SERVICE PROTECTING SWITCHING METHOD, SYSTEM AND DEVICE IN A CONNECTIONLESS NETWORK

• US 20090109843A1
• Filed: 12/05/2008
• Published: 04/30/2009
• Est. Priority Date: 06/05/2006
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: YANG, Faming
• Granted Patent: US 7,848,225 B2
• Time in Patent Office: Days
• US Class Current: 370/225
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 41/06 Management of faults, events, alarms or notifications
• CPC Class Codes: H04L 41/5012 determining service availability, e.g. which services are available at a certain point in time
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/48 Routing tree calculation

Abstract

A method for service protection switching in a connectionless network is provided. The method includes detecting if there is any failure which may have occurred on the respective path in the working flow domain and protection flow domain, coupled between the protection switching point and each of the at least two remote protection switching points. If any failure occurs on a path in one of the working flow domain and the protection flow domain, the service delivered via the failure-occurred path is switched to a path in the other flow domain for further delivery, where the path in the other flow domain is coupled to the remote protection switching point which is located on the failure-occurred path. A system and a device for service protection switching in a connectionless network are further provided such that the protection switching can be done on a path-by-path basis. Accordingly, the flooding problem caused by the protection switching is avoided effectively.

Claims

1. A method for service protection switching in a connectionless network, applicable among a plurality of protection switching points that belong to a same service instance, wherein the plurality of protection switching points are located in a network with protection switching support, including a working flow domain and a protection flow domain, and each protection switching point is coupled to at least two remote protection switching points, and a path exists between the protection switching point and each of its remote protection switching points in the working flow domain and protection flow domain, respectively, and wherein the method comprises:

detecting, by each protection switching point, if there is any failure occurred on each path in the working flow domain and protection flow domain, coupled between the protection switching point and each of the at least two remote protection switching points, wherein if any failure occurs on a path in one of the working flow domain and the protection flow domain, the service delivered via the failure-occurred path is switched to a path in the other flow domain for further delivery, the path in the other flow domain coupled to the remote protection switching point, which is located on the failure-occurred path.

2. The method of claim 1, wherein detecting if there is any failure occurred on each path comprises:

broadcasting, by each protection switching point, a failure detection message periodically to at least two remote protection switching points to which each protection switching point is coupled; and

determining, by each protection switching point, that a failure has occurred on a path in the working flow domain, if the protection switching point has not received the failure detection message broadcasted by the remote protection switching point, from the path in the working flow domain within a predetermined detection time;

determining, by each protection switching point, that a failure has occurred on a path in the protection flow domain, if the protection switching point has not received the failure detection message broadcasted by the remote protection switching point, from the path in the protection flow domain within a predetermined detection time.

3. The method of claim 2, further comprising:

establishing in the working flow domain and the protection flow domain a path forwarding table for all of the protection switching points; and

sending a failure notification message, via the path in the other flow domain, to the remote protection switching point, which is located on the failure-occurred path, when each protection switching point detects a failure occurred on a path in one of the working flow domain and the protection flow domain; and

delivering a service in the service instance, whose destination address is the source address of the failure notification message, via the path in the other flow domain according to the path forwarding table, after receiving the failure notification message from the remote protection switching point.

4. The method of claim 3, wherein the protection switching point is a virtual local area network (VLAN) access point;

and

establishing the path forwarding table comprises;

establishing the path forwarding table by self-learning, according to the destination media access controller (MAC) address contained in the failure detection message;

or

utilizing multiple registration protocol (MRP) to establish the VLAN path forwarding table by registrating unicast address.

5. The method of claim 3, wherein the protection switching point is a virtual local area network (VLAN) access point, and the method further comprises:

configuring information of the network with protection switching support on the VLAN access point, wherein the information of the network with protection switching support comprises;

local information of the VLAN access point, the local information comprising a MAC address of the local VLAN access point, a multicast address of a VLAN access group comprising the local VLAN access point and at least one VLAN access point having the same VLAN ID with the local VLAN access point, and the VLAN ID of the VLAN access group;

remote information of the VLAN access point, comprising a MAC address of at least one VLAN access point in the VLAN access group, excluding the local VLAN access point;

wherein the failure detection message comprises the VLAN ID, destination address and source address of the VLAN access group, wherein the destination address is the multicast address of the VLAN access group and the source address is the MAC address of the local VLAN access point; and

wherein broadcasting the detection message comprises broadcasting the failure detection message according to the VLAN ID, destination address, and source address of the VLAN access group included in the failure detection message.

6. The method of claim 3, wherein the protection switching point is a virtual local area network (VLAN) access point, and the method further comprises:

configuring information of the network with protection switching support on the VLAN access point, wherein the information of the network with protection switching support comprises;

local information of the VLAN access point, the local information comprising a MAC address of the local VLAN access point, a multicast address of a VLAN access group comprising the local VLAN access point and at least one VLAN access point having the same VLAN ID with the local VLAN access point, and the VLAN ID of the VLAN access group;

remote information of the VLAN access point, comprising a MAC address of at least one VLAN access point in the VLAN access group, excluding the local VLAN access point;

the failure notification message comprising the VLAN ID, destination address, and source address of the VLAN access group, wherein the destination address is a MAC address of the remote VLAN access point on the failure-occurred path, and the source address is the MAC address of the local VLAN access point; and

determining the failure-occurred path according to the source address information in the failure notification message, when the VLAN access point receives the failure notification message from the remote VLAN access point.

7. The method of claim 3, wherein the protection switching point is a virtual local area network (VLAN) access point, and the method further comprises:

configuring information of the network with protection switching support on the VLAN access point, wherein the information of the network with protection switching support comprises;

local information of the VLAN access point, comprising a MAC address of the local VLAN access point, a multicast address of a VLAN access group comprising the local VLAN access point and at least one VLAN access point having the same VLAN ID with the local VLAN access point, and the VLAN ID of the VLAN access group; and

remote information of the VLAN access point, comprising;

a MAC address of at least one VLAN access point in the VLAN access group, with the local VLAN access point excluded;

sending, by each VLAN access point, a failure repaired notification message to the remote VLAN access point via the path where a failure was previously detected, if a VLAN access point receives the failure detection message from the remote VLAN access point via the path where a failure was previously detected, wherein the failure repaired notification message comprises the VLAN ID, destination address, and source address of the VLAN access group, the destination address being a MAC address of the remote VLAN access point on the path where a failure was previously detected, and the source address being the MAC address of the local VLAN access point; and

determining, by each VLAN access point, the failure-repaired path according to the source address in the failure repaired notification message, after a VLAN access point receives the failure repaired notification message from the path where a failure was previously detected; and

delivering the service, which was delivered via the path in the other one of the working flow domain and the protection flow domain, via the failure-repaired path.

8. A system for service protection switching in a connectionless network, comprising a working flow domain, protection flow domain and a plurality of protection switching points belonging to a same service instance, wherein the plurality of protection switching points is located in a network with protection switching support, including the working flow domain and the protection flow domain, and each protection switching point is coupled to at least two remote protection switching points, and a path exists between the protection switching point and each of its remote protection switching points in the working flow domain and protection flow domain, respectively, and wherein:

each protection switching point is configured to detect if there is any failure occurred on each path in the working flow domain and protection flow domain, between the protection switching point and each of the at least two remote protection switching points, wherein if any failure occurs on a path in one of the working flow domain and the protection flow domain, the service delivered via the failure-occurred path is switched to a path in the other flow domain for further delivery, the path in the other flow domain coupled to the remote protection switching point, which is located on the failure-occurred path.

9. The system of claim 8, wherein the protection switching point is configured to broadcast a failure detection message periodically to at least two remote protection switching points to which the protection switching point is coupled, and if the protection switching point has not received the failure detection message broadcasted by the remote protection switching point from a path in the working flow domain within a predetermined detection time, it is determined that a failure has occurred on the path in the working flow domain;

and if the protection switching point has not received the failure detection message broadcasted by the remote protection switching point from a path in the protection flow domain within a predetermined detection time, it is determined that a failure has occurred on the path in the protection flow domain.

10. The system of claim 9, wherein the protection switching point is further configured to store a path forwarding table, and when the protection switching point detects a failure occurred on a path in one of the working flow domain and the protection flow domain, the protection switching point sends a failure notification message, via the path in the other flow domain, to the remote protection switching point which is located on the failure-occurred path, and delivers a service in the service instance, whose destination address is the source address of the failure notification message, via the path in the other flow domain, according to the path forwarding table, after receiving the failure notification message from the remote protection switching point.

11. The system of claim 10, wherein:

if the protection switching point receives the failure detection notification message from the path where a failure was previously detected, the protection switching point sends a failure repaired notification message to the remote protection switching point via the path where a failure was preciously detected; and

if the protection switching point receives the failure detection message from the path where a failure was previously detected, the protection switching point determines the failure-repaired path and delivers a service which was delivered via the path in the other flow domain, via the failure-repaired path.

12. A protection switching device belonging to a same service instance along with at least two protection switching devices, wherein each protection switching device is located in a network with protection switching support including the working flow domain and the protection flow domain, and each protection switching device is coupled to at least two remote protection switching devices, and a path exists between the protection switching device and each of its remote protection switching devices, in the working flow domain and protection flow domain, respectively, and wherein the device comprises:

a first module, configured to detect if there is any failure occurred on each path in the working flow domain and protection flow domain, coupled between the protection switching device and each of the at least two remote protection switching devices; and

a second module, configured to switch service which was delivered along the failure-occurred path switched to a path in the other flow domain for further delivery, wherein the path in the other flow domain is coupled to the remote protection switching device which is located on the failure-occurred path.

13. The device of claim 12, wherein the first module broadcasts a failure detection message periodically to at least two remote protection switching devices to which the protection switching device is coupled, and if the failure detection message, broadcasted by the remote protection switching device, has not been received from a path in the working flow domain within a predetermined detection time, it is determined that a failure has occurred on the path in the working flow domain;

and if the failure detection message, broadcasted by the remote protection switching device, has not been received from a path in the protection flow domain within a predetermined detection time, it is determined that a failure has occurred on the path in the protection flow domain.

14. The device of claim 13, wherein if the first module determines that a failure has occurred on the path in the working flow domain, the second module sends a failure notification message to the remote protection switching device on the failure-occurred path via the path in the protection flow domain;

and if the first module determines that a failure has occurred on the path in the protection flow domain, the second module sends a failure notification message to the remote protection switching device on the failure-occurred path via the path in the working flow domain;

wherein the protection switching device further comprises;

a third module, configured to deliver the service, which was previously delivered along the failure-occurred path, along the path in the working flow domain, when receiving the failure notification message from the path in the working flow domain, and deliver the service, which was previously delivered along the failure-occurred path, along the path in the protection flow domain, when receiving the failure notification message from the path in the protection flow domain.

15. The device of claim 14, wherein if the failure detection message has been received from the path where a failure was previously detected, a failure-repaired notification message is sent via the path where a failure was previously detected;

wherein the third module determines if the path in the working flow domain is repaired from the failure, when receiving the failure repaired notification message from the path in the working flow domain, and delivers the service which was delivered via the path in the protection flow domain, via the failure-repaired path in the working flow domain; and

the third module determines if the path in the protection flow domain is repaired from the failure, when receiving the failure repaired notification message from the path in the protection flow domain, and delivers the service which was delivered via the path in the working flow domain, via the failure-repaired path in the protection flow domain.