WO2006131019A1

WO2006131019A1 - A method and site for achieving link aggregation between the interconnected resilient packet ring

Info

Publication number: WO2006131019A1
Application number: PCT/CN2005/000790
Authority: WO
Inventors: Jun Cheng
Original assignee: Utstarcom Telecom Co., Ltd.
Priority date: 2005-06-06
Filing date: 2005-06-06
Publication date: 2006-12-14
Also published as: CN101194473B; CN101194473A

Abstract

A method is provided for achieving link aggregation between the interconnected resilient packet ring (RPR) in the RPR system, and the said interconnection system comprises at least the first RPR and the second RPR, and the said RPR comprises at least two sites crossing the ring. The method comprises the steps: at least two paths crossing the ring are established between the first RPR and the second RPR to transmit the service crossing ring. Wherein a site crossing ring is selected based on the aggregation policy configured to transmit the service crossing ring in the corresponding path crossing ring. The said method and the site of the present invention can automatically transfer the service in this site to the other path crossing ring after certain site or path crossing ring is fail, and wherein the protective time less than 50ms. The service crossing ring has the same CoS in the plurality of RPRs.

Description

Method and site for implementing link aggregation between interconnected resilient packet rings

The present invention relates to the field of Resilient Package Ring (RPR) technology, and in particular to a method for implementing an aggregated link between a plurality of RPR loops, and a cross-ring site.

Background technique

The Resilient Packet Ring is a metropolitan area network technology that uses a dual-ring structure to transfer data between multiple sites. It has been IEEE (The Institute of Electrical and Electronics Engineers) 802. 17 Working group standardization. Key features of the resilient packet ring include the following:

(1) Independent of the transmission medium

The transmission medium constituting the elastic packet ring RPR may be SDH (Synchronous Digital Hierarchy), SONET (Synchronous Optical Network), FDDI (Fiber Distributed Data Interface), or Gigabit (1GE or 10G) and so on;

(2) Support unicast, multicast, broadcast data transmission

For unicast services, the site on the RPR needs to determine whether to strip or forward the packet. For broadcast and multicast services, the site only needs to receive and forward the packet until the source site strips the packet from the ring. There is no need to copy a large number of packets to transfer to different destinations, which greatly saves bandwidth.

(3) Support multiple service levels

I. Class A: Guaranteed minimum delay within the allocated bandwidth;

II. Class B: Guarantees a limited delay within the allocated bandwidth, allowing service at the service level COS (Class of Service) to exceed the allocated bandwidth, at which point the service exceeding the bandwidth is considered to be Class C ( Level C) business is the same;

III. Class C: Try to ensure the delay.

(4) Effective use of loop bandwidth

An RPR ring adopts a dual-ring structure, and two rings constituting the RPR ring simultaneously transmit data, support bandwidth sharing and statistical multiplexing in the ring, and strip the unicast packet at the destination site, so that the bandwidth utilization efficiency of the RPR ring network is obtained. improve. In addition, the RPR ring is also capable of reclaiming allocated bandwidth and re-allocating unused bandwidth. (5) Equity mechanism

When the bandwidth is competed between sites on an RPR loop, the fairness mechanism of the RPk ring can effectively guarantee the fair enjoyment of bandwidth between the competing sites, and enable the competing sites to perform service transmission according to the weights assigned to them.

(6) Plug and Play

RPR's automatic topology discovery mechanism makes it easy to add, delete, and restore sites without any human intervention.

(7) Fast protection switching

RPR provides two fast ring protection switching mechanisms: Wrapping and S teering. Both protection methods achieve a 50-second ring protection time.

For a description of the technical characteristics of the RPR ring network, see ht tp: //www.ieee802.org/17.

Currently, the application of RPR is generally based on the application of a single RPR loop; or the Ethernet/router is connected between multiple rings to implement service switching between multiple loops.

A single loop system, shown in Figure 1, is typically used when there are few services and there is less need to interact or interact with other devices. Figure 1 shows a typical application in IEEE802.17. In Figure 1, RPR ring 10 is a schematic diagram of an RPR loop comprising four sites 101, 102, 103, 104. The device may be a communication device, a switch, a light transmitting device, or a router. The RPR site can be an RPR-enabled switch, a router or an SDH device, or an RPR-only device. Since the present invention relates to at least two RPR rings, the technical features of the single ring are not described in detail herein.

Although a single RPR loop application is a typical application of IEEE 802.17, for a communication involving two or more RPR loops, a single RPR loop cannot provide support, so there is a suitable for two RPRs. The solution for loop interconnection is shown in Figure 2.

In the system of RPR interconnection described in FIG. 2, the RPR ring 21 includes four stations 211, 212, 213, 214; the RPR ring 22 includes four stations 221, 222, 223, 224. In Figure 2, the RPR ring 21 and the RPR ring 22 are interconnected by Ethernet, and the stations 212 and 224 are responsible for the conversion of the Ethernet and RPR frame formats. By interconnecting the two loops 21 and 22 via Ethernet, it is possible to exchange between them. The specific switching operation is performed by two interconnected sites, such as 212 and 224. The traffic between the two rings 21 and 22 can also be exchanged via the switches 24, 26. Switches 24 and 26 can also receive local services from respective local devices 23 and 25, respectively, and send traffic from other sites to the two local devices 23 and 25, respectively.

However, there are significant technical problems with interconnecting RPR loops over Ethernet, namely: The protection of the cross-ring path between stations 212 and 224 is not possible. Because if the cross-ring channel between stations 212 and 224 fails, the exchange of services between RPR rings 21 and 22 is not possible. In addition, if multiple Ethernet connections are made between the two RPR rings 21 and 22, a broadcast storm will result.

In order to solve the problem of broadcast storm and cross-ring protection, a technical solution is to use routers to implement interconnection between RPR rings, as shown in Figure 3. In FIG. 3, ring 310 includes four sites 311, 312, 313, 314; ring 320 includes four sites 321 , 322 , 323 , 324 . In Figure 3, the interconnection between the two RPR rings 310, 320 is accomplished by routers 301 and 302. It is up to router 302 to decide which channel to send the data to. If router 302 fails, router 301 determines which channel to send data to. If the channel between router 302 and RPR ring 310 or RPR ring 320 fails, it is recalculated by router 301, which is the path between router 301 and rings 310 and 320.

However, if the routers 301, 302 are used to implement the cross-ring channel between the RPR rings 310, 320, then when the cross-ring channel fails, the protection time of the cross-ring channel will depend on the protection time of the router, and the protection of the router. The time is above the second level, and the carrier-class protection requirements cannot be achieved. The carrier-class protection time is no more than 50 sec. In addition, through the interconnection technical solution shown in FIG. 3, the service level CoS cannot be guaranteed between the rings 310 and 320. The reason is that the routers between the rings 310 and 320 pass through the router, and the router replaces the information of the data frame, resulting in the adoption of two. Information on the separation level of the layer cannot be passed to another loop.

In view of the above-mentioned deficiencies of the prior art, it is desirable to provide a method and a station capable of reliably implementing cross-ring services across multiple RPR rings and balancing traffic among multiple RPR cross-ring services.

Summary of the invention

The object of the present invention is to provide an application of the RPR interconnection technology, and introduce the advantages of the RPR into the interconnection, and implement link aggregation, which is logically regarded as a cross-ring link aggregation. With carrier-grade protection, it still has the same CoS of the original RPR ring after the cross-ring.

In an aspect of the present invention, a method for implementing link aggregation between interconnected resilient packet rings in a multi-elastic packet ring interconnect system is provided, the interconnect system including at least a first resilient packet ring and a second resilient packet ring The resilient packet ring includes at least two cross-ring sites, and the method includes the following steps: establishing at least two cross-ring channels between the first resilient packet ring and the second packet ring to transmit a cross-ring service; The configured aggregation policy selects a cross-ring site to transmit cross-ring traffic on the corresponding cross-ring channel.

Preferably, the above method further comprises: detecting a cross-ring site failure or a cross-ring channel failure by transmitting a message at intervals between the cross-ring sites located on the same resilient packet ring.

Preferably, in the above method, if a cross-ring site failure or a cross-ring path failure is detected, a cross-ring site is selected according to the configured aggregation policy to transmit the cross-ring service on the corresponding cross-ring channel.

Preferably, the above method further comprises: assigning a unique site identifier to the cross-ring site on the same resilient packet ring.

Preferably, in the above method, the site identifier comprises: a first site identifier for a cross-ring service; and a second site identifier for a local service.

Preferably, in the above method, the first site identifiers are the same.

Preferably, the method further includes: invariably transmitting the service level of the cross-ring service in the first resilient packet ring to the second resilient packet ring.

Preferably, in the above method, the time interval may be configured in the range of 50 to 50000 microseconds.

In another aspect of the present invention, a cross-ring site for implementing link aggregation between interconnected ring-ring packet rings in an elastic packet ring interconnection system is provided, including: a protection policy configuration device, configured to configure site protection The policy determines whether the service level of the cross-ring service is the same as the service level configured by the site itself, and the cross-ring service processing device, configured to selectively send the cross-ring service to the cross according to the judgment result of the protection policy configuration device. On the ring channel.

Preferably, the station further includes state detecting means for detecting whether the other cross-ring stations or the cross-ring channels respectively connected by them are working properly.

Preferably, the state detecting device in the station is further configured to send a message to the resilient packet ring where the site is located at a certain time interval to indicate that the work is working correctly. Often.

Preferably, if the station detects a failure of the cross-ring channel interconnected by it, the message to be sent is set accordingly.

Preferably, if another cross-ring site failure of the same resilient packet ring is detected or a cross-ring channel failure interconnected by the other cross-ring site, the protection policy configuration device selectively modifies the protection policy for the site.

Preferably, the site further includes: a memory, configured to store a site identifier that uniquely identifies itself.

Preferably, the site further includes: a service level filling device, configured to fill the service level of the cross-ring service to the cross-ring service unchanged before the cross-ring service processing device sends the cross-ring service to the cross-ring channel In the frame.

By employing the above method and station of the present invention, the present invention provides the following advantages:

(1) On the interconnection channel, the cross-ring link aggregation technology of the present invention may have multiple channels between multiple RPR rings to achieve link aggregation and protection. If a channel fails, traffic on that channel is automatically transferred to other channels, and there is no broadcast storm problem because there is no loop on the logical topology. For non-cross-ring sites, there is no need to know the existence of a cross-ring site.

(2) In the traffic management, the cross-ring link technology of the present invention enables the cross-ring service to be transmitted on multiple links to achieve the purpose of link aggregation.

(3) In terms of interconnection protection, the cross-ring link technology of the present invention can automatically transfer to other cross-ring channels when the channel fails, and the protection time is less than 50 sec., that is, the protection time has been reached. Carrier-grade protection. This protection is independent of the fast protection technology of RPR technology, which means that it can communicate between multiple RPR rings. In the event of a fault, the protection time can still reach the required standard.

(4) In terms of interconnected CoS, the cross-ring link technology of the present invention can achieve the same CoS between multiple RPR loops for the same service.

In summary, the cross-ring link technology of the present invention fully utilizes the characteristics of the RPR technology, and utilizes the characteristics of the technology, so that the RPR cross-ring service has link aggregation, carrier-class protection, and CoS between RPR loops. Pass.

The RPR interconnection technology of the present invention has the following features:

Expanded functionality without affecting the RPR's own functionality;

Cross-ring services will be assigned to each cross-ring channel according to user policies or automatic policies. On the other hand, the link aggregation purpose is achieved. For the user, the process is transparent and only one logical link is seen.

The cross-ring service is protected, and the protection switching time is less than 50 亳 seconds, which is far lower than the existing technologies;

When the cross-ring channel is protected, other non-cross-ring sites do not care about the corresponding message, and do not need to re-address learning;

The fast switching of the RPR and the switching of the present invention can work together at the same time, and the protection time is not the accumulation of the two guard times, but the longer one.

On the RPR ring, the interconnection site can be anywhere on the ring and does not require the logical location of each of the ring sites;

After the service is interconnected, its CoS can still be retained, with the same on the other loop.

CoS;

For each cross-ring site, the local service can still be carried to achieve site multiplexing. The site ID does not need to be a MAC address, and the unique identifier can be customized. The number of cross-ring channels is not limited.

The cross-ring site ID is not required to be the same on the same RPR ring.

DRAWINGS

The embodiments of the present invention are described by way of example only, and in the claims

1 is a schematic diagram of a technical solution of a single RPR loop of the prior art.

FIG. 2 is a schematic diagram of a technical solution for implementing interconnection between RPR rings by using an Ethernet method in the prior art.

FIG. 3 is a schematic diagram of a technical solution for implementing interconnection between RPR rings by using a router manner in the prior art.

Figure 4 is a schematic illustration of an RPR loop interconnect system in accordance with one embodiment of the present invention. Figure 5 is a schematic diagram illustrating the transmission of a message in accordance with a preferred embodiment of the present invention.

Figure 6 is a flow diagram illustrating the process of processing a message in accordance with a preferred embodiment of the present invention.

Figure 7 illustrates a schematic diagram of cross-ring service aggregation between RPRs.

Figure 8 illustrates a schematic diagram of failure protection at an RPR cross-ring site in accordance with an embodiment of the present invention. Figure 9 illustrates a schematic diagram of fail-safe protection of an RPR interconnect channel in accordance with an embodiment of the invention. detailed description

4 is a schematic diagram of an RPR ring interconnection system in accordance with one embodiment of the present invention. The RPR ring interconnect system shown in Figure 4 includes two RPR rings 410 and 420. The RPR ring 410 includes four sites 411, 412, 413, 414; the RPR ring 420 includes four sites 421, 422, 423, 424. The RPR site can be an RPR-only device, or an RPR-enabled switch, router, or SDH.

It should be noted that although the RPR ring interconnection system depicted in FIG. 4 includes two RPR rings, in practice, one RPR ring interconnection system may include more than two RPR rings, and may include multiple RPR rings, but at least There are two RPR rings to form an RPR ring interconnect system. Otherwise, it is the application technology scheme of the single loop of Figure 1.

It should also be noted that although only four stations are drawn on each RPR ring shown in FIG. 4, those skilled in the art should understand that the number of sites in the RPR ring of the present invention is not limited to four, specific The number of numbers is determined based on actual business needs. There may be multiple sites on each RPR ring. Of course, the number of sites on the rings 410, 420 may be the same or may not be the same. However, there should be at least two sites on each RPR, otherwise there is no practical meaning to an RPR ring that includes only one site.

The RPR ring has an automatic topology feature. Whenever a station is added or revoked in the RPR ring 410, 420, the RPR ring 410, 420 can automatically recognize the newly added site and the cancellation of the existing site, so that it is not required Any artificial intervention.

Figure 4 shows a schematic of a system for implementing RPR interconnections using different site IDs. As shown, RPR ring 410 and RPR ring 420 are interconnected by sites { 411, 421 } , { 412 , 424 } and { 413 , 423 }, where sites 411 and S are combined together into one RPR device, the RPR device It can be a switch with RPR function, a router, an SDH device, etc., where S represents a switch, router, SM, and other functions other than the RPR function. The invention is based on the RPR and uses the frame format of the RPR to adopt different site IDs for the cross-ring service and the non-cross-ring service, so that the local service and the cross-ring service are transmitted on the RPR. There are two source identifiers, SID (Source Indent if i cat ion ), for each internet site. For the site 411, for the local service, its ID is ID2; for the cross-ring service, its ID is ID1. For site 412, the ID for the local service is ID4; for the cross-ring service, the ID is ID3. For the site 413, the ID of the local service is ID9; for the cross-ring service, the ID is ID8. For the site 421, the ID of the local service is ID6; for the cross-ring service, the ID is ID5. For site 423, the ID for the local service is ID 11; for the cross-ring service, the ID is ID 10. For site 424, for cross-ring services, the ID is ID 7. It should be noted that although the site identifier of the local service of station 424 is not identified in FIG. 4, it does not mean that site 424 may not receive local traffic and send local traffic to the local device. Because in nature, the cross-ring site is the same. On the RPR ring 410, all services that need to be sent to the RPR ring 420 have a destination site address of ID1 (the site identifier of the site 411 for the cross-ring service) or ID3 (the site identifier of the site 412 for the cross-ring service) or ID8 (site identifier of site 413 for cross-ring service) (specifically, which ID is selected by the sending station at the time); for all local services destined for 412, the destination ID is ID 4. By analogy, the site identifier of the local service destined for the site 411 is ID2, the site identifier of the local service destined for the site 413 is ID9, and the site identifier of the local service destined for the site 421 is ID6, sent to the site 423. The site identifier for the local service is ID11.

It should also be noted that although only three cross-ring channels connecting two RPR rings are drawn in FIG. 4, the number of cross-ring channels between two RPR rings is not limited to three, and may be two or Two or more, preferably two or more. The exact number of cross-ring channels depends on the actual cross-ring traffic. The interconnection channel may be connected in a wired manner, such as a network such as the Internet, or may be connected in a wireless manner. The interconnection channel may be, for example, a coaxial cable, an optical fiber, or the like, and may also have an interconnection network between the interconnection channels.

It should be noted that the cross-ring sites shown in FIG. 4 are adjacent in position, but embodiments of the present invention do not require that the stations must be adjacent, and the cross-ring sites may be in any of the RPR rings. Location. Preferably, the cross-ring sites may be arranged to be adjacent in position, because if one of the sites fails, the cross-ring service packets may have the same path as the original path if the sites are adjacent to each other. If the site is not set to be adjacent, the path to be taken by the cross-ring service may become longer, so that the time taken by the cross-ring service from the source site to the destination site becomes longer.

The cross-ring site 412 on the RP ring 410 includes (actually, each of the cross-ring sites also includes): receiving means for receiving service data; and service type determining means for determining that the service data received by the receiving device is What type of service is the local ring business, the cross-ring business or the local business. If it is a local ring service, the service data is sent to the local ring service processing device included in the site 412, and is used for RPR processing and transmission of the service that needs to be sent to the RPR ring 410. If the received business data is a cross-ring business, Transmitting the cross-ring service to the service level filling device, and filling the service level COS information of the ring into the cross-ring service frame, and then sending the filled cross-ring service frame to the cross-loop service processing device, where Processing the cross-ring service and transmitting it to the cross-ring channel 440, and then to the RPR ring 420; if the received data service is a local service, transmitting the service data to the local service processing device, where After the service data is processed by the local service processing device, the processed service data is sent to the local device.

43. The cross-ring site 412 also includes state detection means for detecting that other cross-loop sites on the ring, such as 412, 413, and the cross-ring channels 440, 450 that they are responsible for are functioning properly. The cross-ring site 412 also includes a protection policy configuration device for configuring a protection policy of the site, and determining a service level of the cross-ring service received from the receiving device, if the service level of the received cross-ring service is assigned to itself If the protection level is the same, the cross-ring service is processed, otherwise the cross-ring service is placed on the ring 410.

Regarding the above-mentioned site identifiers, the site identifiers can be identified by media access control sub-layer MAC (Media Access Control) addresses for different services. Of course, other addresses or methods may also be used as the identifier ID of the identification site, or an identification method may be customized, as long as one site can be uniquely identified. Each site's own site identifier ID is stored in its own memory. The memory that each site has can be implemented in various forms of readable and writable memory. For site IDs of each cross-site site, they are not required to be inconsistent. From a simple point of view, using the same ID makes it easier to implement.

The following is an example of a cross-ring site 411. Normally, after receiving the service from the cross-ring channel 430, the site 411 will be encapsulated according to the RPR frame format, and the source address of the RPR frame header is filled with the ID1 _D pair of service data from the local device 41. It is encapsulated into ID2 in the RPR frame header. The station 411 receives all the data frames whose destination stations are ID2, and receives the data frames whose destination stations are ID1. The data frame for ID2 will not be sent to the cross-ring channel, and the data frame for ID1 will only be sent to the cross-ring channel. Similarly, stations 412, 413, 421, 423, and 424 perform similar operations. For the site 414, different services are sent to sites with different site identities according to the self-learning address.

For non-cross-ring sites, such as site 414, multicast or multicast frames will be sent on RPR ring 410 when no address is found for the cross-ring site, such as site 412. The cross-ring sites 411, 412, and 413 will receive broadcast/multicast frames according to policies. This strategy is configurable, for example, according to the RPR traffic classification principle, MAC address, Ethernet frame VLAN ( Virtua l Loca l Area Network Virtual Area Network ID, Internet Protocol IP Address, etc. are configured. Determine whether to receive the service according to the configured principle. If the service needs to be received, it is sent to the cross-ring channel. If the service is not required to be received, it is not processed and forwarded directly to the next site. Taking the RPR flow classification principle (level A/B/C) as an example, the station 411 can be set to receive the service of level A, and the station 412 is set to receive the non-type A service and the like. . For example, if the service carried by the VLAN ID policy is an Ethernet service, the site 411 can be configured to receive only services with a VLAN ID less than 1000, and the site 412 can be configured to receive services with a VLAN ID greater than or equal to 1000.

A cross-ring site monitoring mechanism is run on each of the cross-ring sites, such as sites 411, 412, 413 on the RPR ring 410, to maintain communications for discovering the status of other cross-ring sites on the RPR loop 410 and detecting whether other sites are functioning properly. .

When a cross-ring site such as site 412 fails or a cross-ring channel such as channel 440 fails, other cross-ring sites will detect the failure through a monitoring mechanism and automatically run a policy to transfer the traffic of the cross-ring channel to the designated site for reception. And send. This policy is also configurable and can be determined by site conversion priority or by site ID size. With the cross-ring site monitoring mechanism, it is guaranteed that the service protection time will be less than 50 sec. When there are three or more cross-ring sites, you need to configure a protection priority policy, which is used by which site in the remaining cross-ring sites to receive and process the fault cross-loop after a cross-ring site fails. Site business. For example, the protection priority policy is set according to the site ID size. The ID value has a high priority and the ID value has a low priority. Then, when a site fails, the service handled by the faulty site is received and processed by the site with the largest ID value in the remaining sites.

In a preferred manner, the cross-ring site includes a timer for timing that is initiated only after a normal cross-ring site detects a failed cross-ring site recovery. It is assumed here that the site 411 is a failed site, 12 is a normal cross-ring site, and after the site 411 fails, the cross-ring service to the site 411 is received. When the station 412 detects that the station 411 has returned to normal, it activates the timer it has and sets an initial time for the timer. The timer starts counting down the initial time. When the set initial time reaches zero before the station 411 itself becomes the identity that can receive the service, the station 41 ² sends a message to the station 411 to request the site. 411 Restore the identity of the original site. If the original cross-ring site fails again before the set time has not reached zero, the timer is stopped, and the timer is reactivated and reset initially when the original site is detected to be restored again. Between.

Figure 5 is a schematic diagram illustrating the transmission of a message in accordance with a preferred embodiment of the present invention. As described in conjunction with FIG. 4, a cross-ring site monitoring mechanism is run on each of the cross-ring sites 411, 412, 413, 421, 423, 424 to maintain communications, thereby discovering the status of other cross-ring sites on the RPR loop and detecting Whether other sites work properly. In a preferred embodiment, the detection mechanism is implemented by a message mechanism, in particular by sending a message between the cross-ring sites 411, 412, 413, 421, 422, 423, 42. According to the preferred embodiment, the message includes three types of messages, MSG-A 51, SG-B 52, and MSG-C 53. Referring to Figure 5, MSG-A 51 represents a keepAlive message between the cross-ring sites on the same RPR. MSG-B 52 represents a keepAl ive message with a cross-ring site, which may be a switch, a router, an SDH, or the like. MSG—C 53 represents the KeepAl ive message between Sxs at both ends of the cross-ring channel. Among them, MSG-B 52 and SG-C 53 recommend the use of existing Sx-related protocols, such as LACP (Link Aggregation Control Protocol) or hardware support. Since the above-described MSG_B 52 and MSG-C 53 are not related to the subject matter of the present invention, they will not be described in detail herein. For RPR ring 410, cross-ring sites 411, 412, 413 periodically send MSG_A messages, which contain status fields that work properly across the ring channel. The frequency of sending MSG-A 51 to each cross-ring station is 50 ~ 50000 microseconds. The quality of the cross-loop channel is detected by the corresponding device, and the status field in the MSG-A 51 frame is set according to the quality of the detected channel information. The above MSG-A message is sent between the various ring sites in the same ring.

For example, the station 410 in the ring 410 is illustrative. The station 410 periodically sends an MSG-A 51 message to the ring 410. Accordingly, the cross-ring sites 412, 413 also periodically send MSG-A 51 messages to the ring 410. When the station 411 does not receive the MSG-A 51 message from the station 412 within a certain interval, the station 412 is considered to be malfunctioning. If the status field in the MSG_A 51 message received from the station 412 at the station 411 indicates that the cross-ring channel 440 interconnected by the station 412 has failed, it is determined whether the station 411 or the station 413 is responsible for transmitting the station identification according to the protection priority policy configured above. Cross-ring business for ID3. For services with site ID ID4, there is still site 412 to process and send to local site 43.

6 is a flow chart illustrating the process of processing a message in accordance with a preferred embodiment of the present invention. Take RPR 410 as an example to illustrate this process. The process begins in step S601. Then, the process proceeds to step S602, in which the cross-ring site 411 is taken as an example for explanation. The state detecting means of the cross-ring site 411 receives the MSG_A message 51 from the cross-ring sites 412, 413. If the state detecting means of the cross-ring site 411 has not received the MSG-A message 51 from the cross-ring sites 412, 413 within a certain period of time, the process proceeds to step S604. At step S604, the cross-ring site 411 determines that the station from which the MSG-A message 51 was not received has failed. The certain time is configurable, ranging from 50 microseconds to 50,000 microseconds, with a preferred value being 2000 microseconds. In the RPR ring 410, for the station 411, it is detected that the station 412 or 413 has failed, and then the process proceeds to step S606. If the state detecting means of the cross-ring site 411 receives the MSG_A message 51 from the cross-ring sites 412, 413 within a certain time, it is determined that the cross-ring sites 412, 413 are operating normally. Then, the process proceeds to step S603. In step S6 Q3, the state detecting means of the cross-ring site 411 checks the status field from the received MSG_A message 51 to determine whether the cross-ring channel 440 or 450 is operating normally. If the status field in the MSG_A message 51 indicates that any of the cross-ring channels 440, 450 responsible for the cross-ring sites 412, 413 has failed, the process proceeds to step S605. At step S605, the cross-ring site 411 determines that a failure has occurred in the cross-ring channel. Then, the process proceeds to step S606, in which it is determined whether the cross-ring service of the faulty site should be received in place of the faulty site according to the set protection switching priority policy. If not, proceed to step S602; if necessary, proceed to step S607. At step S607, the service of the failed site will be received, and then the process proceeds to step S602.

In the above process, when the cross-ring site 411 determines that the cross-ring site 412 fails or the cross-ring channel 440 that is responsible for the cross-ring site 412 fails, the cross-ring service sent to the destination ID ID3 is received locally according to the policy. .

For the cross-ring service, the cross-ring sites 411, 412, and 413 are all classified by the service level filling device to the service level CoS (level A/level B level C) of the cross-ring service on the RPR ring 410. The packet is sent to the frame header of the cross-ring service, and then sent to the cross-ring service processing device. After processing, the cross-ring service is transmitted to the ring 420. Then, the frame header is parsed by the cross-ring sites 421, 424, and 423 of the RPR ring, and then the service level on the ring 410 is mapped into the classification information of the RPR to realize the sharing of the service level CoS.

FIG. 7 illustrates a schematic diagram of performing cross-ring service aggregation between RPRs. Figure 7 illustrates, by way of example, the transmission of cross-ring traffic over interconnected RPR rings. Points a, b, and c in Figure 7 It does not represent three cross-ring services from site 414 to site 422, and represents three types of services of service class A, B, and C on RPR ring 410. The three pairs of cross-ring sites (411, 421), (412, 424), (413, 423) are set to transmit the level A, level B, and level C services respectively, and set the three pairs of cross-ring sites to switch the path priority to 3. , 2, 1. It should be noted that the setting protection policy herein is for illustrative purposes only and is not intended to be limiting.

For the cross-ring service a, the cross-ring site 411 respectively puts the classification information of the service level CoS (including the service levels A, B, and C) of the ring into the frame header of the cross-ring service a, and transmits the information to the cross-ring channel 430 through the cross-ring channel 430. RPR loop 420. The cross-ring site 421 on the RPR loop 420 parses the frame header and maps it to the RPR classification information to implement CoS sharing. For the cross-ring business b, c do the same,

It is assumed here that the cross-ring site 411 of the RPR ring 410 will only receive the traffic of the level A according to the configuration and send it to the RPR ring 420. After receiving the traffic from the interconnected channel at the cross-ring site 421 of the RPR ring 420, the RPR is normal. The process proceeds, in this case also the service a is sent to the site 422 of the RPR ring 420. Similarly, the services b, c will be received by the site 412 and the station 413 and sent to the RPR ring 420 on the RPR ring 410, respectively. It can be seen from FIG. 7 that the RPR ring 410 has three cross-ring services a, b, and c, but the three services respectively reach the RPR ring 420 through different interconnecting channels, instead of reaching the RPR through a cross-ring channel. Ring 420, that is, link aggregation is implemented between rings 410 and 420 in the present invention, and multiple links are aggregated to form a logical link. Since there is only one link logically across the link, there is no broadcast storm.

Figure 8 illustrates a schematic diagram of failure protection at an RPR cross-station site in accordance with an embodiment of the present invention. FIG. 8 illustrates, by way of example, the processing of the cross-ring service when the cross-ring site 411 fails. Of course, this is just a case of site 411, and every cross-ring site has the possibility of failure. As shown in Figure 7, services a, b, c represent the three-way cross-ring service from site 414 to site 422. Under normal circumstances, traffic a arrives at RPR ring 420 via cross-ring channel 430 between stations 411 and 421; service c arrives at RPR ring 420 via cross-ring channel 440 between stations 412 and 424; traffic c is between stations 413 and 423 The cross-ring channel 450 reaches the RPR ring 420.

In FIG. 8, cross-ring site 411 periodically receives MSG_A messages 51 from stations 412 and 413 to determine if cross-ring sites 412 and 413 are faulty, and similarly, cross-ring sites 412 will periodically receive from cross-ring sites 411 and 413. The MSG-A message, the cross-ring site 413 periodic line receives MSG_A messages from the cross-ring sites 411 and 412. If the shape of 412 and 413 If the state detecting device does not receive the MSG-A 51 message from the cross-ring site 411 within the specified time, the 411 site is considered to be faulty, and it is assumed that the set switching priority of the protection switching priority 412 is higher than 413, according to the setting. Protection switching priority 412 The station will receive the service received by the original 411 station, that is, the service whose destination ID is ID1, and the cross-ring station 412 will still receive the original service, that is, the service whose destination station ID is ID3, that is, the service will be received at the same time. , b, and sent to the RPR ring 420 through the cross-ring channel 440. Site 411 and S1 are combined into one RPR device. The RPR device can be an RPR-enabled switch, router, SDH device, etc., where S represents switches, routers, SDH, and other functions other than RPR functions. After the connection between 411 fails, it is necessary to tell s2 (using MSG_B and MSG-C message delivery), on the RPR ring 420, 421 will detect the cross-ring channel failure through the MSG-B message, and then, the processing flow of FIG. 7 is performed. After this processing, the cross-ring business achieves the purpose of protection. In the topology of Figure 8, since the site 411 fails, the RPR protection module will be started, and all services passing through the site 411 will follow the latest topology, and the new transmission direction, that is, the services a, b will not go in the original ring direction. As shown in Figure 8. That is, in this embodiment, both the RPR protection and the cross-ring protection of the present invention work simultaneously, wherein the RPR protection startup and the cross-ring protection startup both protect the service a, since the RPR protection and the cross-ring protection are simultaneously activated. Since the RPR protection time is less than 50 sec and the cross-ring protection time is less than 50 sec., the two protections are independent of each other, so the protection time of the service a is less than 50 sec.

Figure 9 illustrates a schematic diagram of FPR cross-channel failure protection in accordance with an embodiment of the invention. Figure 9 illustrates, by way of example, the case where the cross-ring channel 430 fails for cross-ring traffic and local traffic processing. As shown in Figure 7, services a, b, and c represent three cross-ring services from site 414 to site 422. Under normal circumstances, traffic a arrives at RPR ring 420 via cross-ring channel 430 between stations 411 and 421; traffic b reaches RPR ring 420 via cross-ring channel 440 between stations 412 and 424; traffic c is between stations 413 and 423 The cross-ring channel 450 reaches the RPR ring 420.

In FIG. 9, cross-ring site 411 periodically receives MSG_A messages 51 from stations 412 and 413 to determine if cross-ring sites 412 and 413 are faulty, and similarly, cross-ring sites 412 will periodically receive from cross-ring sites 411 and 413. The MSG-A message, the cross-ring site 413 periodic line receives the MSG-A messages from the cross-ring sites 411 and 412. Site 411 detects a cross-ring failure, sets the status field in the MSG_A 51 frame to channel failure, then transmits it, and stops receiving the frame with the destination ID ID1, service a. Sites 412 and 413 receive The MSG-A 51 frame to the site 411 is processed according to the flow of FIG. 6, and the cross-ring channel on the site 411 is detected to be invalid. According to the set protection switching policy, the priority of the site 412 is higher than 413, according to the setting. The protection switching priority, the site 412 will receive the service received by the site 411, that is, the service whose destination ID is ID1, and the cross-ring site 412 will still receive the original service, that is, the service whose destination site ID is ID3, that is, the service will be received at the same time. a, b, and sent to the RPR ring 420 through the cross-ring channel 440. The same processing is performed at stations 421, 422 on the RPR ring 4'20. After this process, the cross-ring business achieves the purpose of protection.

It should be noted that the above-described embodiments are illustrative of the invention and are not intended to be limiting, and that many alternative embodiments can be devised without departing from the scope of the appended claims.

Claims

Rights request

A method for implementing link aggregation between interconnected resilient packet rings in a multi-elastic packet ring interconnect system, the interconnect system comprising at least a first resilient packet ring and a second resilient packet ring, the resilient packet ring being at least The method includes two cross-ring sites, and the method includes the following steps:

Establishing at least two cross-ring channels between the first resilient packet ring and the second packet ring to transmit the cross-ring service;

It is characterized by:

Select a cross-ring site based on the configured aggregation policy to upload cross-ring services on the corresponding cross-ring channel.

The method of claim 1, further comprising: detecting a cross-ring site failure or a cross-ring channel failure by transmitting a message at intervals between the cross-ring sites located on the same resilient packet ring.

3. The method of claim 2, wherein if a cross-ring site failure or a cross-ring channel failure is detected, selecting a cross-ring site according to the configured aggregation policy to transmit the cross-ring service on the corresponding cross-ring channel.

The method of any of claims 1-3, further comprising: assigning a unique site identifier to the cross-ring site on the same resilient packet ring.

The method of claim 4, wherein the site identifier comprises: a first site identifier for a cross-ring service; and a second site identifier for a local service.

6. The method of claim 5 wherein the first site identifier is the same as other cross-ring sites on the same resilient packet ring.

The method of any of claims 1-3, further comprising: invariably transferring the service level of the cross-ring service in the first elastic packet ring into the second resilient packet ring.

The method of any of claims 2-3, wherein the time interval is configurable between 50 and 50000 microseconds.

9. A cross-ring site for implementing link aggregation between interconnected resilient packet rings in a resilient packet ring interconnect system, comprising:

a protection policy configuration device, configured to configure a protection policy of the site and determine whether the service level of the cross-ring service is the same as the service level configured by the site itself;

a cross-loop service processing apparatus, configured to configure a judgment result of the device according to the protection policy The selective cross-ring service is sent to the cross-ring channel.

10. The station of claim 9, wherein the station further comprises a status detecting device for detecting whether the other cross-ring stations or the cross-ring channels respectively interconnected by them are working properly.

11. The station of claim 10, wherein the status detecting means is further configured to send a message to the resilient packet ring on which the station is located at a certain time interval to indicate whether the station is functioning properly.

The station according to claim 11, wherein if the station detects that a cross-ring channel interconnected by it fails, the message to be transmitted is set accordingly.

The station according to any one of claims 10 to 12, wherein if another cross-ring site failure of the same resilient packet ring is detected or a cross-ring channel failure interconnected by the other cross-ring site is detected, The protection policy configuration device selectively modifies the protection policy of the site.

14. The station of any of claims 11-12, wherein the time interval is configurable at 50 50000 microseconds.

15. The site of claim 9 further comprising: a memory for storing a site identifier that uniquely identifies itself.

16. The station of claim 15, wherein the site identifier comprises: a first site identifier for cross-ring services;

Second site identifier for local business.

17. The station of claim 16, wherein the first site identifier is the same as a first site identifier of other cross-ring sites on the same resilient packet ring.

The station according to claim 9, further comprising: a service level filling device, configured to change a service level of the cross-ring service before the cross-ring service processing device sends the cross-ring service to the cross-ring channel Populate into a cross-loop frame.