Method for a network device inserted between point to point connected stations to automatically negotiate communication parameters between the stations

• US 6,907,008 B1
• Filed: 12/21/1999
• Issued: 06/14/2005
• Est. Priority Date: 12/21/1999
• Status: Expired due to Fees

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Trost, Arie, Shvirsky, Yuval, Moskovich, Reuven
• Primary Examiner(s): Ho, Duc
• Assistant Examiner(s): Nguyen, Phuongchau Ba
• Application Number:
  US09/469,982
• Time in Patent Office: 2,002 Days
• Field of Search: 370/238, 370/340, 370/477, 370/282, 370/280, 370/445, 370/446, 370/465, 370/466, 370/438, 370/447, 370/401, 370/296, 370/276, 370/294, 370/462, 370/220, 370/242, 370/449, 370/241, 709/223, 709/224, 709/239, 375/293, 375/220, 375/359, 455/78, 398/9, 714/41
• US Class Current: 370/241
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A network probe inserted between two nodes in point-to-point link synchronizes modes of operation between the two nodes. The probe utilizes IEEE 802.3u Clause 28 Auto-Negotiation to detect and advertise corresponding information regarding modes of operation for the nodes between which it is inserted in the point-to-point link, to achieve a highest priority common mode of operation between the nodes.

Claims

1. A method for a probe to negotiate a common mode of communication between two nodes, comprising:

a) establishing a first communication path between the probe and a first node including negotiating a mode of operation with the first node;

b) establishing a second communication path between the probe and a second node including negotiating a mode of operation with the second node; and

c) controlling a plurality of switches between physical layer interfaces and repeaters using a finite state machine to establish a third communication path coupling the first and second communication paths to provide a negotiated common mode of operation between the first node and the second node.

2. The method of claim 1, wherein controlling the plurality of switches comprises negotiating a speed of a transmission of data over the first communication path between the probe and the first node.

3. The method of claim 1, wherein controlling the plurality of switches comprises negotiating one of half duplex and full duplex communication over the first communication path between the probe and the first node.

4. The method of claim 1, wherein the common mode of operation between the first node and the second node is the best mode of operation available between the first node and the second node.

5. A probe that negotiates a common mode of communication between two nodes, comprising:

means for establishing a first communication path between the probe and a first node including negotiating a mode of operation with the first node;

means for establishing a second communication path between the probe and a second node including negotiating a mode of operation with the second node; and

means for controlling a plurality of switches between physical layer interfaces and repeaters using a finite state machine to establish a third communication path coupling the first and second communication paths to provide a negotiated common mode of operation between the first node and the second node.

6. An article of manufacture comprising a machine readable medium having a plurality of machine readable instructions stored thereon, wherein the instructions, when executed by a processor, cause the processor to:

a) establish a first communication path between a probe and a first node including negotiating a mode of operation with the first node;

b) establish a second communication path between the probe and a second node including negotiating a mode of operation with the second node; and

c) control a plurality of switches between physical layer interfaces and repeaters using a finite state machine to establish a third communication path coupling the first and second communication path to provide a negotiated common mode of operation between the first node and the second node.

7. The article of manufacture of claim 6, wherein the instructions that cause a processor when executed to control the plurality of switches cause the processor when executed to negotiate a speed of a transmission of data over the first communication path between the probe and the first node.

8. The article of manufacture of claim 6, wherein the instructions that cause the processor when executed to control the plurality of switches cause the processor when executed to negotiate one of half duplex and full duplex communication over the first communication path between the probe and the first node.

9. The article of manufacture of claim 6, wherein the common mode of operation between the first node and the second node is the best mode of operation available between the first node and the second node.

10. A probe comprising:

physical layer interfaces coupled to first and second nodes to establish first and second communication paths;

a plurality of switches coupled to the physical layer interfaces and repeaters; and

a finite state machine coupled to the physical layer interfaces to control the plurality of switches to establish a third communication path coupling the first and second communication paths through the physical layer interfaces and at least one of the repeaters, the third communication path providing a negotiated common mode of operation between the first node and the second node.

11. The probe of claim 10 wherein the finite state machine asserts control signals to the switches and enables the repeaters to be used according to a highest common mode of operation between the first and second nodes.

12. The probe of claim 11 wherein the highest common mode of operation is determined by one of a transmission speed and a duplex mode.

13. The probe of claim 10 wherein the finite state machine comprises:

an idle state upon power up;

a first state corresponding to only one of the first and second nodes operating at a low transmission speed; and

a second state corresponding to only one of the first and second nodes operating at a high transmission speed.

14. The probe of claim 10 wherein the finite state machine comprises:

a third state corresponding to both of the first and second nodes operating at a low transmission speed; and

a fourth state corresponding to both of the first and second nodes operating at a high transmission speed.