CN100502336C

CN100502336C - City domain Ethernet network bridge, system and method for providing service

Info

Publication number: CN100502336C
Application number: CNB2006100608826A
Authority: CN
Inventors: 于德雷
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2006-05-24
Filing date: 2006-05-24
Publication date: 2009-06-17
Anticipated expiration: 2026-05-24
Also published as: CN101043395A

Abstract

The disclosed Ethernet edge bridge comprises a bridging member including a US port, a NS port and a transmission entity. It also discloses a MAN system including a user bridge network and a provider backbone network. Wherein, the user bridge network connects with the backbone network, and the latter connects with each other through the bridge network. This invention also discloses the method for providing service on edge of the MAN, which comprises: the user bridge network accesses with the US port of MAC-in-MAC edge bridge; the US port builds mapping table between the virtual user ID and provider business, and the MAC-in-MAC edge bridge completes the business mapping or port mapping according to data message and mapping relation.

Description

Metro Ethernet network bridge, system and method for providing service

Technical Field

The present invention relates to the field of metro ethernet technology, and in particular, to a metro ethernet bridge, system and method.

Background

Ethernet (Ethernet) originally was a Local Area Network (LAN) technology that evolved through the process from HUBs (HUBs) to bridges (bridges) to Virtual Local Area Network (VLAN) technologies. The VLAN technology inserts a TAG (TAG) after a Destination Address (DA) and a Source Address (SA) of an ethernet data packet, and divides the ethernet data packet into different flow domains by using a 12-bit Virtual identifier (VID, Virtual ID) in the TAG, so that a plurality of (up to 4K) Virtual local area networks can be logically established on one physical local area network, and typically, an ethernet packet with the TAG adopts the following format:

DA

SA

TAG (with VID)

Load(s)

Verification

In recent years, the development of ethernet technology has started to move from local area networks to metropolitan area networks, but the metro ethernet required by the operator requires a larger scale and more flow domains (4K is far from enough) and requires isolation from the customer network (the VLANs of the two cannot be mixed together). In order to realize the expandability of the Ethernet, support a large-capacity Ethernet bearer network and isolate a user network and an operator bearer network, a Q-in-Q scheme and a MAC-in-MAC scheme are proposed by an IEEE standard organization. FIG. 1 is a diagram illustrating a prior art Q-in-Q networking scheme; fig. 2 is a schematic diagram of a MAC-in-MAC networking scheme in the prior art.

Meanwhile, a plurality of bridge components are defined in IEEE802.1, a so-called bridge component is a forwarding component composed of a plurality of ports and a forwarding entity and is responsible for forwarding a data message received from one port to another port, and from the viewpoint of model, a bridge implementation may include one bridge component or integrate a plurality of bridge components.

The customer virtual local area network (C-VLAN) component is a VLAN bridging component in the traditional sense defined by IEEE Std802.1q, and has the main characteristic of being able to recognize and process a customer TAG (C-TAG) in the following format:

type (0x8100)

Priority level

CFI

VID

The operator virtual local area network (S-VLAN) component is a key forwarding component of an operator bridge defined by IEEE P802.1ad, and has the main characteristic of being capable of identifying and processing an operator TAG (S-TAG) without identifying C-TAG at all, wherein the formats of the S-TAG and the C-TAG are very similar, but the assigned types are different. The S-TAG format is as follows:

type (0x88a8)

Priority level

DEI

VID

Since the components, i.e., the bridge component, are used to forward the data packet, for the convenience of description, when viewed from the forwarding path of the data packet, if a port is closer to the user, it is called a user-side port, and if a port is closer to the network core, it is called a network-side port. Some components are symmetrical, all ports are the same, and can be used on both the customer side and the network side, such as C-VLAN components and S-VLAN components, but the two components mentioned below are asymmetrical, with ports dedicated exclusively to the customer side and ports dedicated exclusively to the network side, such as I-components and B-components.

The I component is a key forwarding component of a MAC-in-MAC edge bridge defined by IEEE P802.1ah, and is based on an S-VLAN bridging component, but the ports of the I component are divided into a user side port and a network side (namely, Backbone side) port, an S-Tagged interface or a Transparent (Transparent) interface is provided at the user side, an I component label (I-TAG) is identified and processed at the network side, a virtual instance port is abstracted by utilizing Service instance ID (I-SID) correlation in the I-TAG, EISS (Enhanced Internal Sublayer Service, referred to as IEEE802.1q) Service is provided, a plurality of virtual instance ports are merged downwards to form an ISS port (the last ISS is decomposed into a plurality of EISSs by the I-SID), and a B-SA (Backbone Source Address, B-SA) is configured on the ISS port. The mapping from S-VID to I-SID, i.e. the mapping of service instance, is completed on the I component when the virtual instance port is configured, the insertion/deletion of I-TAG is completed on the virtual port when the data is forwarded, and the MAC-in-MAC encapsulation/decapsulation is completed on the ISS on the backbone side. The typical format of I-TAG is as follows:

type (B)

Priority level

I-SID

C-DA (user destination address)

C-SA (user source address)

The B-component is also based on an S-VLAN bridging component, the user side of which is able to recognize and process I-TAGs, the network side is the same as a normal S-VLAN component, but the MAC address processed by the B-component is the backbone MAC address, so the user side port of the B-component is commonly used to receive the I-component or another B-component.

IEEE802.1 in turn divides the hierarchy of networks from a management and technology perspective, including:

the Customer bridge Network (Customer bridge Network) refers specifically to an ethernet Network constructed based on IEEE Std802.1q, and in IEEE p802.1ad/ah and the present invention, it is regarded as an object to be served by a metro ethernet Network.

The Provider bridge Network (Provider bridge Network) is specifically an operator Network constructed based on IEEE802.1 ad, i.e. Q-in-Q scheme, and is used to provide ethernet service to the user bridge Network, which further expands the ethernet and realizes the isolation of the operator VLAN and the user VLAN.

Backbone bridge networks (Backbone bridge networks) refer in particular to Backbone ethernet networks constructed based on the IEEE802.1 ah, i.e. MAC-in-MAC scheme, which are mainly used for interconnecting multiple operator bridge networks.

The metro ethernet network generally refers to a carrier network constructed by an operator using ethernet technology, and in a narrow sense, refers to an operator carrier network constructed by using the above operator bridge network and backbone bridge network.

The Q-in-Q scheme is characterized in that a layer of VLAN labels are expanded on the basis of the original VLAN, so that the number of flow domains reaches 4 Kx 4K, and an operator network only uses an outer layer VLAN label as a forwarding basis, namely, the VLAN of the operator is established and is called as an operator VLAN (S-VLAN, Service Provider VLAN), so the originally defined VLAN is called as a Customer VLAN (Customer VLAN, C-VLAN), a network based on the C-VLAN is called as a user bridge network, and an operator Ethernet based on the Q-in-Q scheme is called as an operator bridge network.

For C-VLANs, the customer VLAN TAG (C-TAG) in the data message has a customer VLAN ID (C-VID) for distinguishing the customer flow domains, while the S-VLAN uses the operator VLAN ID (S-VID) in the operator VLAN TAG (S-TAG) to distinguish the operator flow domains, and each operator S-VID has a plurality of customer C-VIDs. The message format of adding S-TAG after the user data message is sent to the S-VLAN component is as follows:

C-DA

C-SA

S-TAG (with S-VID)

C-TAG (with C-VID)

Load(s)

Verification

Three user interfaces are defined based on the Q-in-Q scheme:

port-based Service Interface: the port-based service interface, i.e., the S-VLAN component, is a transparent interface to the IEEE Std802.1 d/q. The provider bridge network edge provides services to users on a port basis, and all user data messages from the port (all C-VLANs of the port) are mapped to one S-VLAN configured by the port.

C-Tagged Service Interface: the C-Tagged service interface, the network edge device of the operator bridge can identify the C-TAG, so that even the user data message from the same port can select the service instance according to the C-VID, generally speaking, a plurality of S-VLANs are configured based on the port, several C-VLANs are multiplexed under each S-VLAN, the interface is provided for IEEE Std802.1q by C-VLAN components, but S-VLAN components and C-VLAN components are simultaneously realized in one edge bridge of the operator, from the model, the interface is a double Relay model, the S-VLAN components provide the service interface based on the port for the C-VLAN components in the edge bridge, and then the C-Tagged interfaces are provided for users by the C-VLAN components.

S-Tagged Service Interface: and the S-VLAN component provides an S-Tagged service interface for IEEE P802.ad, the user bridge network edge device can identify the S-VLAN, and the user bridge network submits the data message to the operator bridge network after finishing Q-in-Q packaging.

The simple and easy-to-use Q-in-Q scheme solves the problem of the scalability of the ethernet network to a certain extent, so that the number of users in the ethernet network increases greatly, but because the Q-in-Q scheme does not isolate the user network completely, the operator bridge network has to learn the user MAC address, so that the forwarding data table (FDB) entries to be established by the bridge increase greatly, which becomes a bottleneck for further extending the network scale.

The MAC-in-MAC scheme provides that a layer of MAC Address (Backbone MAC Address) is packaged on the whole Ethernet data message from a user bridge network or an operator bridge network at the edge of a Backbone bearing network to form a Backbone bridge network, a tunneling transmission mechanism is formed, MAC access points are established at the edge of the Backbone bridge network, and the Backbone MAC Address of each edge node drives a plurality of user MAC addresses.

At the core of the Backbone bridge network, the working behavior of the ethernet is similar to that of a common ethernet, including address learning, forwarding behavior, spanning tree and the like, and the Backbone bridge network also has a VLAN called Backbone VLAN (B-VLAN), and the format of a TAG Backbone VLAN TAG (Backbone VLAN TAG, B-TAG) is the same as that of S-TAG. However, at the edge of the backbone bridge network, two functions are to be performed: and finishing the encapsulation and decapsulation of the MAC-in-MAC and performing service instance mapping. Both functions are performed on the I-component. A special Service Instance TAG (I-TAG) is defined in the MAC-in-MAC scheme, the special Service Instance TAG (I-TAG) contains a destination MAC address (Customer DA, C-DA) and a source MAC address (Customer SA, C-SA) of a user data message, the I-TAG also contains a Service Instance identifier (Service Instance ID, I-SID) with the length of 24 bits, and each value represents a Service Instance. The MAC-in-MAC encapsulation format completed by the backbone bridge network edge is as follows:

B-DA

B-SA

B-TAG (with B-VID)

I-TAG(I-SID、C-DA、C-SA)

S-TAG (with S-VID)

C-TAG (with C-VID)

Load(s)

Verification

Three user interfaces are defined based on the MAC-in-MAC scheme:

1, transfer Service Interface: a transparent service interface, i.e. a service interface based on a port, provides services to an operator bridge network or a user bridge network on the basis of the port at the edge of a backbone bridge network, and all data packets from the port are mapped into a service instance (service instance, identified by I-SID) configured for the port. This interface is provided by the I-component in the edge bridge.

S-Tagged Service Interface: the S-Tagged service interface is characterized in that a port at the edge of a backbone bridge network can identify an S-TAG, service instance mapping is carried out based on the S-VID, and two modes are provided according to the description of IEEE P802.1ah: each S-VLAN is mapped to a Service instance and a plurality of S-VLANs are mapped to a Service instance, which is also called S-Tagged Service Bundling Interface. This interface is also provided by the I-component of the edge bridge.

I-Tagged Service Interface: the I-Tagged service interface realizes service instance mapping at the edge of an operator bridge network or a user bridge network, and directly submits a data message to a core backbone network after MAC-in-MAC encapsulation is completed, namely, a component B is realized in an edge bridge, the component I is realized at a user side, and the component B provides an I-Tagged interface for a user.

The MAC-in-MAC scheme has the advantages that for the backbone bridge network, as the transmission and forwarding in the network core only takes the MAC address of a backbone edge MAC access point as a forwarding basis, and the number of edge nodes is not large, the FDB of the backbone Ethernet core is not large, but the scheme is basically positioned at the edge of the backbone bridge network at present, mainly faces to an operator bridge network, although a transparent service interface is also defined and can directly face to a user bridge network to a certain extent, a C-Tagged interface is not defined like the operator bridge, and finer-grained service cannot be provided.

Disclosure of Invention

The invention aims to provide a metro Ethernet edge bridge, which can flexibly provide various service interfaces, and access to a customer bridge network with finer granularity is realized in the MAC-in-MAC metro Ethernet edge bridge, so that the MAC-in-MAC bridge is pushed to a customer edge.

To this end, the invention provides a metro ethernet edge bridge comprising an asymmetric bridge component comprising a user side port, a network side port and a forwarding entity, wherein,

the user side port is used for providing a transparent interface for a user network, supporting a virtual user ID and realizing the association with the service instance of the operator by utilizing the virtual user ID;

a network side port for receiving and sending a data packet, which is encapsulated by the MAC-in-MAC and contains labels of associated operator service instances but does not contain labels of a backbone network, from the backbone Ethernet, supporting a plurality of operator service instances, supporting insertion/deletion of service instance labels, and supporting MAC-in-MAC encapsulation/decapsulation;

and the forwarding entity is used for establishing a forwarding mapping table of the user address, the backbone address, the network bridge port and the operator service instance and forwarding the message.

The user side port of the metro Ethernet edge bridge provided by the invention does not recognize and process the operator network label and the user network label.

The metro ethernet edge bridge provided by the present invention may further comprise a backbone bridge component, wherein the backbone bridge component provides a network side interface and provides the asymmetric bridge component with a label interface of an associated operator service instance, and a user side port of the asymmetric bridge component provides a transparent interface to a user network.

The metro ethernet edge bridge may further comprise at least one operator virtual local area bridge drop component, wherein the operator virtual local area bridge drop component is configured to provide a user side interface, and the asymmetric bridge component is configured to provide a network side interface and internally provide a transparent interface to the operator virtual local area bridge drop component.

The metro ethernet edge bridge may further comprise at least one customer virtual local area bridge drop component, wherein the customer virtual local area bridge drop component is configured to provide a customer side interface, and the asymmetric bridge component is configured to provide a network side interface and internally provide a transparent interface to the customer virtual local area bridge drop component.

The metro ethernet edge bridge may further include at least one operator virtual lan bridge drop component and at least one customer virtual lan bridge drop component, the customer virtual lan bridge drop component is configured to provide a customer-side interface, the asymmetric bridge component is configured to provide a network-side interface, and, inside the bridge, the asymmetric bridge component is configured to provide a transparent interface to the operator virtual lan bridge drop component, and the operator virtual lan bridge drop component is configured to provide a transparent interface to the customer virtual lan bridge drop component.

The asymmetric bridge component in the metro Ethernet edge bridge provided by the invention provides a user side port for a user network while providing transparency for other bridge components in the bridge.

The network side port of the metro Ethernet edge bridge provided by the invention can support a plurality of virtual ports, each virtual port is associated with an operator service instance, each port is configured with a virtual ID, insertion/deletion of a service instance label is supported, and MAC-in-MAC encapsulation/decapsulation is supported.

The invention also discloses a metropolitan area Ethernet system, which comprises a user bridge network and an operator backbone bridge network, and is characterized in that the user bridge network is connected to the operator backbone bridge network through an operator edge bridge network, the operator backbone bridge networks are connected through a backbone network edge bridge network, the operator edge bridge network comprises an asymmetric bridge component, the asymmetric bridge component comprises a user side port, a network side port and a forwarding entity, wherein,

and the forwarding entity is used for establishing a forwarding mapping table of the user MAC address, the backbone MAC address, the network bridge port and the operator service instance and forwarding the message.

The backbone network edge bridge and the operator edge bridge both support an MAC-in-MAC access mode.

The carrier edge bridge includes an asymmetric bridge component including a user-side port, a network-side port, and a forwarding entity, wherein,

The network side port can also support a plurality of virtual ports, each virtual port is associated with an operator service instance, each port is configured with a virtual ID, insertion/deletion of service instance labels is supported, and MAC-in-MAC encapsulation/decapsulation is supported.

The carrier edge bridge further comprises at least one carrier virtual local area bridge drop component, wherein the carrier virtual local area bridge drop component is configured to provide a user-side interface and the asymmetric bridge component is configured to provide a network-side interface and internally provide a transparent interface to the carrier virtual local area bridge drop component.

The carrier edge bridge also includes at least one customer virtual local area bridge drop component, wherein the customer virtual local area bridge drop component is to provide a customer-side interface, and the asymmetric bridge component is to provide a network-side interface and internally provide a transparent interface to the customer virtual local area bridge drop component.

The operator edge bridge further comprises at least one operator virtual local area bridge drop component for providing a user side interface and at least one customer virtual local area bridge drop component for providing a network side interface, and, within the bridge, the asymmetric bridge component for providing a transparent interface to the operator virtual local area bridge drop component for providing a transparent interface to the customer virtual local area bridge drop component.

The invention also discloses a method for providing service at the edge of the metro Ethernet, which comprises the following steps:

the user bridge network is connected to the user side port of the metro Ethernet edge bridge;

establishing a mapping relation table of virtual user ID and operator service based on a user side port of a metropolitan area Ethernet edge network bridge; the mapping relation table is a mapping relation table of a user MAC address, a backbone MAC address, a network bridge port and an operator service instance;

and the metro Ethernet edge bridge identifies the data message and completes service instance mapping or output port mapping according to the mapping relation.

Drawings

FIG. 1 is a diagram illustrating a prior art Q-in-Q networking scheme;

FIG. 2 is a diagram illustrating a MAC-in-MAC networking scheme in the prior art;

FIG. 3a is a schematic diagram of an edge bridge structure constructed based on I' components according to an embodiment of the present invention;

FIG. 3b is a schematic diagram of an edge bridge structure constructed based on I' components and S-VLAN components according to a second embodiment of the present invention;

FIG. 3C is a schematic diagram of an edge bridge structure constructed based on I' components and C-VLAN components according to a third embodiment of the present invention;

FIG. 3d is a schematic diagram of an edge bridge structure constructed based on I' components, S-VLAN components and C-VLAN components according to a fourth embodiment of the present invention;

FIG. 4 is a schematic diagram of an edge bridge structure formed by integrating components B and components C-VLAN based on I' components in a fifth embodiment of the present invention;

fig. 5 is a schematic diagram of a metro ethernet system according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments, which are only used for explaining the present invention and do not represent limitations of the present invention.

The invention provides a bridge component of a metro Ethernet bridge, which is called an I' component in the embodiment, the component is an asymmetric component formed by a forwarding entity and a plurality of ports, and the ports of the component are divided into two types, one type is a user side port, and the other type is a network side port. At the same time the component is not based on S-VLAN bridging parts, i.e. the component does not recognize and process S-TAGs, but I-TAGs.

The user-side ports function as follows:

1. receiving an IEEE802.1 d/q/ad data message sent by a user network, and providing a transparent interface for a user side port connected with the data message;

2. supporting a virtual ID, associating the data messages on all the ports with the virtual ID, and associating the virtual ID with a service instance corresponding to the I-SID;

3. and providing the C-DA, the C-SA and the virtual ID as a forwarding basis for the forwarding entity.

The key features and functions of the network-side ports are as follows:

1. receiving a data message which is packaged by MAC-in-MAC and contains I-TAG from backbone Ethernet;

2. supporting a plurality of I-SIDs and being responsible for inserting and deleting I-TAGs;

3. and configuring a backbone network source address on the port, and performing MAC-in-MAC encapsulation/decapsulation on the data message.

The forwarding entity key features and functions are as follows:

1. establishing a forwarding mapping table of a user address and an operator service instance according to the user MAC address, the I-SID information, the user side port and the network side port information;

2. and according to the user MAC address and the I-SID information, indexing the forwarding mapping table, determining a port, providing message information to an output port, and if the output port is a network side port, simultaneously providing backbone MAC address parameters to the port.

The present invention also provides another ethernet bridging component, referred to as an I "component, that includes a user-side port, a network-side port, and a forwarding entity. Unlike the I 'component, at the network-side port of the I' component, at least one ISS is included, and the ISS supports a plurality of EISS virtual ports, one I-SID associated with each virtual port. Configuring virtual ID on user side port of the assembly, configuring virtual ID on network side virtual port, the configured virtual ID of one or more user side ports must be the same as the virtual ID on a certain virtual port, the user side port provides transparent interface for user, after the data message from user is forwarded, the I-TAG is established according to the associated I-SID of the data message to the virtual port, then entering ISS to execute MAC-in-MAC encapsulation.

Although the I' component and the I "component are different in internal implementation, the external interfaces are the same, and the implemented functions are the same, that is, the user-side port is mapped to one service instance, wherein a plurality of user-side ports can be mapped to the same service instance, and the user-side port is only a transparent interface to IEEE802.1 d/q/ad, which is different from the current IEEE802.1 ah.

Fig. 3a is a schematic diagram of an edge bridge structure constructed based on I' components according to an embodiment of the present invention. As previously mentioned, the I' component is an asymmetric bridge component, with the user-side port being used only to connect to the user bridge network and the network-side port being used only to connect to the carrier network or the carrier backbone bridge network.

In the bridge, the user side port only provides a transparent interface for a user network (comprising IEEE802.1 d/q/ad), each port can be mapped to a service instance associated with one I-SID, but one service instance can correspond to a plurality of ports. And mapping the ports and the service instances is realized by configuring the service instances and the virtual IDs on the user-side ports. And the network side ports complete MAC-in-MAC encapsulation/de-encapsulation and I-TAG insertion/deletion, and each network side port can be associated with a plurality of I-SIDs. The forwarding entity user establishes a user address and a forwarding mapping table of the operator service instance by the MAC address, the I-SID and the backbone MAC address to complete the forwarding of the message.

Fig. 3b is a schematic diagram of an edge bridge structure constructed based on I' components and S-VLAN components according to a second embodiment of the present invention. The bridge is made up of an I 'component and at least one S-VLAN component, where the S-VLAN component provides a user-side port, the I' component provides a network-side port, and the I 'component provides a transparent interface to the S-VLAN component, and currently the S-VLAN based I component defined by IEEE p802.1ah is considered a special case of this case, which functions equivalently to one I' component plus one S-VLAN component, especially when the I-SID is virtualized as a virtual port on the network side.

In the invention, the S-VLAN component only provides a transparent interface for the IEEE802.1 d/q user network as a user side port, each port or a plurality of ports are mapped to an S-VLAN related to an S-VID by configuring PVID on the user port, and then each S-VLAN is mapped to a service instance (which is a special case of the embodiment and is also a case specified by the I component of IEEE P802.1ah) or a plurality of S-VLANs are mapped to a service instance.

Wherein the user-side port provides only an S-Tagged interface to the user network of IEEE p802.1ad, such that it can map different S-VLANs from the user-side port to different service instances. Inside the edge bridge, the I' component provides a transparent interface for the S-VLAN and simultaneously establishes a mapping relation between a user address and an operator service instance, and the forwarding mapping relation of the edge bridge is formed by associating the user MAC address, the I-SID, the S-VID, the backbone MAC address and a port. The network-side ports of the edge bridge perform MAC-in-MAC encapsulation/decapsulation and I-TAG insertion/deletion, and each network-side port may be associated with multiple I-SIDs.

From a model point of view, one I' component and one S-VLAN component can be combined into one S-VLAN based I component described by IEEE802.1 ah, which can be realized by combining two forwarding relation tables and combining port functions.

From the view of the port, the user side port of the I component is provided by the S-VLAN component, the network side port of the I component is the network side port of the I' component, the processing abstraction of the I-SID is an EISS virtual port, the virtual port can be configured with a plurality of S-VIDs, and the mapping relation from the S-VIDs to the I-SID is formed naturally.

Fig. 3C is a schematic diagram of an edge bridge structure constructed based on I' components and C-VLAN components in the third embodiment of the present invention. The edge bridge is comprised of an I ' component and at least one C-VLAN component, the C-VLAN component providing a user-side port, the I ' component providing a network-side port, and the I ' component providing a transparent interface to the C-VLAN component. Wherein,

the user side port provides a transparent interface for the user network of IEEE802.1 d, and realizes that a single port or a plurality of ports are mapped to a C-VLAN associated with C-VID by configuring PVID on the user port, and then each C-VLAN is mapped to a service instance or a plurality of C-VLANs are mapped to a service instance; the user side port provides a C-Tagged interface for the user network of IEEE P802.1q, so that the C-VLAN from the user side port can be mapped to different service instances, namely, the user is accessed in the granularity of the C-VLAN; in the edge bridge, an I' component provides a transparent interface for the C-VLAN and realizes a service instance mapping relation in the transparent interface; the network side ports of the bridge complete MAC-in-MAC encapsulation/decapsulation and I-TAG insertion/deletion, and each network side port can be associated with a plurality of I-SIDs; the mapping relation between the user address of the edge bridge and the service instance of the operator is formed by associating the user MAC address, the I-SID, the C-VID, the backbone MAC address and the port.

In conjunction with the IEEE P802.1ah idea, a special case of the edge bridge of the present invention is to specify an I' component and a C-VLAN combination to form a C-VLAN based I component, and directly establish a mapping relationship from C-VID to I-SID on the component. The edge bridge formed in this way is mainly characterized in that a C-Tagged service interface is provided at the customer side of the bridge, so that the backbone network edge bridge can directly select a service instance according to the C-VID, and further the operator backbone bridge network can directly provide the Ethernet service for the customer bridge network without passing through the operator bridge network based on the Q-in-Q scheme.

As shown in fig. 3C, the C-VLAN based I-component is a C-VLAN forwarding bridge component, whose user-side Port can recognize the C-TAG, whose configured Port VID (Port VID, PVID) is also resolved according to the C-VID, whose backbone-side Port is divided into a number of virtual ports, each virtual Port is associated with an I-SID, each virtual Port is aware of the C-TAG, and whose configured PVID is also resolved according to the C-VID, and the association of the C-VID and the I-SID is performed on the C-VLAN based I-component, specifically, on the virtual Port associated with each I-SID, the belonging C-VLAN is configured.

After the backbone network data message is received by the I component, extracting I-TAG, determining an EISS virtual port according to the I-SID, then using C-VID combined with C-DA to search FDB, and determining an output port, namely a C-Tagged interface.

FIG. 3d is a schematic diagram of an edge bridge structure constructed based on I' components, S-VLAN components and C-VLAN components in the fourth embodiment of the present invention. The edge bridge comprises an I ' component, at least one S-VLAN component and at least one C-VLAN component, wherein the C-VLAN component provides a user side port, the I ' component provides a network side port, the I ' component provides a transparent interface for the S-VLAN component, and the S-VLAN component provides a transparent interface for the C-VLAN. In a particular example, there is an I' component and an S-VLAN component within the bridge, combined into an I component, which is then connected to the customer side C-VLAN component, the I component providing a transparent interface to the C-VLAN component. Wherein,

a user side port based on C-VLAN provides a transparent interface for IEEE802.1 d user network, PVID is configured on the user port to realize mapping from a single port or a plurality of ports to C-VLAN associated with a C-VID, data messages of the user port enter an S-VLAN component after passing through the C-VLAN component, the single or a plurality of C-VLANs are mapped to an S-VLAN, then the data messages enter an I' component, and the single or a plurality of S-VLANs are mapped to a service instance.

The C-VLAN based customer side port provides a C-Tagged interface to the IEEE p802.1q customer network,

this enables mapping of the C-VLAN from the user-side port to different service instances, i.e. accessing the user at the granularity of the C-VLAN.

Inside the edge bridge, the I' component provides a transparent interface to the S-VLAN, the S-VLAN component provides a transparent interface to the C-VLAN component, and the service instance mapping relation is determined by two relays.

The network side ports of the bridge complete MAC-in-MAC encapsulation/decapsulation and I-TAG insertion/deletion, and each network side port may be associated with multiple I-SIDs.

The mapping relation between the customer address of the edge bridge and the service instance of the operator is formed by associating the customer MAC address, the I-SID, the S-VID, the C-VID, the backbone MAC address and the port.

According to the description of IEEE p802.1ah, an I-Tagged interface is typically provided by a B-component to an I-component, i.e., the B-component can be used as a network-side port. Based on the I' component, the invention further provides a bridge comprising a B component. That is, in a bridge containing an I 'component, a B component is inserted on the network side of the I' component, the B component provides a network-side port, and other components capable of providing a user interface serve as user-side ports. Mapping of user addresses to operator service instances may also be implemented.

Fig. 4 is a schematic diagram of an edge bridge structure formed by combining an I' component and a C-VLAN component with a B component according to a fifth embodiment of the present invention. The B component provides a network side port, the C-VLAN component provides a user side port, and in the bridge, the B component provides an I-Tagged interface for the I 'component, the I' component provides a transparent interface for the C-VLAN component, and the C-VLAN component provides a C-Tagged interface or a transparent interface for different user messages.

Although the present invention only shows one embodiment of inserting B-components in I' -component based edge bridges, it should be noted that the insertion of B-components in all edge bridges disclosed in the present invention falls within the scope of the inventive concept.

Referring to fig. 5, the present invention further provides a metro ethernet system including a customer bridge network and an operator backbone bridge network. The user bridge network in the network is connected to the operator backbone bridge network through an operator edge bridge, and the operator backbone bridge networks are connected through backbone network edge bridges. Where the operator edge bridge implements user access and service instance mapping, and then completes the secondary MAC encapsulation on the network-side port of the I' component (or I-component). The operator backbone bridge networks are interconnected through an I-Tagged interface of the backbone network edge bridge.

The metro Ethernet system comprises a user bridge network and an operator backbone bridge network, wherein the user bridge network is connected to the operator backbone bridge network through an operator edge bridge, and the operator backbone bridge networks are connected through a backbone network edge bridge.

And the backbone network edge bridge and the operator edge bridge both support the MAC-in-MAC access mode.

The operator edge bridge comprises an asymmetric bridge component, the asymmetric bridge component comprises a user side port, a network side port and a forwarding entity, wherein the user side port is used for providing a transparent interface for a user network, supporting a virtual user ID and realizing the association with an operator service instance by utilizing the virtual user ID; a network side port for receiving and sending a data packet, which is encapsulated by the MAC-in-MAC and contains labels of associated operator service instances but does not contain labels of a backbone network, from the backbone Ethernet, supporting a plurality of operator service instances, supporting insertion/deletion of service instance labels, and supporting MAC-in-MAC encapsulation/decapsulation; or the data message is used for receiving and sending the MAC-in-MAC encapsulated data message which contains the label of the associated operator service instance but does not contain the label of the backbone network from the backbone Ethernet, a plurality of virtual ports are supported on the network side, each virtual port is associated with one operator service instance, each port is configured with a virtual ID, the insertion/deletion of the label of the service instance is supported, and the MAC-in-MAC encapsulation/decapsulation is supported; and the forwarding entity is used for establishing a forwarding mapping table of the user address, the backbone address, the network bridge port and the operator service instance and forwarding the message.

And the operator edge bridge further comprises at least one operator virtual local area bridge drop component, wherein the operator virtual local area bridge drop component is to provide a user-side interface, and the asymmetric bridge component is to provide a network-side interface and internally provide a transparent interface to the operator virtual local area bridge drop component.

The operator edge bridge of the present invention further comprises at least one customer virtual local area bridge drop component, wherein the customer virtual local area bridge drop component is configured to provide a customer-side interface, and the asymmetric bridge component is configured to provide a network-side interface and internally provide a transparent interface to the customer virtual local area bridge drop component.

The operator edge bridge of the present invention further comprises at least one operator virtual lan bridge interface component and at least one user virtual lan bridge interface component, wherein the user virtual lan bridge interface component is used to provide a user side interface, the asymmetric bridge component is used to provide a network side interface, and, inside the bridge, the asymmetric bridge component is used to provide a transparent interface to the operator virtual lan bridge interface component, and the operator virtual lan bridge interface component is used to provide a transparent interface to the user virtual lan bridge interface component.

The present invention also proposes a method for providing service at the edge of the metro ethernet network based on the metro ethernet system shown in fig. 5, which comprises:

establishing a mapping relation table of virtual user ID and operator service based on a user side port of a metropolitan area Ethernet edge network bridge;

In short, the bridge, the system and the method provided by the invention can be provided with various interfaces at the edge of the metro Ethernet, can directly provide Ethernet service for the user bridge network, better realize the isolation between the operator network and the user network, reduce the network hierarchy, realize the user access with finer granularity, and simultaneously complete the MAC-in-MAC encapsulation/decapsulation, thereby promoting the development of the MAC-in-MAC backbone core network, and leading the operator bridge network positioned at the user access level and the backbone Ethernet positioned at the core network level to be developed in a balanced way.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A metro Ethernet edge bridge comprising an asymmetric bridge component comprising a user side port, a network side port and a forwarding entity, wherein,

2. The metro ethernet edge bridge of claim 1, wherein said customer side port does not recognize and process operator network tags and customer network tags.

3. The bridge of claim 2, further comprising a backbone bridge component, wherein the backbone bridge component provides a network-side interface and provides the asymmetric bridge component with a label interface for an associated carrier service instance, and wherein a user-side port of the asymmetric bridge component provides a transparent interface to a user network.

4. The metro ethernet edge bridge according to claim 2, wherein said bridge further comprises at least one operator virtual local area bridge drop component, wherein said operator virtual local area bridge drop component is configured to provide a user side interface and said asymmetric bridge component is configured to provide a network side interface and internally provide a transparent interface to said operator virtual local area bridge drop component.

5. The metro ethernet edge bridge according to claim 2, wherein said bridge further comprises at least one customer virtual local area bridge drop component, wherein said customer virtual local area bridge drop component is adapted to provide a customer side interface and said asymmetric bridge component is adapted to provide a network side interface and internally provide a transparent interface to said customer virtual local area bridge drop component.

6. The metro ethernet edge bridge according to claim 2, wherein said bridge further comprises at least one operator virtual local area bridge drop component for providing a customer side interface and at least one customer virtual local area bridge drop component for providing a network side interface, and wherein within said bridge said asymmetric bridge component is for providing a transparent interface to said operator virtual local area bridge drop component for providing a transparent interface to said customer virtual local area bridge drop component.

7. The metro ethernet edge bridge according to any one of claims 3 to 6, wherein said asymmetric bridge component further provides a customer side port to a customer network.

8. The metro ethernet edge bridge of claim 1, wherein the network-side port supports a plurality of virtual ports, each virtual port being associated with an operator service instance, each port being configured with a virtual ID, supporting insertion/deletion of service instance labels, and supporting MAC-in-MAC encapsulation/decapsulation.

9. A metro Ethernet system comprising a customer bridge network and an operator backbone bridge network, characterized in that said customer bridge network is connected to said operator backbone bridge network by an operator edge bridge network, said operator backbone bridge networks are connected by a backbone edge bridge network, said operator edge bridge comprises an asymmetric bridge element comprising a customer side port, a network side port and a forwarding entity, wherein,

10. The ethernet system of claim 9 wherein both the backbone edge bridge and the operator edge bridge support MAC-in-MAC access.

11. The ethernet system as recited in claim 9 or 10, wherein the operator edge bridge further comprises at least one operator virtual local area bridge interface component, wherein the operator virtual local area bridge interface component is to provide a user side interface, and wherein the asymmetric bridge component is to provide a network side interface and internally provide a transparent interface to the operator virtual local area bridge interface component.

12. The ethernet system as recited in claim 9 or 10, wherein the carrier edge bridge further comprises at least one customer virtual local area bridge component, wherein the customer virtual local area bridge component is to provide a customer side interface, and wherein the asymmetric bridge component is to provide a network side interface and internally provide a transparent interface to the customer virtual local area bridge component.

13. The ethernet system as recited in claim 9 or 10, wherein the operator edge bridge further comprises at least one operator virtual local area bridge drop component for providing a user side interface and at least one customer virtual local area bridge drop component for providing a network side interface, and wherein, within the bridge, the asymmetric bridge component is for providing a transparent interface to the operator virtual local area bridge drop component for providing a transparent interface to the customer virtual local area bridge drop component.

14. The ethernet system of claim 9 or 10, wherein said network-side port supports a plurality of virtual ports, each virtual port associated with an operator service instance, each port configured with a virtual ID, supports insertion/deletion of service instance labels, and supports MAC-in-MAC encapsulation/decapsulation.

15. A method of providing service at a metro ethernet edge comprising:

and the metro Ethernet edge bridge identifies the data message and completes service instance mapping or output port mapping according to the mapping relation in the mapping relation table.