WO2007079665A1

WO2007079665A1 - Method and apparatus for supporting vlan stacking in optical network

Info

Publication number: WO2007079665A1
Application number: PCT/CN2007/000021
Authority: WO
Inventors: Lehong Niu
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-01-06
Filing date: 2007-01-05
Publication date: 2007-07-19
Also published as: CN100591039C; CN1996937A

Abstract

A method for supporting VLAN stacking in PON relates to the optical network, resolves the problem that there is no PON standard in the prior art to realize VLAN stacking. The method includes: first, configuring the VLAN stacking attribute of at least one user side port in ONT; then the ONT adds an external layer VLAN mark and internal layer VLAN mark to the data packet without the VLAN mark which is input from the port configured the VLAN stacking attribute. An ONT for supporting VLAN stacking is proposed. The optical system can have the ability to add two layer VLAN marks, and the amount of the VLAN can be enlarged.

Description

Method and apparatus for supporting virtual local area network stacking in an optical network system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to optical network data transmission techniques, and more particularly to a method and apparatus for supporting virtual local area network stacking in an optical network system. BACKGROUND OF THE INVENTION Current mainstream technologies for broadband access are mainly divided into copper access technologies and optical access technologies. Typical representatives of copper wire access technologies include various digital subscriber line (DSL) technologies. The access network implemented by the optical access technology is called the Optical Access Network (OAN).

One common technique for implementing an optical access network is the Passive Optical Network (PON), which is a point-to-multipoint optical access technology. The PON system consists of an optical line terminal (OLT), an optical distribution network (ODN), and an optical network unit (ONU). The OLT provides a network side interface (SNI) for the OAN, which is connected to one or more ODNs; the ODN is mainly a passive optical splitting device, and the function is to transmit the downlink data of the OLT to each ONU through the optical branch, or to the OU. The uplink data is transmitted to the OLT through aggregation; the ONU provides a user-side interface (UNI) for the OAN. If the ONU provides a user port function, such as an Ethernet port or a plain old telephone service port (POTS), such an ONU is called an optical network terminal. (ONT), unless otherwise specified, ONU and ONT are collectively referred to as ONT.

In the general PON access technology, the downstream traffic of the OLT is broadcasted to the ONT through time division multiplexing (TDM), and each ONT receives the required traffic as needed; the upstream traffic of the ONT is controlled by the OLT, and only specific ones are allowed at the same time. The ONT sends the data and then transmits it to the OLT via Time Division Multiple Access (TDMA).

The Gigabit Passive Optical Network (GPON) technology standard is the latest PON technology standard and is defined in the International Telecommunication Union (ITU-T) G984. G984.2. G984.3, G984.4 series of standards. In the GPON standard, the OLT manages the ONT through the OU Management Control Interface (OMCI) channel. OMCI is a match defined in the GPON standard. The transmission channel is established between the OLT and the ONT and is established by the ONT when registering with the OLT. OMCI is a master-slave management protocol, the OLT is the master device, the ONT is the slave device, and the OLT controls the multiple ONTs connected below through the OMCI channel.

In the OMCI protocol, various data of the OLT management ONT are abstracted into a protocol independent management information base (MIB), and the basic information unit of the MIB is a management entity (ME). According to the functional configuration of the ONT, OMCI defines various management entities that the OLT controls the ONT. The ONT implements the configuration management functions of each management entity under the control of the OLT.

In order to isolate traffic between users, each user needs to be divided into different virtual local area networks (VLANs).

Figure 1 is a schematic diagram of the ONT adding a VLAN tag to an Ethernet packet from a user Ethernet port. As shown in FIG. 1, first, in step 100, the ONT receives an Ethernet packet without a VLAN tag from a user Ethernet port; subsequently, in step 102, the medium access control (MAC) bridge module in the ONT is a client. A VLAN tag (VLAN tag) is added to the Ethernet packet sent by the device (CPE), and then sent to the GPON protocol processing module through the internal Ethernet port. Finally, in step 104, the GPON protocol processing module is the received Ethernet. The message adds the necessary optical network protocol header information, and then sends the generated GPON frame to the OLT.

Figure 2 is a schematic diagram of the structure of an Ethernet packet after a VLAN tag is added. The added VLAN tag contains a tag protocol identifier (TPID) and tag control information (TCI). The value of the TPID is fixed to 0x8100. The TCI further includes three parts: 802.1P priority information, Specification Format Information (CFI), and VLAN ID (VLAN ID). The length of the VLAN ID is 12 bits, so a total of 2 ¹² = 4096 different VLANs can be identified. It is defined as the VLAN tag operation configuration data. Each VLAN tag operation configuration data instance corresponds to one ONT Ethernet physical port, and the Ethernet physical port is managed by another management entity Ethernet UM physical path termination point. The attributes of the VLAN tag operation configuration data include:

- Management entity identification: This attribute provides a unique number identifier for each instance of this managed entity. This number identifies the number of the Ethernet UNT physical path endpoint management entity.

- Upstream VLAN tag operation mode:

0x00: Do not add a VLAN tag, regardless of whether there is a VLAN tag in the Ethernet frame;

0x01: Add a VLAN tag. If the Ethernet frame does not have a VLAN tag, add a VLAN tag according to the "upstream VLAN tag TCI value. If the Ethernet frame carries a VLA tag, according to the "upstream VLAN tag TCI value, replace the VLAN tag. TCI value;

0x02 Add a VLAN tag. If the Ethernet frame carries a VLAN tag, add a Layer 2 VLAN tag according to the "upstream VLAN Tag TCI value, if the Ethernet frame does not carry

VLAN tag, add a layer of VLAN tag according to the "upstream VLAN Tag TCI value";

——Upstream VLAN Tag TCI value:

This field is applied when the uplink VLAN tag operation mode is 0x01 and 0x02.

- - Downstream VLAN Tag operation mode:

0x00: No action is taken;

0x01 : Remove the Ethernet frame VLAN tag.

The continuous maturity of network applications has led to a rapid increase in the number of access users. According to the access mode of one VLAN per user, 4096 VLANs have long been unable to meet the needs of users. VLAN stacking technology is generated in this context. The way to expand the number of VLANs is to add two layers of VLAN tags to Ethernet packets. Thus, the number of VLANs that VLAN tags can identify can be extended to 4096 x 4096 « 1.68 x 10 ⁷ pieces.

Although the VLAN stacking technology solves the problem of insufficient number of VLANs,

The description of the VLAN tag operation configuration data shows that the VLAN tag operation configuration data does not define how to implement VLAN stacking for the ONT. The current GPON standard does not define any management entity for implementing VLAN stacking. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for supporting VLAN stacking in an optical network system, which can enable an optical network system to have the capability of adding two layers of VLAN tags to an Ethernet frame. The method comprises the following steps:

The VLAN stacking attribute is configured on the at least one user-side port of the optical network terminal. The optical network terminal adds an outer VLAN tag and an inner VLAN tag to the data packet that is not included in the VLAN tag input by the port configured with the VLAN stacking attribute.

Another object of the present invention is to provide an optical network terminal supporting VLAN stacking, which has the capability of adding two layers of VLAN tags to an Ethernet frame. In addition to the passive optical network protocol processing module and the medium access control MAC bridge, the optical network terminal further includes:

The stack attribute configuration module is configured to save stack attribute information.

The stack processing module is configured to add an outer VLAN tag and an inner VLAN tag to the VLAN-free tag of the user-side Ethernet port of the optical network terminal according to the stack attribute information saved by the stack attribute configuration module.

The stack attribute information includes a VLAN stack flag bit, an outer VLAN tag, and an inner VLAN tag.

The invention has the beneficial effects that the optical network system has the capability of adding two layers of VLAN tags to the Ethernet frame by implementing the method for supporting VLAN stacking in the optical network system, and greatly expands the number of VLANs. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be further described with reference to the accompanying drawings and embodiments. FIG. 1 is a schematic diagram of an ONT adding VLAN information to an Ethernet packet from a user Ethernet port.

Figure 2 shows the structure of an Ethernet packet after a VLAN tag is added.

FIG. 3 is a configuration management system for configuring an ONT port through an OLT according to an embodiment of the present invention; Flowchart for VLA stacking properties.

Figure 4 is a schematic diagram of adding a Layer 2 VLAN tag to an Ethernet packet from a user-side port configured with VLAN stack attributes.

Figure 5 is a flow chart showing the processing of a packet from a user-side port that does not include a VLAN tag by the ONT according to an embodiment of the present invention.

FIG. 6 is a schematic structural diagram of an Ethernet packet after adding a two-layer VLAN tag; FIG. 7 is a schematic diagram of an internal structure of an ONT according to an embodiment of the present invention. The core content of the embodiment of the present invention is as follows: The VLAN stacking attribute is configured for the user-side port of the ONT, and the ONT saves the configured VLAN stacking attribute; the ONT is configured according to the configured VLAN stacking attribute, and is from the user-side port. The data packet encapsulates two layers of VLAN tags.

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the present invention will be further described in detail below with reference to the embodiments.

Figure 3 is a flow chart of configuring the management system to configure the VLAN stacking attribute on the user side port of the ONT through the OLT, including the following steps:

Step 300: The configuration management system sends a VLAN stack configuration command to the OLT, where the configuration parameters include: an ONT identifier, a port number of the VLAN stack attribute port, an outer VLAN tag, and an inner VLAN tag. Step 302: The OLT passes the OMCI channel. Sends the OMCI message of the stacking attribute of the VLAN of the ONT port. The configuration parameters include: the ONT identifier, the port number of the VLAN stack attribute port, the outer VLAN tag, and the inner VLAN tag.

Step 304: The ONT stores the received VLAN stack attributes, including an outer VLAN tag, an inner VLAN tag, and a corresponding port number.

Step 306: The ONT returns a configuration response message to the OLT. In addition, those skilled in the art understand that the configuration of the VLAN stacking attribute is not limited to configuring the ONT through the OMCI channel, and other methods for configuring the ONT are also effective, including configuring the ONT through the TR069 protocol. Configure the ONT directly or remotely. After the configuration is complete, the ONT saves the parameters configured for the port in the VLAN stack management entity.

Figure 4 is a schematic diagram of the ONT adding a Layer 2 VLAN tag to an Ethernet packet from a user-side port configured with the VLAN stack attribute, including the following steps:

Step 400: The ONT receives an Ethernet packet without a VLAN label from the user-side Ethernet port.

Step 402: The MAC bridge module in the ONT adds two layers of VLAN tags to the Ethernet packets sent by the CPE, and then sends them to the GPON protocol processing module through the internal Ethernet port. Step 404: The GPON protocol processing module is the received Ethernet. The message adds the necessary optical network protocol header information, and then sends the generated GPON frame to the OLT.

If the packet is from a user-side port that is not configured with the VLAN stacking attribute, the VLAN tag is added to the packet according to the process of the prior art. If the packet from the user-side port already carries the VLAN tag, the process is also performed according to the prior art. Add a VLAN tag to the packet.

In order to make the above process clearer, the following is a detailed description in the form of a flow. FIG. 5 is a flowchart of processing, by the ONT, a data packet from a user-side port that does not include a VLAN tag according to an embodiment of the present invention, including the following steps:

Step 500: The ONT receives the Ethernet packet that does not contain the VLAN tag through the user port. Step 502: The ONT searches for the VLAN stack management entity, and checks whether the port is configured with the VLAN stacking attribute. If the port is configured with the VLAN stacking attribute, Go to step 504, otherwise go to step 506;

Step 504: The ONT adds an outer VLAN tag and an inner VLAN tag to the data packet. Step 506: Forward the data packet to the GPON protocol processing module.

The function of the GPON protocol processing module is to add an optical network protocol header to the Ethernet packet, and then send the generated GPON frame to the OLT. Figure 6 is a schematic diagram of the structure of an Ethernet packet after adding two layers of VLAN tags. The content of the inner VLAN tag is the same as that defined in the single-layer VLAN tag defined in Figure 2. The outer VLAN tag also contains the TPID and TCI parts. Here the value of TPID is 0x88a8. The TCI further includes three parts: 802. IP priority information, drop compliance indication information (DEI), and VLAN ID, where the length of the VLAN ID is 12 bits.

The VLAN stack management entity may be a VLAN tag operation that adds a VLAN stack flag (value 0x03) and an inner VLAN tag to an inner VLAN tag TCI value. The modified VLAN tag operation configuration data structure is as follows: :

- Management entity identification:

This attribute provides a unique number identifier for each instance of this managed entity. This number identifies the same number as the Ethernet U T physical path endpoint management entity.

- Upstream VLAN tag operation mode:

0x01: Add a VLAN tag. If the Ethernet frame does not have a VLAN tag, add the VLA tag according to the "upstream VLAN tag TCI value. If the Ethernet frame has a VLAN tag, replace the VLAN tag with the "upstream VLAN tag TCI value". TCI value;

0x02 Add a VLAN tag. If the Ethernet frame has a VLAN tag, add a Layer 2 VLAN tag according to the "upstream VLAN Tag TCI value. If the Ethernet frame does not have a VLAN tag, add a VLAN according to the "upstream VLAN Tag TCI value". label;

0x03 (VLAN stack flag): Add a VLAN tag. If the Ethernet frame does not have a VLAN tag, add the outer VLAN tag according to the "upstream VLAN tag TCI value. Add the inner layer according to the "uplink inner VLAN tag TCI value." VLAN tag;

——Upstream VLAN Tag TCI value:

When the uplink VLAN tag operation mode is 0x01, 0x02, or 0x03, apply the Field

- Upstream Inner VLAN Tag TCI value:

This field is applied when the uplink VLAN tag operation mode is 0x03. - Downstream VLAN Tag operation mode:

0x00: No action is taken;

0x01: Remove the Ethernet frame VLAN tag.

In addition to modifying the VLAN tag operation configuration data of an existing management entity, you can also define a separate VLAN stack management entity, including the VLAN stack flag, the outer VLAN tag, and the inner VLAN tag.

The internal structure of the ONT of the embodiment of the present invention is as shown in FIG. 7, and includes the following parts:

The GPON protocol processing module 701 implements the GPON protocol stack function; the MAC bridge 702 implements the Ethernet bridge function, and both modules are existing modules;

The stacking and stacking module 703 is configured to determine whether the received Ethernet packet meets the following conditions simultaneously according to the stack attribute configuration information stored in the stack attribute configuration module 704: a. From the user side configured with the VLAN stacking attribute An Ethernet port; b, no VLAN tag; the inner VLAN tag and the outer VLAN tag are added to the packet according to the judgment result; the stack attribute configuration module 704 is configured to store the configuration information of the stack attribute, including the inner layer stack. The processing module 703 and the stack attribute configuration module 704 can be used as separate modules, or can be combined into one module, or as a sub-module inside the MAC bridge 702 or the GPON protocol processing module 701.

The above is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or within the technical scope disclosed by the present invention. Alternatives are intended to be covered by the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

Claim

A method for supporting VLAN stacking of a virtual local area network in an optical network system, characterized in that the method comprises the following steps:

The VLAN stacking attribute is configured on the at least one user-side port of the optical network terminal. The optical network terminal adds an outer VLAN tag and an inner VLAN tag to the data packet that does not include the VLA label input by the port configured with the VLAN stacking attribute.

The method according to claim 1, wherein the manner in which the VLAN stacking attribute is configured on at least one port of the optical network terminal comprises:

Configuring the optical network terminal by using an optical network terminal management control interface; or configuring the optical network terminal by using a TR069 protocol;

The optical network terminal is configured by a configuration management system direct connection or remote control.

The method according to claim 2, wherein, when the optical network terminal is configured by the optical network terminal management control interface, at least one user-side port configuration of the optical network terminal is configured. VLAN stacking attributes include:

Sending, by the configuration management interface, a VLAN stack configuration command to the optical line terminal, where the VLAN stack configuration command includes the outer VLAN tag and the inner VLAN tag;

The optical line terminal configures the VLAN stack attribute for the at least one port in the optical network terminal by using an optical network terminal management control interface channel according to the VLAN stack configuration command, and the configuration parameter includes the outer VLAN tag. The inner VLAN tag and the corresponding port number.

The method of claim 1, wherein the optical network terminal adds an outer VLAN tag and an inner VLAN tag to a data packet that does not include a VLAN tag and is input to a port configured with a VLAN stacking attribute, including:

The optical network terminal determines whether the data packet received by the port configured with the VLAN stacking attribute includes a VLAN tag, and if yes, processes the data packet according to the prior art, otherwise Follow-up steps;

The optical network terminal adds an outer VLA label and an inner VLAN tag in the port VLAN stacking attribute to the data packet.

The method according to claim 1, wherein the optical network terminal adds an outer VLAN tag and an inner VLAN tag to a data packet that does not include a VLAN tag, which is input by a port configured with a VLAN stacking attribute. And further comprising: the optical network terminal adding an optical network protocol header to the data packet to which the outer VLAN tag and the inner layer VLAN tag are added, and sending the optical network protocol header to the optical line terminal.

An optical network terminal supporting a VLAN stack, comprising a passive optical network protocol processing module and a medium access control MAC bridge, wherein the optical network terminal comprises: a stack attribute configuration module, configured to save stack attribute information ;

The stack processing module is configured to add an outer VLAN tag and an inner VLAN tag to the VLAN-free label of the user-side Ethernet port of the optical network terminal according to the stack attribute information saved by the stack attribute configuration module.

The optical network terminal according to claim 6, wherein the stack attribute information includes a VLAN stack flag bit, an outer VLAN tag, and an inner VLAN tag.