Method and apparatus for loop breaking on a serial bus

• US 6,977,887 B1
• Filed: 06/17/2003
• Issued: 12/20/2005
• Est. Priority Date: 07/09/1999
• Status: Expired due to Term

• Current Assignee: Apple Computer Incorporated (Apple Inc.)
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Whitby-Strevens, Colin, Hauck, Jerrold Von
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US10/464,246
• Time in Patent Office: 917 Days
• Field of Search: 370/216, 370/241, 370/254, 370/232, 370/252, 370/316, 709/224, 709/232, 710/107, 710/224, 710/104
• US Class Current: 370/216
• CPC Class Codes: H04L 12/40078 Bus configuration home automation networks H04L12/2803; arrangements for maintenance or administration H04L41/00
• CPC Class Codes: H04L 12/6418 Hybrid transport

Abstract

A method for loop breaking includes selecting a first port of a node, transmitting a first packet containing a first identifier from the first port of the node, listening for a second packet containing a second identifier for a period of time on a second port of the node, joining the first port and the node if the second identifier meets a first criteria with respect to the first identifier and quarantining the first port when the second identifier meets a second criteria with respect to the first identifier.

Claims

1. In a system including at least one bus, each said bus including at least one node, each said node including at least one port, a method for loop breaking, said method comprising:

transmitting a first packet on a bus attached to a first port of said node, said first packet containing a unique identifier;

listening for a second packet for a period of time on a second port of said node, said second packet containing said unique identifier;

joining said first port to said node if said second packet is not received within said period of time; and

quarantining said first port if said second packet is received within said period of time.

2. A computer-readable medium containing instructions which, when executed by a computer, performs loop breaking in a system including at least one bus, each said bus including at least one node, each said node including at least one port, said instructions comprising:

transmitting a first packet on a bus attached to a first port of said node, said first packet containing a unique identifier;

listening for a second packet for a period of time on a second port of said node, said second packet containing said unique identifier;

joining said first port to said node if said second packet is not received within said period of time; and

quarantining said first port if said second packet is received within said period of time.

3. A computer-readable medium containing instructions which, when executed by a computer, performs loop breaking in a system including at least one communications bus, each said bus including at least one node, each said node including at least one port, said instructions comprising:

transmitting a first packet on said first bus from a first port of said node, said first packet containing a unique identifier;

listening for a second packet for a period of time on a second port of said node, said second port operatively coupled to a second bus, said second port not operatively coupled to said node, said second packet containing said unique identifier, joining said second port to said node if said second packet is not received within said period of time; and

quarantining said second port if said second packet is received within said period of time.

4. A computer-readable medium containing instructions which, when executed by a computer, performs loop breaking in a system including at least one communications bus, each said bus including at least one node, each said node including at least one port, the instructions comprising:

transmitting a first packet on said first bus from a first port of said node, said first packet including a first identifier;

listening for a second packet for a first amount of time on a second port of said node, said second packet including a second identifier;

joining said first port and said node if said second identifier meets a first criterion with respect to said first identifier;

surrendering control of said first bus if said second identifier meets a second criterion with respect to said first identifier; and

quarantining said first port if said second identifier meets a third criterion with respect to said first identifier.