CN112118493B

CN112118493B - Method and system for realizing multicast protocol in ERPS looped network

Info

Publication number: CN112118493B
Application number: CN202010856650.1A
Authority: CN
Inventors: 杨冬
Original assignee: Fiberhome Telecommunication Technologies Co Ltd
Current assignee: Fiberhome Telecommunication Technologies Co Ltd
Priority date: 2020-08-24
Filing date: 2020-08-24
Publication date: 2022-02-18
Anticipated expiration: 2040-08-24
Also published as: CN112118493A

Abstract

The invention discloses a method for realizing multicast protocol in ERPS ring network, which comprises the following steps: dividing all nodes OLT in ERPS ring network into two types, dividing the equipment connected with multicast server or exchanger into multicast edge nodes, and dividing other nodes into non-multicast edge nodes; a port connected with the multicast edge node and the multicast server or the switch is forcibly configured as a multicast uplink port, and the port can only enter a multicast data stream and cannot forward the multicast data stream; all the initial ports of the non-multicast edge node are invalid ports; and the ports on the multicast edge node and the non-multicast edge node are configured as a multicast uplink port, a multicast cascade port or an invalid port. When the invention runs the multicast protocol on the ERPS ring network, under the condition that the ERPS link fails and the forwarding direction of the multicast data stream changes, all ERPS node ports are quickly and dynamically determined to be recovered to multicast uplink ports or multicast cascade ports. The invention also provides a corresponding system for realizing the multicast protocol in the ERPS ring network.

Description

Method and system for realizing multicast protocol in ERPS looped network

Technical Field

The present invention belongs to the field of communication technology, and more particularly, to a method and system for implementing a multicast protocol in an ERPS ring network.

Background

With the popularization of large modules of PON (Passive Optical Network) access devices, the problems of insufficient Optical cables and service Protection are increasingly highlighted, and to solve these problems, MSTP (Multiple Spanning Tree Protocol) and ERPS (Ethernet Ring Protection Switching) Ring Network protocols are widely applied, but ERPS has advantages of fast convergence, easy expansion, and the like, and is more widely used compared with MSTP.

In the application of the ERPS ring network, if IPTV (Interactive television) service needs to be deployed, the determination of the multicast port roles of all nodes on the ERPS ring network is a difficult point, because the ERPS protocol does not have port roles such as root port, designated port and the like in the MSTP protocol, for example, the root port role determined by the protocols corresponds to the multicast port role as a multicast uplink port, and the designated port role corresponds to the multicast port role as a multicast cascade port; the ERPS protocol only informs all nodes on a loop that link faults occur, but does not inform the change situation of the specific data flow direction, and if link switching occurs in the ERPS ring network, the multicast port roles of all nodes are difficult to be determined quickly and dynamically. The multicast port roles in the invention refer to a multicast uplink port, a multicast cascade port and an invalid port.

Disclosure of Invention

The invention provides a scheme for realizing a multicast protocol in an ERPS ring network, which can rapidly and dynamically determine whether all ERPS node ports are recovered to a multicast uplink port or a multicast cascade port under the conditions that an ERPS link fails and the forwarding direction of a multicast data stream changes when the multicast protocol is operated on the ERPS ring network, and the multicast service can be rapidly recovered after the role of the multicast port is determined.

To achieve the above object, according to an aspect of the present invention, there is provided a method for implementing a multicast protocol in an ERPS ring network, including:

dividing all nodes OLT in ERPS ring network into two types, dividing the equipment connected with multicast server or exchanger into multicast edge nodes, and dividing other nodes into non-multicast edge nodes;

a port connected with the multicast edge node and the multicast server or the switch is forcibly configured as a multicast uplink port, and the port can only enter a multicast data stream and cannot forward the multicast data stream; all the initial ports of the non-multicast edge node are invalid ports;

the ports on the multicast edge node and the non-multicast edge node are configured as a multicast uplink port, a multicast cascade port or an invalid port, wherein:

the multicast uplink port can receive multicast data stream and can receive multicast general group query message, after receiving the multicast general group query message, the OLT can forward all the current multicast address conditions from the port in a message adding mode; the multicast cascade interface can receive the multicast adding message and the multicast leaving message, if the corresponding multicast forwarding table exists, the multicast data stream can be forwarded to the port; the invalid port can neither receive the data stream nor any multicast protocol messages.

In an embodiment of the present invention, when a link of a node OLT in an ERPS ring network fails or a port state changes, an ERPS protocol module on the OLT notifies a multicast module after processing a flow of the protocol and setting a corresponding port as block or forwarding; if the node is a multicast edge node, a port connected with the multicast server is configured as a multicast uplink port, the multicast module inquires the port forwarding state of the multicast uplink port after being notified, and if the port is in a block state, other ports of the multicast edge node are set as the multicast uplink ports; if the port is in forwarding state, setting other ports of the multicast edge node as multicast cascade ports.

In an embodiment of the present invention, after determining the roles of all ports, the multicast edge node forwards a multicast general group query packet to all multicast cascade interfaces under the node.

In one embodiment of the invention, if a certain port of a non-multicast edge node receives a multicast general group query message, an invalid port is modified into a multicast uplink port, and other remaining ports are modified into multicast cascade ports; after the port roles of the non-multicast edge nodes are determined, the multicast general group query message is forwarded to all multicast cascade interfaces and then is transmitted to the next non-multicast edge node, and the multicast roles of all ports on the next node can be determined according to the same principle.

In an embodiment of the present invention, the structure of the multicast forwarding table is:

the added messages from the slot ports are grouped and adopted: the multicast address + the multicast VLAN + the local OLT slot number;

the joining message from the multicast cascade interface is grouped and adopted: the multicast address + the multicast VLAN + a multicast cascade interface of the OLT.

According to another aspect of the present invention, there is provided a system for implementing a multicast protocol in an ERPS ring network, including a multicast edge node and a non-multicast edge node, wherein:

the multicast edge node refers to a device connected with a multicast server or a switch in the ERPS ring network, a port connected with the multicast server or the switch is forcibly configured as a multicast uplink port, and the port can only access multicast data stream and cannot forward the multicast data stream; the non-multicast edge node refers to other nodes in the ERPS ring network, and all initial ports of the non-multicast edge node are invalid ports;

In an embodiment of the present invention, when a link of a node OLT in an ERPS ring network fails or a port state changes, an ERPS protocol module on the OLT notifies a multicast module after processing a flow of the protocol and setting a corresponding port as block or forwarding;

if the node is a multicast edge node, a port connected with the multicast server is configured as a multicast uplink port, the multicast module inquires the port forwarding state of the multicast uplink port after being notified, and if the port is in a block state, other ports of the multicast edge node are set as the multicast uplink ports; if the port is in forwarding state, setting other ports of the multicast edge node as multicast cascade ports.

In one embodiment of the invention, if a certain port of a non-multicast edge node receives a multicast general group query message, an invalid port is modified into a multicast uplink port, and other remaining ports are modified into multicast cascade ports;

after the port roles of the non-multicast edge nodes are determined, the multicast general group query message is forwarded to all multicast cascade interfaces and then is transmitted to the next non-multicast edge node, and the multicast roles of all ports on the next node can be determined according to the same principle.

Generally, compared with the prior art, the technical scheme of the invention has the following beneficial effects:

(1) under the condition of not carrying out protocol extension, the problem that the port multicast role of the node in the ERPS ring network can not be dynamically determined is solved;

(2) after the port multicast role in the ERPS ring network is determined, the multicast uplink port can be set to only receive the multicast general group query message, and the multicast cascade port only receives the multicast join and leave messages, so that the messages of a CPU on the OLT are reduced;

(3) the network expansion configuration is simple, and the ports on the newly added nodes only need to be initially configured as invalid ports.

Drawings

FIG. 1 is a multicast application networking diagram in an ERPS ring network according to the present invention;

fig. 2 is a flowchart illustrating multicast port role recovery of a multicast edge node when a link failure occurs in the embodiment of the present invention;

fig. 3 is a flowchart illustrating a role recovery process of a multicast port of a non-multicast edge node when a link failure occurs according to an embodiment of the present invention;

fig. 4 is a recovery diagram of an ERPS ring network multicast service when a link failure occurs in the embodiment of the present invention;

fig. 5 is a sequence diagram for opening an ERPS ring network multicast service in the embodiment of the present invention;

fig. 6 is a service recovery diagram during extension of an ERPS node in the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The invention provides a method for realizing multicast protocol in ERPS ring network, firstly dividing all nodes in ERPS ring network into two types, dividing the device connected with multicast server or exchanger into multicast edge nodes, and dividing other nodes into non-multicast edge nodes.

A port connected with the multicast edge node and the multicast server or the switch is forcibly configured as a multicast uplink port, and the port can only enter a multicast data stream and cannot forward the multicast data stream;

the non-multicast edge nodes initially all ports are invalid ports.

When a link of a node device on the ERPS ring network fails or a port state changes, the ERPS protocol module notifies the multicast module after processing the flow of the protocol and setting the corresponding port to be block or forwarding. If the node is a multicast edge node device, because a port connected with a multicast server or a switch can be forcibly configured as a multicast uplink port, the port can only access multicast data stream and cannot forward the multicast data stream, a multicast module can inquire the port forwarding state of the configured multicast uplink port after being notified, and if the port is in a block state, other ports of the multicast edge node are set as the multicast uplink ports; if the port is in forwarding state, setting other ports of the multicast edge node as multicast cascade ports. After determining the roles of all the ports, the multicast edge node forwards a multicast general group query message to all the multicast cascade ports under the node.

All the initial ports of the non-multicast edge node are invalid ports, if a certain port receives the multicast general group inquiry message, the invalid port is modified into a multicast uplink port, and meanwhile, the rest other ports are modified into multicast cascade ports. After the port roles of the non-multicast edge nodes are determined, the multicast general group query message is forwarded to all the multicast cascade interfaces and then is transmitted to the next non-multicast edge node, and the multicast roles of all the ports on the next node can be determined according to the same principle.

After the multicast roles of the ports of all the nodes are determined, all the IPTV services under the nodes are recovered.

The node equipment in the invention is OLT, and the OLT is provided with an ERPS protocol module and a multicast module.

Firstly, a certain multicast scene in the ERPS ring network which normally runs is described. An ERPS is a link layer protocol applied to an ethernet ring, and in an ERPS ring network, there are two port forwarding states in which an ERPS protocol is enabled, one is a forwarding state, a port in this state can both forward a data stream and receive/forward an ERPS protocol packet, and the other is a block state, and a port in this state does not forward a traffic but can receive/forward an ERPS protocol packet. In an ERPS loop, the ERPS protocol sets a port to be in a block state to ensure that a broadcast storm caused by a data loop cannot occur in an Ethernet loop; if a working link on the Ethernet ring is in failure, the ERPS protocol can quickly open a backup link to recover the data communication and forwarding among all nodes on the ring network. In the invention, port forwarding states of the ERPS protocol are named forwarding and block, but different vendors may have different names, for example, the vendors are named forwarding and discarding. Therefore, in the present invention, the naming of the port forwarding state does not limit the protection scope of the scheme.

Because the realization mechanism of the multicast service and the message interaction are specific, the port on the OLT for running multicast is divided into three types of ports, one is a multicast uplink port, the port of the role can receive multicast data stream and can receive multicast general group inquiry message, after receiving the multicast general group inquiry message, the OLT can forward all the current multicast address conditions from the port in a message adding mode; secondly, a multicast cascade interface, wherein the port of the role can receive multicast adding messages and multicast leaving messages, and if a corresponding multicast forwarding table exists, the multicast data stream can be forwarded to the port; and thirdly, the port in the role can not receive the data stream nor any multicast protocol message. By default all ports on a node are invalid ports.

Fig. 1 is a multicast application networking diagram in an ERPS ring network:

the ERPS loop has four nodes, one switch and three OLT devices, wherein the P6 port of OLT3 is set to RPL owner port, the other ports on the node are set to common port, and the initial state of the P6 port protocol of OLT3 is block state because P6 is RPL owner port. The multicast data stream assumes that a multicast address is a and flows to a P1 port of the OLT1 through the switch, because the data stream cannot flow back to the switch through a P1 port, the P1 port can be forcibly configured as a multicast upstream port, at this time, an ONU1 in a slot 1(slot is a slot in the OLT) under the OLT1 sends a multicast join message with the multicast address a, a multicast forwarding table with the multicast address a + multicast VLAN + slot1 is formed at the OLT1, the multicast data stream is forwarded to an ONU1 under the slot1 through a P1 port of the OLT1, and the user can view the channel of the multicast address. The P2 port of OLT1 is by default an invalid port, and we will describe how to determine the multicast role of the P2 port, here we assume that the P2 port is a multicast cascade port.

In order to describe a normal forwarding process, it is also assumed that a P3 and a P4 port of OLT2 are invalid ports by default, and we also assume that a P3 port is a multicast upstream port, a P4 port is a multicast cascade port, an ONU2 under a slot2 of OLT2 sends a multicast join message with a multicast address a, at this time, a multicast forwarding table with a multicast address a + multicast VLAN + slot2 is formed on OLT2, and at the same time, since a P3 port is a multicast upstream port, the join message is also forwarded from the P9 port to a P2 port of OLT1, a multicast forwarding table with a multicast address a + multicast VLAN + P2 is formed on OLT1, at this time, a multicast data stream is forwarded to a P2 port through a P1 port of OLT1, a multicast data message forwarded from a P2 port flows into a P2 port of OLT2, and is forwarded from the multicast forwarding table with a multicast address a + multicast VLAN + slot2 on OLT2 to the P2 port of OLT 2. The user may also view the program.

In the embodiment of the invention, the multicast forwarding table has two structures:

the group of the added messages from the slot ports adopts a first type: the multicast address + the multicast VLAN + the local OLT slot number;

the join message from the multicast cascade interface is grouped into the second type: the multicast address + the multicast VLAN + a multicast cascade interface of the OLT.

For OLT3, since the multicast data stream can only be forwarded from P6 port of OLT3 but cannot be forwarded from P6 port, the port is also forced to be remarked as a multicast upstream port, and since the ERPS forwarding state of P6 port is block state, the user under OLT3 needs to be able to view the multicast program, we assume that P5 is also a multicast upstream port first. Similarly, an ONU3 user at slot3 under OLT3 also views a program, a forwarding table of a multicast address a + multicast VLAN + P4 is newly added at a P4 port of OLT2, a multicast data stream is forwarded from a P4 port through a P3 port of OLT2, a forwarding table of a multicast address a + multicast VLAN + slot3 is available at OLT3, a multicast data stream passing through a P5 port is forwarded from a slot3 of OLT3 to ONU3, and the user under OLT3 can view the channel.

The multicast forwarding process in the ERPS ring network is described based on the multicast port role determination condition, in actual use, the P2-P5 ports are uncertain, and in the case of a link failure, the port roles may also change, for example, in fig. 1, when a link between the switch and the OLT1 fails, the P2 port role needs to be converted into a multicast uplink port from a multicast cascade port, and the roles of the P3-P5 ports also need to be dynamically changed.

Referring to fig. 2, a flowchart of role recovery of an edge node multicast port when a link failure occurs is shown, where the recovery process includes:

s21: setting an OLT (optical line terminal) connected with a multicast server or a switch as a multicast edge node, and configuring a connected uplink port as a multicast uplink port;

the feature that an upstream port of the edge node is connected to the multicast server or the switch determines that the upstream port can only be configured as the multicast upstream port because the data stream does not flow back to the switch. Based on the characteristic, the multicast roles of other ports are dynamically determined by the ERPS forwarding state.

S22: when a link failure occurs or the failure is recovered, the ERPS module notifies the multicast module;

in an ERPS loop, when a link failure occurs, multicast edge nodes OLT in the ring network all receive an ERPS SF message to notify the loop failure, and an ERPS protocol module sets an RPL owner port as forwarding from a previous block port; if the failed link is recovered, the multicast edge node OLT in the ring network receives the ERPS NRRB message, the ERPS protocol module sets the RPL owner port forwarding as block, and the ERPS protocol module notifies the multicast module after the port forwarding state is set.

The message of the ERPS protocol is only one, namely RAPS PDU message, the RAPS PDU message contains ERPS ring information, and the ERPS ring information is transmitted on the ERPS ring so as to realize the intercommunication of the port information of each device. Wherein, the SF type represents Signal Failed RAPS, which indicates that link failure occurs, the NRRB type represents No Request, RPL Blocked, which indicates No failure, and blocks the RPL Owner port. An ERPS ring has only one RPL owner and is prevented from generating a loop in the ERPS ring by blocking the RPL owner port, depending on the user configuration.

S23: the multicast module judges according to the configured ERPS protocol state of the multicast uplink port;

after the ERPS protocol module notifies the multicast module, the multicast module queries the forwarding state of the configured multicast upstream port, as shown in S24 and S25.

S24: judging whether the ERPS state of the multicast uplink port is forwarding, if so, turning to the step S25, otherwise, turning to the step S26;

s25, the multicast module sets other ports as multicast cascade ports;

if the forwarding state of the multicast upstream port configured by a certain edge node in the ERPS ring network is forwarding, it indicates that the multicast upstream port can flow in the multicast data stream, and other ports of the edge node need to be set as multicast cascade ports, because one OLT cannot flow in the data stream from two ports in two directions. As shown in fig. 1, when a link between OLT1 and the switch fails, OLT3 serves as a multicast edge node, its P6 port serves as a multicast upstream port, and at this time, it is set to forwarding by the ERPS protocol, and the multicast module sets the P5 port as a multicast cascade port.

S26: the multicast module sets other ports as multicast uplink ports;

if the forwarding state of the multicast upstream port configured by a certain edge node in the ERPS ring network is block, it indicates that the multicast upstream port does not flow into the multicast data stream, and the multicast data stream must flow into other ports, then other ports of the edge node are set as the multicast upstream ports. As shown in fig. 1, when a link between OLT1 and the switch fails, OLT1 serves as a multicast edge node, its P1 serves as a multicast upstream port, and is set to block by the ERPS protocol, and the multicast module sets the P2 port as the multicast upstream port.

After the P5 of the OLT3 is converted into a multicast cascade port, the OLT3 forwards a multicast general group query message to the P5 port, and the message assists recovery of subsequent non-multicast edge nodes.

Referring to fig. 3, a flowchart of port role recovery of a non-multicast edge node when a link failure occurs is shown, where the recovery process includes:

s31: defaulting equipment which is not configured with the multicast edge node to be a non-edge node;

if the node on the ERPS ring network is not configured as the multicast edge node, the node defaults to be a non-multicast edge node.

S32: when a link failure occurs or the failure is recovered, the ERPS protocol module notifies the multicast module;

when a link failure or failure recovery occurs, the ERPS protocol module notifies the multicast module, and the multicast module sets all port roles as invalid ports at the first time, in which case the OLT does not perform any protocol packet interaction until the multicast port roles are recovered.

S33: a certain port receives the general group inquiry message and is set as a multicast uplink port;

as described in the process of recovering roles of multicast ports of edge nodes, after determining multicast roles of all ports, a multicast edge node forwards a multicast general group query message to a multicast cascade interface, and if a certain port of a non-multicast edge node OLT receives the multicast general group query message, we consider that a link of the port is smooth, and set the upstream port as a multicast upstream port.

S34: other ports are set as multicast cascade ports;

after the multicast uplink port is determined, other uplink ports are set as multicast cascade ports.

As shown in fig. 1, when a link between OLT1 and a switch fails, a non-multicast edge node OLT2 sets the multicast port roles of a P3 port and a P4 port of OLT2 as invalid ports, and after receiving a multicast general group query message forwarded by a P5 port of OLT3, sets a P4 port that receives the message as a multicast upstream port, and sets other ports, for example, a P3 port as a multicast cascade port.

Fig. 4 is a diagram showing recovery of the ERPS ring network multicast service when a link failure occurs:

as described above, when a link failure occurs between OLT1 and the switch, after setting the forwarding state of the P6 port as forwarding and setting the P5 port as a multicast cascade port, the non-multicast edge node device OLT3 clears all local forwarding tables and forwards a multicast general group query message to all slots and multicast cascade ports, and after receiving the query message, ONU3 under slot3 of OLT3 sends an add message with multicast address a, a multicast forwarding table with multicast address a + multicast VLAN + slot3 is formed on OLT3, and forwards the multicast add message through the P6 port of OLT3, and the multicast data stream is forwarded to ONU3 under slot3 through the P6 port, so that the multicast service of the user is recovered.

Meanwhile, after setting a P3 port as a multicast cascade port and a P4 port as a multicast uplink port, the non-multicast edge node OLT2 may also forward a multicast general group query message to all slots and multicast cascade ports, and after receiving the multicast general group query message, OLT2 may also clear all forwarding tables, and after receiving the multicast general group query message, ONU2 of slot2 under OLT2 may send a join message with a multicast address of a, and OLT2 forms a forwarding table of multicast address a + multicast VLAN + slot2, and forwards the join message from a P4 port, OLT3 forms a forwarding table of multicast address a + multicast VLAN + P5, and multicast data flows through a P4 port of OLT2 and is forwarded to ONU2 users under slot2 of OLT2, so that the multicast service of the user is also recovered.

Similarly, multicast service recovery under OLT1 forms a forwarding table of multicast address a + multicast VLAN + P3 on OLT2, and forms a forwarding table of multicast address a + multicast VLAN + slot1 on OLT1, and multicast data stream is forwarded to ONU1 of slot1 through P2 port of OLT1, so that multicast service recovery is performed.

Fig. 5 is a sequence diagram for opening an ERPS ring network multicast service, where the opening process includes:

s51: setting parameters and configuration of an ERPS protocol, and firstly enabling the ERPS protocol in the loop to normally operate;

when the ERPS ring network is opened, firstly, the parameter configuration of the ERPS protocol needs to be set, and the port forwarding state of the RPL owner port is ensured to be block when the ERPS protocol normally operates.

S52: configuring multicast edge nodes through a network manager or a command line;

the OLT connected to the multicast server or the switch is set as a multicast edge node.

S53: other nodes are defaulted to be multicast non-edge nodes without any operation;

other OLTs default to non-multicast edge nodes and do not need to be configured.

S54: the multicast edge node and the non-edge node respectively recover the port role, and the multicast service is recovered to be normal;

when a certain OLT is set as a multicast edge node through a command line or a network manager, a multicast module is notified, the multicast module sets multicast roles of all ports according to the above process and forwards a multicast general group query message to a multicast cascade interface, and multicast service under the OLT of the multicast edge node can be recovered. The ports of other non-multicast edge nodes are all the invalid ports by default, and normal service opening can be obtained according to the scheme.

Fig. 6 is a service recovery diagram during the extension of the ERPS node:

when an OLT needs to be added newly in the ERPS loop, as shown in fig. 6, a P6 port of OLT3 is an RPL owner port and is set as a multicast uplink port, if an OLT4 is added between OLT1 and OLT2, when a link between OLT1 and OLT2 is disconnected, a link failure occurs in the ERPS loop, and OLT1 is a multicast edge node, and a multicast port angle and a multicast data stream forwarding direction of the OLT1 do not change, but a P6 port of OLT3 is converted from a block state to a forwarding state, and then a P5 port of OLT3 is set as a multicast cascade port. Meanwhile, the OLT2 acts as a non-multicast edge node, and its P4 port is set as a multicast upstream port and P3 port is set as a multicast cascade port.

After the P2 port of the OLT1 and the P7 port of the OLT4 are connected, the OLT4 serves as a non-multicast edge node, the P7 port of the OLT is recovered as a multicast upstream port, and the P8 port recovers a multicast cascade port; when the P3 port of OLT2 and the P8 port of OLT4 are connected, for protection, the ERPS protocol sets both the P3 port and the P8 port to block state, and after a back-cut latency time, the loop will be back-cut, the RPL owner port is reset to block state, then the nodes on the ERPS ring recover again according to the above described scheme, and finally the data flow is as shown in fig. 6.

Further, the present invention also provides a system for implementing multicast protocol in ERPS ring network, including multicast edge node and non-multicast edge node, wherein:

Further, when a link of a node OLT in the ERPS ring network fails or a port state changes, an ERPS protocol module on the OLT notifies a multicast module after processing a flow of the protocol and setting a corresponding port as block or forwarding;

Further, after determining the roles of all the ports, the multicast edge node forwards the multicast general group query message to all the multicast cascade interfaces under the node.

Further, if a certain port of the non-multicast edge node receives the multicast general group query message, the invalid port is modified into a multicast uplink port, and the rest other ports are modified into multicast cascade ports;

Further, the structure of the multicast forwarding table is as follows:

According to the technical scheme of the invention, the new OLT on the ERPS ring only needs to be manually inserted into the ERPS ring node and can be recovered without any configuration operation on the multicast service.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A method for realizing multicast protocol in ERPS ring network is characterized in that the method comprises:

dividing all nodes OLT (Optical Line Terminal) in an ERPS (Ethernet Ring Protection Switching) Ring network into two types, wherein equipment connected with a multicast server or a switch is divided into multicast edge nodes, and other nodes are divided into non-multicast edge nodes;

a port connected with a multicast edge node and a multicast server or a switch is forcibly configured as a multicast uplink port, and the multicast uplink port can only enter a multicast data stream and cannot forward the multicast data stream; all the initial ports of the non-multicast edge node are invalid ports;

the ports on the multicast edge node and the non-multicast edge node are configured as a multicast uplink port, a multicast cascade port or an invalid port, wherein: the multicast uplink port can receive multicast data stream and can receive multicast general group query message at the same time, after receiving the multicast general group query message, the OLT can forward all the current multicast address conditions from the multicast uplink port in a message adding mode; the multicast cascade interface can receive the multicast adding message and the multicast leaving message, if the corresponding multicast forwarding table exists, the multicast data stream can be forwarded to the multicast cascade interface; the invalid port can not receive data stream nor any multicast protocol message;

when a link of a node OLT on an ERPS ring network fails or a port state changes, an ERPS protocol module on the OLT notifies a multicast module after processing the flow of the protocol and setting a corresponding port as block or forwarding;

if the node is a multicast edge node, a port connected with the multicast server is configured as a multicast uplink port, the multicast module inquires the port forwarding state of the multicast uplink port after being notified, and if the multicast uplink port is in a block state, other ports of the multicast edge node are set as the multicast uplink ports; if the multicast upstream port is in forwarding state, setting other ports of the multicast edge node as multicast cascade ports;

after determining the roles of all ports, the multicast edge node forwards a multicast general group query message to all multicast cascade interfaces under the node;

if a certain port of the non-multicast edge node receives the multicast general group inquiry message, the invalid port is modified into a multicast uplink port, and other remaining ports are modified into multicast cascade ports;

2. The method for implementing multicast protocol in ERPS ring network of claim 1, wherein the structure of the multicast forwarding table is:

the added messages from the slot ports are grouped and adopted: multicast address + multicast VLAN (Virtual Local Area Network ) + number of slot of the OLT (slot is slot in the OLT);

the joining message from the multicast cascade interface is grouped and adopted: multicast address + multicast VLAN + the multicast cascade interface.

3. A system for realizing multicast protocol in ERPS ring network is characterized in that it includes multicast edge node and non-multicast edge node, in which:

the multicast edge node refers to a device connected with a multicast server or a switch in an ERPS (Ethernet Ring Protection Switching, Ethernet multi-Ring Protection technology) Ring network, and a port connected with the multicast server or the switch is forcibly configured as a multicast uplink port, and the multicast uplink port can only perform multicast data stream and cannot forward the multicast data stream; the non-multicast edge node refers to other nodes in the ERPS ring network, and all initial ports of the non-multicast edge node are invalid ports;

the ports on the multicast edge node and the non-multicast edge node are configured as a multicast uplink port, a multicast cascade port or an invalid port, wherein: the multicast uplink port can receive multicast data stream and multicast general group query message, after receiving the multicast general group query message, the OLT (Optical Line Terminal) can forward all current multicast address conditions from the multicast uplink port by adding message; the multicast cascade interface can receive the multicast adding message and the multicast leaving message, if the corresponding multicast forwarding table exists, the multicast data stream can be forwarded to the multicast cascade interface; the invalid port can not receive data stream nor any multicast protocol message;

4. The system for implementing multicast protocol in ERPS ring network of claim 3, wherein the structure of the multicast forwarding table is: