Patent Publication Number: US-2018054324-A1

Title: System and method for integrating redundant ring and rapid spanning tree protocol (rstp)

Description:
TECHNICAL FIELD 
     The present invention relates to a network system and a method thereof, and more particularly to a system and a method for integrating redundant ring and Rapid Spanning Tree Protocol (RSTP) that increase, in a group manner, a quantity of devices running the RSTP and allow a connection between a redundant ring and a device running the RSTP. 
     BACKGROUND 
     In recent years, with popularity of the Internet, network topologies and network protocols become increasingly complex, or even can hardly be integrated, for example, a redundant ring protocol such as High-availability Seamless Redundancy (HSR) can hardly run concurrently with Rapid Spanning Tree Protocol (RSTP), leading to a failure of a redundancy mechanism of a whole network topology. 
     Generally, conventional devices running the RSTP can be connected by using any network topology. However, devices such as an intelligent electronic device (IED) or a programmable logic controller (PLC) are generally connected by means of a daisy chain, for example, and when the devices are connected to a switch, the switch also needs to run the RSTP, so as to form a large RSTP network. However, the RSTP has a maximum topology limit, causing that a network architecture is limited in size and cannot be expanded into a large network. In addition, when a network topology requirement changes, the network topology is also limited to being connected to a device running the RSTP, and there is a problem of poor scalability of the network architecture. 
     In view of the above, some manufactures propose to integrate a device running the RSTP with another ring, for example, Resilient Ethernet Protocol (REP), DT-Ring, S-Ring, MRP-Ring, and the like, so as to enable the redundancy mechanism and the RSTP to run concurrently. However, these manners are still limited to the maximum topology limit of the RSTP, and fail to effectively solve the problem of the poor scalability of the network architecture. 
     To sum up, it can be know that the problem of poor scalability of the network architecture has been existed in the prior art for a long time. Therefore, it is necessary to provide an improved technical means, so as to solve the problem. 
     SUMMARY 
     The present invention discloses a system and a method for integrating redundant ring and Rapid Spanning Tree Protocol (RSTP). 
     First, the present invention discloses a system for integrating redundant ring and RSTP. The system includes: an HSR ring and a network topology. The HSR ring includes ring nodes. Each ring node includes a transmission module, a detection module, and a forwarding module. The transmission module is configured to transmit a Bridge Protocol Data Unit (BPDU) and includes: two first ports and a second port. Each of the two first ports is configured to be connected to one of two first ports of each of two different ring nodes, so as to form an HSR ring. The second port is configured to be connected to a first endpoint device or a second endpoint device running the RSTP, and is allowed to set a mode message and a group ID, where when the mode message is a transparent mode, forwarding the BPDU is allowed. The detection module is configured to detect, when the BPDU is received from the outside, a transmission source of the BPDU and a group to which the BPDU belongs. The forwarding module is configured to embed, when the transmission source is the second port, the group ID of the second port receiving the BPDU into the BPDU as the group to which the BPDU belongs, and forward the BPDU to the two first ports; and configured to compare, when the transmission source is one of the two first ports, the group to which the BPDU belongs with the group ID of the second port, and delete, if a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forward the BPDU to the second port. With regard to the part of the network topology, each network topology includes at least a first endpoint device and a second endpoint device, and the first endpoint device and the second endpoint device of the network topology are separately connected to second ports with the same group ID in different ring nodes, so as to form a corresponding RSTP group. 
     In addition, the present invention further discloses a system for integrating redundant ring and Rapid Spanning Tree Protocol (RSTP), which is applied to a plurality of ring nodes that form a redundant ring. The system includes: a transmission module, a detection module, and a forwarding module. The transmission module is configured to transmit a Bridge Protocol Data Unit (BPDU) and includes two first ports and at least one second port. Each of the two first ports is configured to be connected to one of two first ports of each of two different ring nodes, so as to form the redundant ring. The second port is configured to be connected to a first endpoint device or a second endpoint device, running the RSTP, of a network topology, and is allowed to set a mode message and a group ID. When the mode message is a transparent mode, forwarding the BPDU is allowed. The first endpoint device and the second endpoint device of the network topology are separately connected to second ports with the same group ID, so as to form a corresponding RSTP group. The detection module is configured to detect, when the BPDU is received from the outside, a transmission source of the BPDU and a group to which the BPDU belongs. The forwarding module is configured to embed, when the transmission source is the second port, the group ID of the second port receiving the BPDU into the BPDU as the group to which the BPDU belongs; is configured to compare the group to which the BPDU belongs with a group ID of another second port, forward, if a comparison result is inconsistency, the BPDU to the first ports, and forward, if a comparison result is consistency, the BPDU to the consistent second port; and is configured to compare, when the transmission source is one the two first ports, the group to which the BPDU belongs with the group ID of the second port, forward, if a comparison result is inconsistency, the BPDU to the other first port, and delete, if a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forward the BPDU to the consistent second port. 
     Subsequently, the present invention discloses a method for integrating redundant ring and Rapid Spanning Tree Protocol (RSTP), and steps of the method include: providing a High-availability Seamless Redundancy (HSR) ring, where the HSR ring includes a plurality of ring nodes, and each of two first ports of each ring node is connected to one of two first ports of each of two different ring nodes; connecting a second port of each ring node to a first endpoint device or a second endpoint device running the RSTP, and allowing the second port to set a mode message and a group ID, where when the mode message is a transparent mode, the second port allows forwarding of a Bridge Protocol Data Unit (BPDU); providing at least one network topology, where each network topology includes at least a first endpoint device and a second endpoint device, and the first endpoint device and the second endpoint device of the network topology are separately connected to second ports with the same group ID in different ring nodes, so as to form a corresponding RSTP group; detecting, when the ring node receives the BPDU from the outside, a transmission source of the BPDU and a group to which the BPDU belongs; embedding, when the transmission source is the second port, the group ID of the second port receiving the BPDU into the BPDU as the group to which the BPDU belongs by the ring node, and forwarding the BPDU to the two first ports; and comparing, when the transmission source is one of the two first ports, the group to which the BPDU belongs with the group ID of the second port, forwarding, if a comparison result is inconsistency, the BPDU to the other first port, and deleting, if a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forwarding the BPDU to the second port. 
     In addition, the present invention further discloses a method for method for integrating redundant ring and Rapid Spanning Tree Protocol (RSTP), which is applied to a plurality of ring nodes that form a redundant ring, where each ring node includes two first ports and at least one second port; each of the two first ports is connected to one of two first ports of each of two different ring nodes; the second port is connected to a first endpoint device or a second endpoint device, running the RSTP, of a network topology; the first endpoint device and the second endpoint device of the network topology are separately connected to second ports with the same group ID, so as to form a corresponding RSTP group; and steps of the method include: allowing the second port by the ring node to set a mode message and the group ID, where when the mode message is a transparent mode, the second port allows forwarding of a Bridge Protocol Data Unit (BPDU); detecting, when the ring node receives the BPDU from the outside, a transmission source of the BPDU and a group to which the BPDU belongs; embedding, when the transmission source is the second port, the group ID of the second port receiving the BPDU into the BPDU as the group to which the BPDU belongs by the ring node, and comparing the group to which the BPDU belongs with a group ID of another second port, forwarding, if a comparison result is inconsistency, the BPDU to the first ports, and forwarding, if a comparison result is consistency, the BPDU to the consistent second port; and comparing, when the transmission source is one of the two first ports, the group to which the BPDU belongs with the group ID of the second port by the ring node, forwarding, if a comparison result is inconsistency, the BPDU to the other first port, and deleting, if a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forwarding the BPDU to the consistent second port. 
     The systems and methods disclosed by the present invention are described as above, and differ from the prior art in that a mode message and a group ID are set for a ring node of a redundant ring, such that in a network environment in which redundant ring and RSTP run concurrently, the ring node allows, according to the group ID when the mode message is a transparent mode, forwarding of a BPDU to a consistent network topology, and each network topology is converged to a steady state RSTP domain. 
     By means of the foregoing technical means, the present invention can achieve the technical effect of improving the scalability of the network architecture. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a block diagram of a system for integrating redundant ring and RSTP according to the present invention; 
         FIG. 2A  and  FIG. 2B  are a flowchart of a method for integrating redundant ring and RSTP according to the present invention; 
         FIG. 3  is a block diagram of another system for integrating redundant ring and RSTP according to the present invention; 
         FIG. 4  is a flowchart of another method for integrating redundant ring and RSTP according to the present invention; 
         FIG. 5  is a schematic diagram of communication between virtual local area networks (VLANs) and RSTP groups carried out by using the present invention; and 
         FIG. 6  is a schematic diagram of setting a mode message and a group ID by using the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Implementation of the present invention is illustrated below in detail with reference to the drawings and embodiments, so as to enable an implementation process, in which the present invention applies the technical means to solve the technical problem and achieve the technical effect, to be fully understood and implemented accordingly. 
     Before the system and the method for integrating redundant ring and RSTP disclosed by the present invention are described, first, terms defined by the present invention are described. A first port in the present invention refers to a port that is used in forming a redundant ring, and a second port in the present invention refers to a port for connecting a network topology to a switch. In practical implementation, one end of a network topology connected to a redundant ring is called a first endpoint device, and the other end of the network topology connected to the redundant ring is called a second endpoint device; and a second port is a port connected to the first endpoint device or the second endpoint device. In addition, in a transparent mode of the present invention, forwarding a BPDU to a port capable of forwarding is allowed, but a BPDU is not forwarded to a blocking port, and an RSTP is not processed, that is, a second port is in a state of the RSTP being closed. It should be noted that, a device such as the IED or the PLC is preset in a state of the RSTP being opened, but a second port of a ring node (alternatively called a switch) on a redundant ring can form a corresponding RSTP group with the device such as the IED or the PLC in a network topology only when the second port is in a state of the RSTP being closed, so as to prevent all the network topologies from forming a same RSTP group. If the second port opens the RSTP, at this time, the second port is unable to form corresponding RSTP groups for different network topologies, and when the ring node receives bridge protocol data, the ring node forwards the bridge protocol data according to the normal RSTP. 
     The following further describes the system and method for integrating redundant ring and RSTP of the present invention with reference to drawings. Referring to  FIG. 1 ,  FIG. 1  is a block diagram of a system for integrating redundant ring and RSTP according to the present invention. The system includes: an HSR ring  10  and a network topology  20 . The HSR ring  10  includes a plurality of ring nodes  100 . In practical implementation, a ring node  100  is a switch or a computer device with a same function. In addition, each device in the network topology  20  runs the RSTP, and includes at least a first endpoint device  21  and a second endpoint device  22 . The first endpoint device  21  and the second endpoint device  22  of the network topology are separately connected to second ports  112  with a same group ID in different ring nodes  100 , so as to form a corresponding RSTP group, and the RSTP group corresponds to the group ID of the second ports. Instead of using a same root, the RSTP groups with different group IDs have respective RSTP roots. Therefore, a quantity of devices in each RSTP group can achieve a maximum topology limit of the RSTP, thereby improving the scalability of the network architecture. The first endpoint device  21  and the second endpoint device  22  may be computer devices running the RSTP, for example, IED, PLC, and the like. It should be noted that although the network topology  20  shown in  FIG. 1  is a chain network, the type of the network topology  20  of the present invention is not limited thereto. In other words, any network topology capable of running the RSTP falls within the application scope of the present invention. 
     With regard to the part of the ring nodes  100 , each ring node  100  includes: a transmission module  110 , a detection module  120 , and a forwarding module  130 . The transmission module  110  is configured to transmit a BPDU, and the transmission module  110  includes: two first ports  111  and a second port  112 . Each of the two first ports  111  is connected to one of two first ports  111  of each of two different ring nodes  100 , so as to form the HSR ring  10 . The second port  112  is configured to be connected to the first endpoint device  21  or the second endpoint device  22  running the RSTP, and is allowed to set a mode message and a group ID. When the mode message is a transparent mode, the second port  112  is in a state of the RSTP being closed, and forwarding the BPDU is allowed. When the mode message is not a transparent mode and the second port  112  closes the RSTP, the second port  112  drops the received BPDU. It should be noted that when the mode message is not the transparent mode, if the BPDU is received by one first port  111 , the ring node  100  directly forwards the BPDU received from the first port  111  to the other first port  111 . 
     The detection module  120  is configured to detect, when the BPDU is received from the outside, a transmission source of the BPDU and a group to which the BPDU belongs. The outside refers to the outside of the device of the ring node  100 . Therefore, both of the HSR ring  10  and the network topology  20  are located at the outside of the ring node  100 . In practical implementation, the detection of a transmission source is determined by a particular port that receives the BPDU; the transmission source being the first port  111  represents that the BPDU is from the HSR ring  10 ; and the transmission source being the second port  112  represents that the BPDU is from the network topology  20 . In addition, the detection of a group to which the BPDU belongs is determined by system ID extension, and the system ID extension is of 12 bits and records a group ID. Therefore, the group to which the BPDU belongs can be acquired by reading the group ID. It should be noted that, if the transmission source is the second port  112 , at this time, the group ID is not embedded into the BPDU, and therefore, the group to which the BPDU belongs is determined by the group ID of the second port  112 . 
     The forwarding module  130  is configured to embed, when the transmission source is the second port  112 , the group ID of the second port  112  receiving the BPDU into the BPDU, where the group with the group ID is the group to which the BPDU belongs, and forward the BPDU to the two first ports  111 ; and is configured to compare, when the transmission source is one of the two first ports  111 , the group to which the BPDU belongs with the group ID of the second port  112 , forward, if a comparison result is inconsistency, the BPDU to the other first port  111 , and delete, when a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forward the BPDU to the second port  112 . The network topologies  20  are grouped according to group IDs. Therefore, even in a case in which the HSR and the RSTP run concurrently, a network breakdown caused by occupation of an overall network by a broadcast packet or a multicast packet can be effectively avoided. 
     Subsequently, referring to  FIG. 2A  and  FIG. 2B ,  FIG. 2A  and  FIG. 2B  are a flowchart of a method for integrating redundant ring and RSTP, and steps of the method include: providing an HSR ring  10 , where the HSR ring  10  includes a plurality of ring nodes  100 , and each of two first ports  111  of each ring node  100  is connected to one of two first ports  111  of each of two different ring nodes  100  (step  210 ); connecting a second port  112  of each ring node  100  to a first endpoint device  21  or a second endpoint device  22  running the RSTP, and allowing the second port  112  to set a mode message and a group ID, where when the mode message is a transparent mode, the second port  112  allows forwarding of a BPDU (step  220 ); providing at least one network topology  20 , where each network topology  20  includes at least a first endpoint device  21  and a second endpoint device  22 , and the first endpoint device  21  and the second endpoint device  22  of the network topology  20  are separately connected to second ports  112  with the same group ID in different ring nodes  100 , so as to form a corresponding RSTP group (step  230 ); detecting, when the ring node  100  receives a BPDU from the outside, a transmission source of the BPDU and a group to which the BPDU belongs (step  240 ); embedding, when the transmission source is the second port  112 , the group ID of the second port  112  receiving the BPDU into the BPDU as the group to which the BPDU belongs by the ring node  100 , and forwarding the BPDU to the two first ports  111  (step  250 ); and comparing, when the transmission source is one of the two first ports  111 , the group to which the BPDU belongs with the group ID of the second port  112  by the ring node, forwarding, when a comparison result is inconsistency, the BPDU to the other first port  111 , and deleting, when a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forwarding the BPDU to the second port (step  260 ). By means of the foregoing steps, a mode message and a group ID are set for the ring node  100  of the HSR ring  10 , such that in a network environment in which the HSR ring  10  and the RSTP run concurrently, the ring node  100  allows, according to the group ID when the mode message is a transparent mode, forwarding of a BPDU to a consistent network topology  20 , and each network topology  20  is converged to a steady state RSTP domain. 
     It should be additionally noted that in step  220 , when the mode message is not a transparent mode and the second port  112  closes the RSTP, the BPDU received by the second port  112  may be directly discarded, and the BPDU received by one first port  111  is forwarded to the other first port  111 . 
     Subsequently, referring to  FIG. 3 ,  FIG. 3  is a block diagram of another system for integrating redundant ring and RSTP according to the present invention. The system is applied to ring nodes  300  of a redundant ring  40 . The system includes: a transmission module  310 , a detection module  320 , and a forwarding module  330 . The transmission module  310  is configured to transmit a BPDU and includes two first ports  311  and at least one second ports  312 . Each of the two first ports  311  is configured to be connected to one of two first ports  311  of each of two different ring nodes  300 , so as to form the redundant ring  40 . Each second port  312  is configured to be connected to a first endpoint device ( 21 ,  22 ) or a second endpoint device ( 31 ,  32 ), running the RSTP, of a network topology ( 20 ,  30 ), and is allowed to set a mode message and a group ID, where when the mode message is a transparent mode, forwarding a BPDU is allowed; and the first endpoint device ( 21 ,  22 ) and the second endpoint device ( 31 ,  32 ) of the network topology ( 20 ,  30 ) are separately connected to second ports  312  with the same group ID, so as to form a corresponding RSTP group. The transmission module  310  is similar to the transmission module  110  shown in  FIG. 1 , and differs from the transmission module  110  shown in  FIG. 1  in that a ring node  300  may have a plurality of second ports  312 , and the first ports  311  are connected to the redundant ring  40  rather than the HSR ring  10  shown in  FIG. 1 . 
     The detection module  320  is configured to detect, when the BPDU is received from the outside, a transmission source of the BPDU and a group to which the BPDU belongs. The detection module  320  here is the same as the detection module  120  shown in  FIG. 1 , and is not described in detail herein again. 
     The forwarding module  330  is configured to embed, when the transmission source is the second port  312 , the group ID of the second port  312  receiving the BPDU into the BPDU, where the group with the group ID is the group to which the BPDU belongs; is configured to compare the group to which the BPDU belongs with a group ID of another second port  312 , forward, if a comparison result is inconsistency, the BPDU to the first ports  311 , and forward, if a comparison result is consistency, the BPDU to the consistent second port  312 ; and is configured to compare, when the transmission source is one the two first ports  311 , the group to which the BPDU belongs with the group ID of the second port  312 , forward, if a comparison result is inconsistency, the BPDU to the other first port  311 , and delete, if a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forward the BPDU to the consistent second port  312 . In other words, the forwarding module  330  performs corresponding forwarding according to a port receiving the BPDU. If a port receiving the BPDU is the second port  312 , the group ID of the second port  312  is embedded (alternatively called labeled) in a packet. If a group ID of another second port  312  on the ring node  300  is the same as the group ID of the second port  312 , the BPDU is forwarded to the second port  312  having the same group ID, and otherwise, the BPDU is forwarded to the first ports  311 . If a port receiving the BPDU is one of the first ports  311 , it is checked whether the group to which the BPDU belongs that is embedded in a packet is the same as the group ID of the second port  312  on the ring node  300 , and if yes, the group ID of the packet is removed, and the BPDU is forwarded to the second port  312  with the same group ID, and otherwise, the BPDU is forwarded to the other first port  311 . The forwarding module  330  is similar to the forwarding module  330  shown in  FIG. 1 , and differs from the forwarding module  130  shown in  FIG. 1  in that determining group IDs of a plurality of second ports  312  is added, and a corresponding forwarding process is performed on the basis of a determining result. 
     As shown in  FIG. 4 ,  FIG. 4  is a flowchart of another method for integrating redundant ring and RSTP according to the present invention. The method is applied to a plurality of ring nodes  300  that form a redundant ring  40 , where each ring node  300  includes two first ports  311  and at least one second port  312 ; each of the two first ports  311  is connected to one of two first ports  311  of each of two different ring nodes  300 ; the second port  312  is connected to a first endpoint device ( 21 ,  32 ) or a second endpoint device ( 22 ,  32 ), running the RSTP, of a network topology ( 20 ,  30 ); the first endpoint device ( 21 ,  31 ) and the second endpoint device ( 22 ,  32 ) of the network topology ( 20 ,  30 ) are separately connected to second ports  312  with the same group ID, so as to form a corresponding RSTP group; and steps of the method include: allowing the second port  312  by the ring node  300  to set a mode message and a group ID, where when the mode message is a transparent mode, the second port  312  allows forwarding of a BPDU (step  310 ); detecting, when the ring node  300  receives a BPDU from the outside, a transmission source of the BPDU and a group to which the BPDU belongs (step  320 ); embedding, when the transmission source is the second port  312 , the group ID of the second port  312  receiving the BPDU into the BPDU as the group to which the BPDU belongs by the ring node  300 , comparing the group to which the BPDU belongs with a group ID of another second port  312 , forwarding, if a comparison result is inconsistency, the BPDU to the first ports  311 , and forwarding, if a comparison result is consistency, the BPDU to the consistent second port  312  (step  330 ); and comparing, when the transmission source is one of the two first ports  311 , the group to which the BPDU belongs with the group ID of the second port  312  by the ring node  300 , forwarding, if a comparison result is inconsistency, the BPDU to the other first port  311 , and deleting, if a comparison result is consistency, the group to which the BPDU belongs in the BPDU and forwarding the BPDU to the consistent second port  312  (step  340 ). By means of the foregoing steps, a mode message and a group ID are set for the ring node  300  of the HSR ring  40 , such that in a network environment in which the HSR ring  40  and the RSTP run concurrently, the ring node  300  allows, according to the group ID when the mode message is a transparent mode, forwarding of a BPDU to a consistent network topology ( 20 ,  30 ), and each network topology ( 20 ,  30 ) is converged to a steady state RSTP domain. In practical implementation, the mode message and the group ID are set by logging in the ring node  300  and using a preset graphical user interface or instruction, which is described later with reference to the drawings. 
     It should be additionally noted that in step  310 , when the mode message is not a transparent mode and the second port  312  closes the RSTP, the BPDU received by the second port  312  may be directly discarded, and the BPDU received by one of the two first port  311  is forwarded to the other first port  311 . 
     The following description is made in a manner of embodiments with reference to  FIG. 5  and  FIG. 6 . First, referring to  FIG. 5 ,  FIG. 5  is a schematic diagram of communication between VLANs and RSTP groups carried out by using the present invention. It is mentioned earlier that a network topology  20  includes a first endpoint device  21  and a second endpoint device  22 . However, in practical implementation, the network topology  20  may further include a plurality of terminal devices  23 . Besides, the HSR ring  10  may be further connected to a plurality of network topologies, for example, a network topology  50 . The network topology  50  also includes a first endpoint device  21 , a second endpoint device  22 , and terminal devices  23 . Different network topologies may be connected to adjacent ring nodes, as shown in  FIG. 5 , the network topology  20  is connected to adjacent ring nodes ( 100   a,    100   b ), and the network topology  50  is connected to adjacent ring nodes ( 100   c,    100   d ). Subsequently, an RSTP group (that is, a network topology) may work with a VLAN to manage a network, and each RSTP group corresponds to a VLAN, for example, a VLAN of an “RSTP group  1 ” is a “VLAN  10 ”, and a VLAN of an “RSTP group  2 ” is a “VLAN  20 ”. When a terminal  60  that is also in the “VLAN  20 ” intends to communicate with a device in the network topology  20 , before the “RSTP group  1 ” is distinguished from the “RSTP group  2 ”, such a connection manner causes a failure of an RSTP mechanism even though the VLANs are used for separation, and all ports are in states of forwarding, which works together with the HSR ring  10 , leading to a network breakdown caused by occupation of an overall network by broadcast and multicast packets. After the “RSTP group  1 ” is distinguished from the “RSTP group  2 ”, when a BPDU is forwarded, the BPDU may be only forwarded to a same RSTP group according to a group ID, for example, a BPDU received by the ring node  100   c  from the network topology  50  is transmitted by using the HSR ring  10 , and besides the ring node  100   d,  other ring nodes ( 100   a  and  100   b ) do not forward the BPDU to the network topology  20 . Therefore, each network topology ( 20 ,  50 ) is converged to a steady state RSTP domain. 
     As shown in  FIG. 6 ,  FIG. 6  is a schematic diagram of setting a mode message and a group ID by using the present invention. In practical implementation, a mode message and a group ID of a second port of a ring node are set by logging in a graphical user interface  600  displayed on the ring node. After logging in the ring node, a user may select, according to a port number of a second port displayed on a port number display block  610 , to set a corresponding mode message and a group ID in a mode setting block  620  and a group setting block  630 , for example, a ring node has a plurality of second ports, and a user needs to be in a third enable transparent mode and to set a group ID as a value 1. At this time, as shown in  FIG. 6 , a corresponding selection block in the mode setting block  620  is set by using a cursor click mode, a value 1 is typed into a corresponding place in the group setting block  630 , and a determining element  640  is clicked, so as to complete the setting. If resetting is needed, a resetting element  650  may be clicked to restore to factory reset. 
     To sum up, it can be known that the present invention differs from the prior art in that, a mode message and a group ID are set for each ring node of a redundant ring, such that in a network environment in which the redundant ring and the RSTP run concurrently, the ring node allows, when the mode message is a transparent mode, to forward, according to the group ID, a BPDU to a consistent network topology, and enables each network topology to be converged to a steady state RSTP domain. By means of this technical means, the problem that a redundant ring and an RSTP cannot run concurrently existing in the prior art can be resolved, thereby achieving the technical effect of improving the scalability of the network architecture.