Concentrator and reset control method therefor

• US 20030224827A1
• Filed: 02/10/2003
• Published: 12/04/2003
• Est. Priority Date: 05/17/2002
• Status: Active Grant

• Current Assignee: Allied Telesis Holdings KK
• Original Assignee: Allied Telesis Holdings KK
• Inventors: Chiba, Hideaki
• Granted Patent: US 7,263,104 B2
• Time in Patent Office: Days
• US Class Current: 455/561
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 41/0681 Configuration of triggering conditions
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 49/557 Error correction, e.g. fault recovery or fault tolerance

Abstract

There is provided a concentrator and its reset control method that may easily and reliably secure early restoration from an outage of network communications. A concentrator to which a plurality of network devices are connectible includes a communication control part for controlling a transfer process of information among the network devices, a condition determination part for determining whether information obtained from the communication control part satisfies a reset condition, and a reset control part for controlling a reset signal used to reset the communication control part based on a determination by the condition determination part.

Claims

1. A concentrator to which a plurality of network devices are connectible, said concentrator comprising:

a communication control part for controlling a transfer process of information among the network devices;

a condition determination part for determining whether information obtained from said communication control part satisfies a reset condition; and

a reset control part for controlling a reset signal used to reset said communication control part based on a determination by said condition determination part.

2. A concentrator according to claim 1, wherein the reset control part selectively resets part of a circuit in said communication control part.

3. A concentrator according to claim 1, wherein the reset control part resets said communication control part entirely.

4. A concentrator according to claim 1, wherein the reset condition includes time information, and said concentrator includes a timer for measuring the time information.

5. A concentrator according to claim 1, wherein said condition determination part is connected to said communication control part and includes a hardware status monitoring part for detecting a status of hardware including said communication control part and said network devices.

6. A concentrator according to claim 1, wherein said condition determination part is connected to said communication control part and includes a software status monitoring part for detecting a status of software of said communication control part.

7. A concentrator according to claim 1, wherein the reset condition is set variably.

8. A concentrator according to claim 1, further comprising:

a controller for controlling each component in the concentrator; and

a non-volatile memory for storing a status of said controller before said communication control part is reset.

9. A concentrator according to claim 1, further comprising a non-volatile memory for storing the reset condition.

10. A method for controlling resetting of a concentrator to which a plurality of network device are connectible, said method comprising the steps of:

determining whether at least one of a communication control part and a timer has generated a signal that satisfies a predetermined reset condition, the communication control part controlling a transfer process of information among the network devices; and

generating a signal for resetting the communication control part when said determining step determines the reset condition has been satisfied.

11. A method according to claim 10, wherein said generating step generates a signal for selectively resetting part of a circuit in the communication control part.

12. A method according to claim 10, wherein the reset condition includes an occurrence of one event or simultaneous occurrences of multiple events.

13. A method according to claim 10, wherein the reset condition includes an occurrence of a collision between the network devices, and a change of a link on state indicative of a communication availability between the concentrator and the network device into an off state.

14. A method according to claim 10, wherein the reset condition includes time-sequential occurrences of multiple events.

15. A method according to claim 10, wherein the reset condition includes a start of a communication active state indicating that a packet is being received through one port connected to the network device, and a lack of update of a number of packets received at the port within a certain period.

16. A method according to claim 10, wherein the reset condition includes a start of a communication active state indicating that a packet is being transmitted through one port connected to the network device, and a lack of update of a number of packets transmitted at the port within a certain period.

17. A method according to claim 10, wherein the reset condition includes a start of a communication active state indicating that a packet is being transmitted through one port connected to the network device, an update of the number of packets received at the port within a certain period, and a lack of update of the number of packets transmitted at the port within a certain period.

18. A method according to claim 10, wherein the reset condition includes a transmission of a pause packet signal longer than a prescribed period from one port connected to the network device, the pause packet signal requesting a stop of sending the packet.

19. A method according to claim 10, wherein the reset condition includes an update of a number of packets within a certain period received at one port connected to the network device, and a lack of release or allocation of a buffer for temporarily storing the packet, within a certain period.

20. A method according to claim 10, wherein the reset condition includes a lack of an action longer than a prescribed period.

21. A method according to claim 10, wherein the reset condition includes a continuation of an erroneous event longer than a prescribed period.

22. A concentrator for use with a local area network, said concentrator including a plurality of ports, and serving to monitor a communication status, said concentrator comprising:

specific reset activating means for activating a specific reset function different from a reset at the time of power-on, and for previously determining whether the specific reset function activates when the specific trigger condition is met;

means for designating and varying one or more various specific trigger conditions; and

a non-volatile memory for storing a designated status of a controller when the specific reset function activates,

wherein said non-volatile memory maintains memory contents during an action of the specific reset function and the reset at the time of power-on, providing said concentrator with an automatic restoration function at the time of obstructions.

23. A concentrator according to claim 22, wherein the specific trigger condition is so programmable that the specific trigger condition may designate an occurrence of one event or simultaneous occurrences of multiple events at the same timing, or an occurrence of one event or simultaneous occurrences of multiple events at each timing of time-sequential multiple timings, respective time-sequentially occurring events being able to be designated as the same event or different events at each timing, and a condition between time-sequentially occurring events being able to be designated.

24. A concentrator according to claim 22 or 23, wherein the specific reset function may designate so as to simultaneously reset all of communication functions in the concentrator or so as to reset part of a communication control function in the concentrator, these operations being conducted in accordance with setting of the specific trigger conditions.

25. A concentrator according to claim 22 or 23, wherein the specific reset function may reset a communication control function relating to one or more communication ports for which the specific trigger condition occurs.

26. A concentrator according to claim 22 or 23, wherein setting of the specific trigger condition may reset a reception port or transmission port or simultaneously reset all of communication functions in said concentrator when the port does not perform a receiving action or a transmitting action longer than a designated prescribed time as a result of that the communication status is monitored.

27. A concentrator according to claim 24 or 25, wherein the specific trigger condition designates control error types and a continuous occurrence of the control error for a designated period beyond a prescribed time, the specific reset function activating when the control error occurs over the designated period.