Method and apparatus for automatic configuration of a network connection

• US 5,577,023 A
• Filed: 08/06/1993
• Issued: 11/19/1996
• Est. Priority Date: 12/01/1992
• Status: Expired due to Fees

• Current Assignee: Farallon Computing Incorporated
• Original Assignee: Farallon Computing Incorporated
• Inventors: Webber, Harold H., Marum, John
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Patel, Ajit
• Application Number:
  US08/103,395
• Time in Patent Office: 1,201 Days
• Field of Search: 370/16, 370/16.1, 370/14, 370/85.3, 370/85.2, 370/13, 370/54, 370/93, 370/94.3, 370/31, 371/180, 371/181, 371/189.01, 371/189.02, 340/825.01, 340/827, 455/8, 455/79, 178/71 R, 375/219, 375/220
• US Class Current: 370/225
• CPC Class Codes: H04L 12/44 Star or tree networks
• CPC Class Codes: H04L 12/46 Interconnection of networks

Abstract

The present invention provides automatic configuration of the transmit and receive paths of a network connection, preferably a 10Base-T network connection. It senses which pair in a cable is used for TX signals and which is used for RX signals, then it automatically swaps or unswaps the RX and TX pairs of the port so that a connection is made regardless of whether a crossover or straight-through cable is used. The invention uses link integrity pulses, which are used to periodically test the integrity of the network, to determine which pair is for reception and which is for transmission. Since the auto-crossover transceiver has line receivers and line drivers connected to both pairs of the cable, once it determines which pair is TX and which is RX, it selects the appropriate line receiver and driver to match the cable configuration. The present invention allows connection to a network where another node on the network is either of the standard "hub" type, of the standard "MAU" type, or of the auto-crossover type.

Claims

1. Connecting means for connecting a first device to signal lines in a network, wherein said signal lines comprise a first signal line and a second signal line, said connecting means comprising:

first selecting means coupled to said signal lines for alternately selecting said second signal line and said first signal line as a receive path;

sensing means coupled to said first selecting means and to said first device for sensing link integrity pulses on said first signal line from a second device coupled to said signal lines in said network;

second selecting means coupled to said signal lines for alternately selecting said first signal line and said second signal line as a transmit path, said first signal line being selected as a transmit path when said second signal line is selected as a receive path and said second signal line being selected as a transmit path when said first signal line is selected as a receive path;

generating means coupled to said second selecting means and to said first device for generating link integrity pulses on said transmit path for transmission to said second device.

2. The connecting means of claim 1 further comprising:

first control means for controlling said first selecting means;

second control means for controlling said second selecting means.

3. The connecting means of claim 2 further comprising:

receiving means coupled to said first selecting means for receiving receive data over said first signal line;

transmitting means coupled to said second selecting means for transmitting transmit data over said second signal line;

interface means for interfacing said receiving means and said transmitting means to said first device.

4. The connecting means of claim 3 further comprising:

bypass means coupled to said signal lines for bypassing said first device and for ensuring continuity of said network when said connecting means is in an unpowered state.

5. The connecting means of claim 3 wherein said network comprises a 10Base-T network.

6. Apparatus comprising:

a first unidirectional communication path;

a second unidirectional communication path;

selecting means selectably coupled to said first unidirectional communication path and to said second unidirectional communication path for monitoring said first unidirectional communication path and said second unidirectional communication path for a received network status signal from a remote node and for selecting a receive path among said first unidirectional communication path and said second unidirectional communication path and a transmit path among said first unidirectional communication path and said second unidirectional communication path in response to said received network status signal.

7. The apparatus of claim 6 further comprising:

generating means for generating network status signals;

transmitting means for transmitting said network status signals to said remote node over said transmit path;

control means for controlling said generating means and for controlling said selecting means to periodically alternate between, during a first period of time, selecting said first unidirectional communication path as a receive path and said second unidirectional communication path as a transmit path and, during a second period of time, selecting said first unidirectional communication path as a transmit path and said second unidirectional communication path as a receive path.

8. The apparatus of claim 7 wherein said apparatus is for connecting to a 10Base-T network.

9. A method of configuring a network connection comprising the steps of:

transmitting a first transmitted network status signal over a first unidirectional communication path, said first transmitted network status signal for signalling a node;

monitoring a second unidirectional communication path for a received network status signal;

transmitting a second transmitted network status signal over said second unidirectional communication path, said second transmitted network status signal for signalling said node;

monitoring said first unidirectional communication path for said received network status signal;

transmitting a third transmitted network status signal over said second unidirectional communication path after receiving said received network status signal over said first unidirectional communication path, said third transmitted network signal indicating successful negotiation of directional orientation of said first unidirectional communication path and said second unidirectional communication path.

10. The method of claim 9 further comprising the steps of:

testing whether a timeout delay has been exceeded to determine which of said steps to perform next;

testing whether a link good state has been entered to determine whether successful network communication may occur.

11. The method of claim 10 further comprising the step of:

ignoring a receiver input for a period of time.

12. Apparatus comprising:

automatic selection means coupled to a first unidirectional path and a second unidirectional path, said automatic selection means for automatically identifying a directional orientation of said first unidirectional path and said second unidirectional path and for selecting said first unidirectional path for transmission and said second unidirectional path for reception in response to a signal received from a node on said second unidirectional path.

13. The apparatus of claim 12 wherein said apparatus is coupled to a Base-T network.

14. Apparatus comprising:

a first twisted pair communication line;

a second twisted pair communication line;

a first network node coupled to said first and second twisted pair communication lines; and

a second network node coupled to said first and second twisted pair communication lines, said second network node comprising;

selecting means for alternately selecting said first twisted pair communication line as a transmit path and said second twisted pair communication line as a receive path during a first mode and said first twisted pair communication line as a receive path and said second twisted pair communication line as a transmit path during a second mode;

link integrity pulse generating means coupled to said selecting means for generating link integrity pulses and for transmitting said link integrity pulses over said transmit path to said first network node;

sensing means coupled to said selecting means for sensing incoming link integrity pulses from said first network node on said receive path and for stopping selecting means from alternating between said first and second modes after said incoming link integrity pulses are sensed on said receive path;

transmitting means coupled to said selecting means for transmitting data to said first network node over said transmit path; and

receiving means coupled to said selecting means for receiving data from said first network node over said receive path.

15. Apparatus comprising:

a network;

a first communication path coupled to said network;

a second communication path coupled to said network;

a device;

a third communication path coupled to said device;

a fourth communication path coupled to said device;

selecting means selectably coupled to said first communication path, said second communication path, said third communication path, and said fourth communication path for monitoring said first communication path and said second communication path for a received network status signal received from said network and for coupling said first communication path to said third communication path and said second communication path to said fourth communication path when a network status signal is received by said selecting means from said network over said second communication path, and for coupling said first communication path to said fourth communication path and said second communication path to said third communication path when a network status signal is received by said selecting means from said network over said first communication path.