4.1 C, 178/692, 178/69 H
• US Class Current: 370/296
• CPC Class Codes: H04L 12/40013 Details regarding a bus controller
• CPC Class Codes: H04L 12/40136 Nodes adapting their rate to the physical link properties LAN switches H04L49/351
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/44 Star or tree networks
• CPC Class Codes: Y10S 370/91 Carrier sense multiple access, e.g. ethernet, 10base-t

Abstract

A downward compatible full-duplex 10Base-T ethernet transceiver associated with both the hub or the remote node in an ethernet network includes generator circuitry for generating a full-duplex-capability signal indicating its full-duplex capability for transmission over the twisted pair link and detector circuitry for detecting transmission of such a signal from the transceiver with which it is communicating across the twisted pair link. The detector circuitry responds to the full-duplex-capability signal by sending a full-duplex enable signal to an ethernet controller configured according to the present invention. An ethernet controller contains circuitry responsive to the full-duplex-enable signal to disable transmission deferral in response to a carrier-sense signal generated by the transceiver. The full-duplex-capability indicator portion may comprise an extra pulse following an Nth link-integrity pulse after a delay of between about 2-7 μsec.

Claims

1. A method of implementing communication between a first node coupled to an ethernet transceiver and a second node coupled to said ethernet transceiver, said method comprising

transmitting, from said first node, a link-integrity signal having a capability-indicator portion indicating a communication capability available at said first node, said capability-indicator portion being downward compatible with a half-duplex 10Base-T capability of said ethernet transceiver;

receiving said link-integrity signal at said second node;

detecting said capability-indicator portion of said link-integrity signal at said second node; and

transmitting, from said second node, a capability signal responsive to said capability-indicator portion of said link-integrity signal.

2. A method as in claim 1, wherein said capability-indicator portion comprises an indicator of a protocol capability of said first node.

3. A method as in claim 2, wherein said protocol capability comprises capability for a full-duplex communication protocol.

4. A method as in claim 2, comprising

comparing, at said second node, a capability indicated by said capability-indicator portion with a capability available at said second node;

and

communicating between said first node and said second node using a set of capabilities available at both said first node and said second node.

5. A method of establishing communication on a network, said method comprising

transmitting a link-integrity signal, said link-integrity signal being downward compatible with a half-duplex 10Base-T capability of an ethernet transceiver, from a first node on said network, said link-integrity signal comprising an indicator of a type of communication capability;

receiving said link-integrity signal at a second node on said network;

transmitting a capability signal from said second node, responsive to said indicator.

6. A method as in claim 5, wherein said indicator and said capability signal each comprises an indicator of a protocol capability.

7. A method as in claim 6, wherein said protocol capability comprises capability for a full-duplex communication protocol.

8. A method as in claim 6, comprising

comparing, at said second node, a capability indicated by said capability-indicator portion with a capability available at said second node;

and

communicating between said first node and said second node using a set of capabilities available at both said first node and said second node.

9. A method as in claim 5, wherein said indicator comprises an indicator of a plurality of protocol capabilities.

10. A method as in claim 9, wherein said plurality protocol capabilities comprise an indicator of a full-duplex capability and an indicator of a 10Base-T capability.

11. A method as in claim 9, comprising

comparing, at said second node, a capability indicated by said capability-indicator portion with a capability available at said second node;

and

communicating between said first node and said second node using a set of capabilities available at both said first node and said second node.

12. A method of establishing communication on a network, said method comprising

transmitting a link-integrity signal from a first node on said network, said link-integrity signal comprising a first plurality of pulses and a second plurality of pulses interspersed with said first plurality of pulses, said second plurality of pulses comprising a set of data bits;

receiving said link-integrity signal at a second node on said network, said second node being coupled to an ethernet transceiver, said first plurality of pulses comprising a link-integrity signal recognizable by said ethernet transceiver;

detecting said second plurality of pulses at said second node; and

transmitting, from said second node, a link-integrity signal responsive to said second plurality of pulses of said first link-integrity signal.

13. A method as a claim 12, wherein said second plurality of pulses of said first link-integrity signal comprises at least one bit representative of a protocol capability of said first node.

14. A method as in claim 13, wherein said protocol capability comprises capability for a full-duplex communication protocol.

15. A method as in claim 13, comprising

comparing, at said second node, a capability indicated by said at least one bit with a capability available at said second node;

and

communicating between said first node and said second node using a set of capabilities available at both said first node and said second node.

16. A communication network, comprising

a communication medium;

a first and a second node;

an ethernet transceiver coupled to said second node; and

a link-integrity signal comprising

a first plurality of pulses, whereby said first plurality of pulses comprise a link-integrity signal recognizable by said ethernet transceiver;

a second plurality of pulses interspersed with said first plurality of pulses, said second plurality of pulses comprising a set of data bits representative of a communication capability of said first node.

17. A network as in claim 16, wherein said first plurality of pulses comprise a sequence of pulses having a substantially uniform temporal spacing and defining a sequence of interpulse gaps.

18. A network as in claim 16, wherein said second plurality of pulses are disposed in at least some of said interpulse gaps.