JP4011497B2 - Transmission apparatus and data reception control method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission apparatus and a data reception control method thereof, for example, an asynchronous transmission path accommodation method in a digital transmission apparatus.
[0002]
[Prior art]
In an asynchronous network such as Ethernet (registered trademark), when a network is constructed with a plurality of transmission paths, a redundant configuration is generally considered and nodes are configured with a plurality of paths. In this case, the same data from a plurality of paths flows into the node. For this reason, only one path is used between nodes by the spanning tree (STP), and when a line failure occurs in this path, the path is switched to another path. In this way, network redundancy is configured.
[0003]
In a device having a plurality of ports such as a bridge device, the STP determines a network route by transmitting a route establishment frame to each port. For this reason, a network (as shown in FIG. 14) configured by a plurality of SDH (Synchronuos Digital Hierarchy) transmission apparatuses (sometimes referred to as “nodes”) and passing a plurality of paths through the same band on the optical line. In a synchronous (optical) network, even when data is not communicated only with a specific node, it cannot be switched to a line to the LAN side, and a redundant configuration cannot be performed.
[0004]
In addition, in the network system shown in FIG. 14, in order to construct a redundant configuration, a configuration can be considered in which a logical path is constructed with all nodes and an STP confirmation frame is transmitted for each path. In this case, if the number of nodes in the network increases, the number of STP confirmation frames also doubles the number of nodes and the number of frames increases, which may cause synchronization (optical) transmission path congestion.
[0005]
For example, in a network with 1024 nodes as shown in FIG. 15, when the STP confirmation frame is transmitted between the nodes, the following number of frames is output by one transmission / reception of the confirmation frame.
Number of nodes 1024 x number of opposite nodes 1023
= 1,477,552 frames
Such transmission / reception of a confirmation frame may cause network congestion.
[0006]
As a prior art related to the invention of the present application, there is an invention related to a digital transmission apparatus described in Japanese Patent Application No. 2000-333735 filed by the applicant of the present application.
[0007]
[Problems to be solved by the invention]
One of the objects of the present invention is to provide a technique capable of constructing a redundant configuration capable of receiving data from one of the first and second transmission lines with another transmission apparatus.
[0008]
Another object of the present invention is to provide a technique capable of suppressing the occurrence of congestion in the second transmission path.
[0009]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above-described problems.
[0010]
That is, the first aspect of the present invention is: Connected to a synchronous network with other transmission devices A transmission device,
Said A connection confirmation frame that is sent periodically from another transmission device and includes the address of that transmission device. An asynchronous transmission path constituting an asynchronous network connecting the other transmission apparatus and the transmission apparatus; The first transmission line and It is a synchronous transmission path constituting the synchronous network Receiving means capable of receiving from both of the second transmission lines;
The connection confirmation frame Said When receiving from both the first and second transmission paths, the other transmission device sends the first 2 If the setting is made not to receive the data transferred through the other transmission path and the connection confirmation frame cannot be received from the other transmission apparatus through the first transmission path for a predetermined time, the second transmission path from the other transmission apparatus Receiving control means for setting to receive data transferred through the transmission line.
[0011]
The transmission apparatus according to the present invention is applied to a digital transmission apparatus such as an SDH transmission apparatus. The second transmission path is, for example, a synchronous transmission path set on a ring-shaped synchronous network constructed by the transmission apparatus together with other transmission apparatuses, and the first transmission path is, for example, the transmission apparatus and other transmissions. This is an asynchronous transmission line constructed by connecting asynchronous networks accommodated by devices with asynchronous lines.
[0012]
The second aspect of the present invention is: Connected to a synchronous network with other transmission devices A transmission device,
The data including the source address An asynchronous transmission path constituting an asynchronous network connecting the other transmission apparatus and the transmission apparatus; The data that can be received from the first transmission path and is given the address of another transmission device It is a synchronous transmission path constituting the synchronous network Receiving means capable of receiving from the second transmission path;
When the data having the same source address is received from both the first and second transmission paths, the first 2 If the data transferred through the transmission line is not received and the data cannot be received through the first transmission line for a predetermined time, the data is transferred from the other transmission apparatus through the second transmission line. Receiving control means for setting to receive the data.
[0013]
The third aspect of the present invention is: Connected to a synchronous network with other transmission devices A data reception control method for a transmission device,
Said A connection confirmation frame that is sent periodically from another transmission device and includes the address of that transmission device. An asynchronous transmission path constituting an asynchronous network connecting the other transmission apparatus and the transmission apparatus; The first transmission line and It is a synchronous transmission path constituting the synchronous network Receiving with a receiving means capable of receiving from both of the second transmission paths;
When the connection confirmation frame is received from both the first and second transmission lines, the other transmission apparatus sends the first connection confirmation frame. 2 If the setting is made not to receive the data transferred through the other transmission path and the connection confirmation frame cannot be received from the other transmission apparatus through the first transmission path for a predetermined time, the second transmission path from the other transmission apparatus A reception control step for setting to receive data transferred through the transmission path.
[0014]
The fourth aspect of the present invention is: Connected to a synchronous network with other transmission devices A data reception control method for a transmission device,
The data including the source address An asynchronous transmission path constituting an asynchronous network connecting the other transmission apparatus and the transmission apparatus; Receive from the first transmission line, and Said The data given the address of another transmission device It is a synchronous transmission path constituting the synchronous network Receiving each of the data with a receiving means capable of receiving from the second transmission path;
When the data is received from both the first and second transmission paths, the first 2 If the data transferred through the transmission line is not received, and the data cannot be received through the first transmission line for a predetermined time, the data is transferred from the other transmission apparatus through the second transmission line. A reception control step for performing settings for receiving the data.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The configuration of the embodiment is an exemplification, and the present invention is not limited to the configuration of the embodiment.
[0016]
[Outline of Embodiment]
First, as an overview of an embodiment of the present invention, a network configuration that can solve the above-described problems will be described. FIG. 1 shows a synchronous network including a plurality of transmission apparatuses according to the present invention, and attempts to solve the problem by transmitting and receiving a connection confirmation frame between the transmission apparatuses.
[0017]
In the embodiment, a ring network (synchronous network) in which transmission apparatuses (for example, SDH transmission apparatuses: also referred to as “nodes” as necessary) are arranged in a ring shape is constructed. Each node accommodates an asynchronous network (eg Ethernet).
[0018]
A specific band is secured on a synchronous transmission line (for example, an optical transmission line) connecting each node, and each node sequentially sends out data frames to adjacent nodes by dropping in and dropping out data frames on the band. To do. Such a technique is disclosed in Japanese Patent Application No. 2000-333735 described above.
[0019]
Each node transmits and receives a data frame with its own node number assigned to the above-described band for a frame from the asynchronous network that it accommodates.
[0020]
For asynchronous networks that require a redundant configuration in addition to the synchronous transmission path between the nodes, the asynchronous networks are connected by an asynchronous line such as a LAN line, and a plurality of transmission paths are constructed between the asynchronous networks. That is, in the example shown in FIG. 1, a synchronous transmission path (second transmission path) passing through a synchronous network and an asynchronous transmission path (first transmission path) passing through an asynchronous line (LAN line) connecting the asynchronous networks. And have been built.
[0021]
Each node periodically transmits a node connection frame (also referred to as a “connection confirmation frame”) assigned with its own node number by broadcast to both the synchronous line and the asynchronous line. The node number is identification information of the transmission apparatus on the synchronous network, and is also called “node address”.
[0022]
Node connection frames sent to the synchronous line are sequentially dropped in and dropped out to adjacent nodes, and notified to all nodes on the synchronous network. On the other hand, the node connection frame sent to the asynchronous line accommodated by the node is notified to all terminals connected to the asynchronous line and all nodes connected via the asynchronous line.
[0023]
In the example shown in FIG. 1, a broadcast-designated node connection frame transmitted from the node 1 is forwarded, for example, clockwise in the synchronous transmission path (optical transmission path) and received by the nodes 2 to 6. The node connection frame is received by the node 2 from the asynchronous network (Ethernet E1) accommodated in the node 1 through the asynchronous network (Ethernet E2) accommodated in the node 2 through the asynchronous line (LAN line). That is, the node 2 can receive the node connection frame from the node 1 from both the synchronous line and the asynchronous line. Also, the node 1 can receive the broadcast designated node connection frame transmitted from the node 2 from both the synchronous line and the asynchronous line.
[0024]
Each node records the reception of a node connection frame for each synchronous / asynchronous line, and when receiving a node confirmation frame assigned the same node number from a plurality of lines, the data frame assigned the node number Is filtered from the synchronization line. For example, the reception logical port for the data from the designated node (the node having the same node number received from the synchronous and asynchronous lines) is updated so as not to be received.
[0025]
As a result, when the local node is connected to a certain node by an asynchronous line and a synchronous line, when the node connection frame of the node is received from both sides, the data frame of the node is received from the synchronous line. Disappear. Therefore, occurrence of a loop (double reception of the same data) can be prevented.
[0026]
For example, when the node connection frame from the node 1 is received from both the synchronous line and the asynchronous line, the node 2 is set not to receive the data frame of the node 1 from the synchronous line. Also, when the node 1 receives the node connection frame from the node 2 from both the synchronous line and the asynchronous line, the node 1 is set not to receive the data frame of the node 2 from the synchronous line.
[0027]
In addition, when a node connection frame cannot be received from an asynchronous line, each node waits for a certain period of time and updates the reception logical port on the synchronous line side of the node number that cannot be received from the asynchronous line side. To do.
[0028]
As a result, when the own node is connected to a certain node with an asynchronous line and a synchronous line, even if the reception of the data frame from the synchronous line is blocked (rejected), if an asynchronous line failure occurs, Reception of the data frame from the synchronous line is resumed. Therefore, data communication continues even if a failure occurs in the asynchronous line.
[0029]
For example, when the node connection frame from the node 1 cannot be received from the asynchronous line due to the failure of the asynchronous line, the node 2 switches to the setting for receiving the data frame of the node 1 from the synchronous line. On the other hand, when the node 1 cannot receive the node connection frame from the node 2 from the asynchronous line due to the failure of the asynchronous line, the node 1 switches to the setting for receiving the data frame of the node 2 from the synchronous line. As a result, the nodes 1 and 2 can continue to transmit and receive both data by switching the line.
[0030]
[First Embodiment]
Initially, the 1st Embodiment of this invention is described using FIGS. FIG. 2 is a diagram illustrating a configuration example of the transmission apparatus according to the first embodiment of the present invention, and FIG. 3 is a format explanatory diagram of a connection confirmation frame (B) received by the transmission apparatus according to the first embodiment. 4 is an explanatory diagram of the format of the connection confirmation frame (A) received by the transmission apparatus according to the first embodiment, and FIG. 5 shows an example of the data structure of the connection confirmation frame table shown in FIG. 6 is a flowchart showing the processing of the double reception check unit shown in FIG. 1, FIG. 7 is a diagram showing a configuration example of the receiving node address filter unit, and FIG. 8 is an aging process. FIG. 9 is a diagram illustrating a configuration example of a network to which the transmission apparatus according to the embodiment is applied.
[0031]
<overall structure>
FIG. 2 is a diagram illustrating a configuration example (overall configuration 1) of the transmission apparatus 10 according to the first embodiment. The transmission apparatus 10 is a digital transmission apparatus (SDH transmission apparatus) that functions as a node constituting a synchronous (optical) network as shown in FIG. 1, and is synchronized with an asynchronous transmission path (asynchronous line side (LAN side)). Connected to the transmission line (synchronous line side (optical line side)). The asynchronous transmission path indicates a line such as Ethernet and a transmission / reception unit for MAC frame data. The synchronous transmission line indicates a synchronous line such as an optical line.
[0032]
The transmission apparatus 10 includes an L2-SW unit 11, an asynchronous line connection confirmation frame extraction unit 12, a synchronous transmission line connection confirmation frame transmission unit 13, a synchronous transmission line transmission unit 14, and a synchronous transmission line reception unit 15. Line connection frame extraction unit 16, connection confirmation frame table 17, reception node address filter unit (reception address filter) 18, double reception check unit 19, aging processing unit 20, asynchronous transmission line connection confirmation frame transmission unit 21 is provided.
[0033]
The L2-SW unit 11 is a MAC switch that switches data to a synchronous transmission line side or an asynchronous transmission line side based on a destination MAC address (DA) of a MAC frame (data frame).
[0034]
The asynchronous line connection confirmation frame extraction unit 12 extracts the connection confirmation frame (A) received from the asynchronous line (asynchronous transmission path), and notifies the connection confirmation frame table 17 of the received node address and reception time. The asynchronous line connection confirmation frame extraction unit 12 sends other data frames to the synchronous transmission path sending unit 14.
[0035]
The synchronous transmission path connection confirmation frame sending unit 13 describes its own node address in the connection confirmation frame (B) and sends it to the synchronous transmission line sending unit 14 at regular intervals.
[0036]
The synchronous transmission path sending unit 14 outputs the data frame to the synchronous transmission path. The synchronous transmission path receiving unit 15 extracts data frames addressed to its own node address and broadcast from the synchronous transmission path, and sends them to the synchronous line connection confirmation frame extraction unit 16.
[0037]
The synchronous line connection confirmation frame extraction unit 16 extracts the connection confirmation frame (B) from the data frame and notifies the connection confirmation frame table 17 of the received node address and reception time. The synchronous line connection confirmation frame extraction unit 16 sends a data frame other than the connection confirmation frame (B) to the reception node address filter unit 18.
[0038]
In the connection confirmation frame table 17, the double reception check unit 19 checks whether a frame having the same node address is received from both synchronous / asynchronous lines, and sends data to the asynchronous line side for the same node address. A setting for not transferring (not receiving data from the synchronous line side) is set in the reception address filter 18.
[0039]
The reception address filter 18 constitutes a reception logical port for a data frame from the synchronous line side, and sends only data (frame) having a node address for which transfer is permitted to the asynchronous transmission path.
[0040]
The aging processing unit 20 periodically polls the connection confirmation frame table 17 and deletes the registration of the node address received from synchronous / asynchronous after a predetermined time has elapsed.
[0041]
The asynchronous transmission path connection confirmation frame sending unit 21 writes its own node address in the connection confirmation frame (A) and sends it to the asynchronous transmission path at regular intervals.
[0042]
<Type of connection confirmation frame>
FIG. 3 corresponds to the transmission apparatus 10 shown in FIG. 2, and is a connection confirmation frame (B) (second connection confirmation) transferred on the optical transmission path (synchronous transmission path) and transmitted / received between the nodes (transmission apparatuses). FIG.
[0043]
In FIG. 3, the connection confirmation frame (B) includes a transmission destination SDH transmission device number including the transmission destination node number, a transmission source SDH transmission device identification including the transmission source node number, and drop-in and drop-out between the optical transmission devices. It consists of a LIFE value that defines the number, a frame length for storing the frame length of the connection confirmation frame, a connection confirmation frame identification indicating that this frame is a connection confirmation frame, and an FCS (Frame Check Sequence).
[0044]
When each node transmits the connection confirmation frame (B), it defines the transmission as the transmission destination SDH transmission apparatus identification and transmits it. As a result, the connection confirmation frame (B) is dropped in and dropped out by all the nodes located on the ring of the synchronous network by one frame.
[0045]
FIG. 4 is a format explanatory diagram of a connection confirmation frame (A) (first connection confirmation frame) transmitted and received between nodes on an asynchronous transmission path. The connection confirmation frame (A) is provided by the MAC frame, and includes a transmission destination MAC address, a transmission source MAC address, a connection confirmation frame identification indicating that this frame is a connection confirmation frame, and a transmission source SDH transmission including the transmission source node number. Consists of device identification.
[0046]
When each node (transmission apparatus 10) transmits the connection confirmation frame (A), the broadcast is defined as the transmission destination MAC address and transmitted. As a result, the connection confirmation frame (A) is notified to all nodes on the synchronous transmission path by one frame.
[0047]
<Configuration of connection confirmation frame table>
FIG. 5 is a diagram illustrating a data structure example of the connection confirmation frame table 17 in the transmission apparatus 10 illustrated in FIG. The connection confirmation frame table 17 stores information (state information) related to the connection confirmation frame received from the synchronous line side and the asynchronous line side.
[0048]
Specifically, the connection confirmation frame table 17 includes a set of tables corresponding to the number of nodes (on the synchronous transmission path) connected to the synchronous network. Each table is specified by a node number.
[0049]
Each table stores a synchronous line node reception flag for storing a transmission / reception flag (reception / non-reception = ON / OFF) corresponding to the node number of the connection confirmation frame (B) received from the synchronous line side, and its reception time. Asynchronous line node reception flag for storing a transmission / reception flag (reception / non-reception = ON / OFF) corresponding to the node number of the connection confirmation frame (A) received from the asynchronous line, and its reception time Asynchronous line reception time for storing. When a connection confirmation frame is received from each of the synchronous and asynchronous lines, the corresponding node reception flag is set to ON.
[0050]
<Processing flow of double reception check unit>
FIG. 6 shows a processing flow of the double check unit 19 (node confirmation frame double reception check unit) that sets a reception address filter from the connection confirmation frame table. The process shown in FIG. 6 is started in the double reception check unit 19 at a constant cycle. However, it may be activated every time at least one of the connection confirmation frames (A) and (B) is received.
[0051]
In FIG. 6, when starting the process, the double reception check unit 19 determines in step S01 whether or not this process has been looped by the number of transmission apparatuses in the network (predetermined). At this time, if the process is not looped (S01; in the loop), the process proceeds to step S02. If the process is looped (S01; loop end), the process ends.
[0052]
In step S02, the double reception check unit 19 identifies one table to be processed, and whether or not both the synchronous line node reception flag and the asynchronous line node reception flag set in this table are ON. Determine. At this time, if both flags are on (S02; YES), the process proceeds to step S03, and if not (S02; NO), the process proceeds to step S04.
[0053]
In step S03, the double reception check unit 19 sets the reception address filter 18 to disable frame reception from the node having this node number, and returns the process to step S01.
[0054]
In step S04, the double reception check unit 19 determines whether or not the synchronous line node reception flag is ON and the asynchronous line node reception flag is OFF (OFF). At this time, if the synchronous line node reception flag is on and the asynchronous line node reception flag is off (S04; YES), the process proceeds to step S05. If not (S04; NO), the process proceeds to step S05. Proceed to S06.
[0055]
In step S05, the double reception check unit 19 sets the reception address filter 18 to enable frame reception from a node having this node number, and returns the process to step S01.
[0056]
In step S06, the double reception check unit 19 determines whether the synchronous line node reception flag is off and the asynchronous line node reception flag is on. At this time, if the synchronous line node reception flag is off and the asynchronous line node reception flag is on (S06; YES), the process proceeds to step S07. If not (S06; NO), the process proceeds to step S07. Proceed to S08.
[0057]
In step S07, the double reception check unit 19 sets the reception address filter 18 to disable reception from this node number, and returns the process to step S01.
[0058]
In step S08, the double reception check unit 19 sets the reception address filter 18 to disable reception from this node number, and returns the process to step S01.
[0059]
As described above, when both the synchronous and asynchronous line node reception flags are on for each node on the network, the double reception check unit 19 determines that the node number is the source node number for the reception address filter 18. Set to reject data frame passing (reception).
[0060]
In addition, when the synchronous line node reception flag is on and the asynchronous line node reception flag is off, the double reception check unit 19 sets the node number as the transmission source node number to the reception address filter 18. Set to allow passage (reception) of certain data frames.
[0061]
<Reception address filter configuration>
FIG. 7 shows a configuration example of the reception address filter 18. The reception address filter 18 performs a filtering process on the data frame received from the synchronous transmission path based on the setting by the double reception check unit 19. The reception address filter 18 includes a transmission source node address extraction unit 22, a node address reception permission table 23 (permission table 23), and a transmission / reception filter 24.
[0062]
The permission table 23 holds a state (disable (reject) / enable (permit)) set by the double reception check unit 19 for each node address (node number). The permission table 23 is updated by the process (FIG. 6) of the dual reception check unit 19 described above.
[0063]
When the data frame F transferred from the synchronous transmission path is input to the reception address filter 18, the transmission source node address extraction unit 22 extracts the transmission source node address (transmission source node number) from the data frame F, Contrast with permission table 23. At this time, if the state corresponding to the transmission source node address is set to reception on (enable), a reception permission instruction is given to the transmission / reception filter 24 from the permission table 23, and the transmission / reception filter 24 transmits the data frame F asynchronously. Transfer to the road. On the other hand, when the state corresponding to the transmission source node address is set to off (disabled), a reception rejection instruction is given from the permission table 23 to the transmission / reception filter 24, and the transmission / reception filter 24 transmits the data frame 24. No transfer to the asynchronous transmission path is performed (data frame F is discarded).
[0064]
As described above, the reception address filter 18 discards the data frame F when the reception flag is turned on on both the synchronous and asynchronous line sides, and the synchronous line side is on and the asynchronous line side is off. In this case, the data frame F is transmitted.
[0065]
That is, the reception address filter 18 blocks and opens the reception logical port on the synchronization line side of each node according to the setting of the permission table 23. This prevents the node from receiving the same data frame from both the synchronous line and the asynchronous line.
[0066]
<Processing flow of the aging processing section>
FIG. 8 is a flowchart showing processing by the aging processing unit 20. The process shown in FIG. 8 is started at a fixed cycle in the aging processing unit 20.
[0067]
When the process is started, the aging processing unit 20 determines whether or not the process has been looped by the number of tables constituting the connection confirmation frame table 17 in step S11. At this time, if the process is not looped (S11; in the loop), the process proceeds to step S12. If the process is looped (S11; loop end), the process by the aging processing unit 20 is completed. To do.
[0068]
In step S12, the aging processing unit 20 identifies one table from the connection confirmation frame table 17, and determines whether or not the difference between the synchronous line reception time set in this table and the current time is greater than or equal to a certain value. . At this time, if the difference is greater than or equal to a certain value (S12; YES), the process proceeds to step S13, and if not (S12; NO), the process proceeds to step S14.
[0069]
In step S13, the aging processing unit 20 deletes (sets off) the synchronous line node reception flag and initializes the synchronous line reception time. Thereafter, the process proceeds to step S14.
[0070]
In step S14, the aging processing unit 20 determines whether or not the difference between the asynchronous line reception time and the current time is greater than or equal to a certain value. At this time, if the difference is greater than or equal to a certain value (S14; YES), the process proceeds to step S15. If not (S14; NO), the process returns to step S11.
[0071]
In step S15, the aging processing unit 20 deletes (sets off) the asynchronous line node reception flag and initializes the asynchronous line reception time. Thereafter, the process returns to step S11.
[0072]
In this way, the aging processing unit 20 sets the corresponding reception flag to OFF when a predetermined time has elapsed since the connection confirmation frame was received. As a result, when a certain period of time has elapsed since the failure of the asynchronous line, the data frame receiving side can be switched from the asynchronous line side to the synchronous line side.
[0073]
<Operation example>
Next, an operation example of the transmission apparatus 10 in the synchronous network will be described. FIG. 9 is a diagram illustrating a construction example of a synchronous network (optical network) to which the transmission apparatus 10 is applied. A plurality of transmission apparatuses 10 are connected to the optical network. In the example shown in FIG. 9, three transmission apparatuses 10 are connected by an optical transmission line to construct a ring-shaped synchronous network.
[0074]
Each transmission device 10 secures a certain band (TS: Time Slot) on the optical transmission line, and each transmission device 10 drops in and drops out a data frame from this band, so that the data frame is relayed clockwise. Is done.
[0075]
In the example shown in FIG. 9, each transmission apparatus 10 has a node number, and numbers from 1 to 3 are set. Hereinafter, each transmission apparatus 10 may be referred to as a node 1, a node 2, or a node 3 as necessary.
[0076]
Each transmission device 10 accommodates an asynchronous network (Ethernet E1, E2, E3), and each Ethernet E1, E2, E3 accommodates terminals A to F. Each terminal A to F has a MAC address “a” to “f”, respectively.
[0077]
The asynchronous lines of the nodes 1 and 3 are connected by a LAN line (directly connected or via a bridge), and a redundant configuration with an optical line and a LAN line is constructed between the nodes 1-3.
[0078]
The operation of selecting an optical line and a LAN line between the node 1 and the node 3 in the construction example shown in FIG. 9 will be described with reference to FIG. The synchronous transmission path connection confirmation frame sending unit 13 of the node 1 periodically outputs a connection confirmation frame (B). The connection confirmation frame (B) is sent to the synchronous transmission line via the synchronous transmission line transmission unit 14.
[0079]
Further, the asynchronous transmission path connection confirmation frame sending unit 21 of the node 1 periodically outputs the connection confirmation frame (A). The connection confirmation frame (A) is sent to the asynchronous transmission path via the asynchronous transmission path transmission section of the node 1.
[0080]
The connection confirmation frame (B) output to the synchronous transmission path is notified to the node 2 via the optical line. After receiving the connection confirmation frame (B), the node 2 further transmits the connection confirmation frame (B) to the node 3.
[0081]
In the node 3, the synchronous transmission path receiving unit 15 receives the connection confirmation frame (B) from the synchronous transmission path and sends it to the synchronous line connection frame extracting unit 16.
[0082]
When the synchronous line connection frame extraction unit 16 recognizes that the input frame is the connection confirmation frame (B), it extracts the transmission source node number from the transmission source SDH transmission apparatus identification of the connection confirmation frame (B), The fact that the connection confirmation frame (B) from the node 1 is received is recorded in the synchronous line node reception flag (FIG. 5) of the connection confirmation frame table 17 corresponding to the transmission source node number (synchronous line node reception flag). Is set to ON and the reception time is registered).
[0083]
On the other hand, the connection confirmation frame (A) output from the node 1 to the asynchronous transmission line is received by the asynchronous transmission line receiver of the node 3 via the asynchronous transmission line (LAN line), and the asynchronous line connection confirmation frame is received. It is sent to the extraction unit 12.
[0084]
When the asynchronous line connection confirmation frame extraction unit 12 recognizes that the input frame is the connection confirmation frame (A), the asynchronous line connection confirmation frame extraction unit 12 extracts the transmission source node number from the transmission source SDH transmission apparatus identification of the connection confirmation frame (A). The fact that the connection frame (A) from the node 1 is received is recorded in the asynchronous line node reception flag (FIG. 5) of the connection confirmation frame table 17 corresponding to the transmission source node number (asynchronous line node reception flag). And set the reception time).
[0085]
In the node 3, every time the connection confirmation frame (A) and the connection confirmation frame (B) are received, the double reception check unit 19 performs processing according to the processing flow shown in FIG. On the other hand, whether to receive a data frame from the node 1 is set. In this example, since both flags corresponding to the connection confirmation frames (A) and (B) are turned on, the data frame reception of the node 1 from the synchronous line is not performed.
[0086]
Node 3 sends connection confirmation frames (A) and (B) in the same manner as node 1, and node 1 performs the same operation as node 3 described above. As a result, the node 1 does not receive the data frame of the node 3 from the synchronous line.
[0087]
Thereafter, when a broadcast-designated data frame is transmitted from the terminal A (MAC address “a”) accommodated in the node 1, the data frame is transferred to the nodes 2 and 3 via the synchronization line, and It is transferred to the node 3 via the asynchronous line. At this time, the node 3 refuses reception of the data frame from the node 1 on the synchronous line. Therefore, the node 3 does not need to receive the data frame from the node 1 twice.
[0088]
Further, since the transfer of the data frame is stopped by the reception address filter 18, it is possible to prevent the MAC frame in the data frame from being sent out from the node 3 to the asynchronous transmission path.
[0089]
In the above operation example, when the asynchronous line (LAN line) between the node 1 and the node 3 is disconnected, the node 3 receives the connection confirmation frame (A) of the node 1 from the asynchronous transmission line for a certain time or more. become unable. In this case, the aging processing unit 20 of the node 3 sets the corresponding asynchronous line node reception flag to OFF according to the processing flow shown in FIG. As a result, the asynchronous line node reception flag (connection confirmation frame (A)) corresponding to node 1 is turned off and the synchronous line node reception flag (connection confirmation frame (B)) is turned on.
[0090]
Then, the double reception check unit 19 performs setting for permitting reception of the data frame of the node 1 from the synchronous line to the reception address filter 18. As a result, the node 3 receives the data frame of the node 1 from the synchronous line and sends it out to the asynchronous transmission line.
[0091]
In this way, the node 3 receives the data frame from the terminal accommodated in the node 1 via the asynchronous line when the asynchronous line and the synchronous line are normal, and when the asynchronous line is abnormal, It can be received via a synchronous line.
[0092]
Therefore, when the asynchronous transmission path is abnormal, the data frame from the terminal A reaches the node 3 through the synchronous transmission path, and the node 3 sends the data frame to the Ethernet E3. As a result, the data frame from the terminal A can reach the terminal C and / or the terminal D connected to the Ethernet E3.
[0093]
<effect>
According to the transmission device 10 and the synchronous network constructed by applying the transmission device 10 according to the first embodiment, in a ring-shaped synchronous network to which a plurality of transmission devices 10 are connected, between any transmission devices 10 ( For example, it is possible to construct a redundant configuration in which data transmission / reception is performed on one of the synchronous transmission path and the asynchronous transmission path by connecting the transmission apparatuses facing each other through an asynchronous transmission path.
[0094]
In addition, unlike the prior art, since STP is not used, a large number of confirmation frames are not sent to the synchronous network. Therefore, it is possible to prevent the bandwidth of the synchronous transmission path from being wasted due to the construction of the redundant configuration, thereby causing congestion.
[0095]
Further, according to the first embodiment, the following advantages can be obtained.
[0096]
(1) Cost
It is possible to suppress network congestion that occurs when a redundant line is built on the asynchronous line side in a large-scale LAN via an optical transmission line, or when a network is connected by mistake. This makes it easy to construct a network. Further, it is not necessary to install a router, a bridge, etc., and a network can be constructed at a low cost.
[0097]
(2) Performance
Even when a large number of nodes are connected, data frames for periodic communication confirmation for all nodes can be reduced by STP or the like, and the line bandwidth can be used efficiently.
[0098]
[Embodiment 2]
Next, a second embodiment of the present invention will be described with reference to FIGS. However, since the second embodiment has a portion common to the first embodiment, the common portion will be described with reference to FIGS.
[0099]
10 is a diagram showing a configuration example of a transmission apparatus according to the second embodiment of the present invention, FIG. 11 is a diagram showing a data structure example of the MAC node address correspondence table 17A shown in FIG. FIG. 12 is a flowchart showing processing of the dual reception check unit 19A shown in FIG. 10, and FIG. 13 is a flowchart showing processing of the aging processing unit 20A shown in FIG.
[0100]
<Constitution>
FIG. 8 is a diagram illustrating a configuration example (overall configuration 2) of the transmission apparatus 30 according to the second embodiment. Since the transmission device 30 has the same components as the transmission device 10, the same components will be described with the same reference numerals.
[0101]
Similar to the transmission device 10, the transmission device 30 is connected to the asynchronous transmission line and the synchronous transmission line. The asynchronous transmission line indicates a line such as Ethernet and a MAC frame data transmission / reception unit. The synchronous transmission line indicates a synchronous line such as an optical line.
[0102]
The transmission device 30 includes an L2-SW unit 11, a MAC address extraction unit 12A, a synchronous transmission path transmission unit 14, a synchronous transmission path reception unit 15, a MAC learning unit 16A, a MAC node address correspondence table 17A, and a reception A node address filter unit (reception address filter) 18, a double reception check unit 19, and an aging processing unit 20 are provided.
[0103]
The L2-SW unit 11 is a MAC switch that switches data to the synchronous transmission line side or the asynchronous transmission line side based on the transmission destination MAC address (DA) of the MAC frame.
[0104]
The MAC address extraction unit 12A extracts a source MAC address (SA) from a MAC frame received from an asynchronous line (asynchronous transmission path), and notifies the MAC node address correspondence table 17A of the received MAC address and reception time. . Further, the MAC address extracting unit 12A sends the MAC frame to the synchronous transmission path sending unit 14.
[0105]
The synchronous transmission path sending unit 14 adds its own node address to the MAC frame and outputs it to the synchronous transmission path. The synchronous transmission path receiving unit 15 extracts data frames addressed to its own node address and broadcast from the synchronous transmission path, and sends them to the MAC learning unit 16A and the reception address filter 18.
[0106]
The MAC learning unit 16A extracts a transmission source node address (transmission source node number) and a transmission source MAC address from the data frame, and receives the received transmission source node address, transmission source MAC address, and reception time in the MAC node address correspondence table 17A. Notice.
[0107]
The double reception check unit 19A checks whether the same MAC address is received from both synchronous / asynchronous lines in the MAC node address correspondence table 17A, and if there is the same MAC address, the corresponding node address Is set in the reception address filter 18 so as not to transfer the data having the above to the asynchronous line side (reject reception).
[0108]
The reception address filter 18 sends only data (frame) having a node address for which transfer is permitted to the asynchronous transmission path.
[0109]
The aging processing unit 20A periodically polls the MAC node address correspondence table 17A and deletes the registration of the node address received from synchronous / asynchronous after a predetermined time has elapsed.
[0110]
<Form of MAC node address correspondence table>
FIG. 11 shows the MAC node address correspondence table 17A shown in FIG. The MAC node address correspondence table 17 stores MAC addresses extracted from data frames received from synchronous lines and asynchronous lines.
[0111]
The MAC node address correspondence table 17A is composed of a plurality of tables prepared for each node constituting the synchronous network (in units of node numbers). Each table includes one or more entries prepared for each synchronization node MAC address. Each entry is extracted from the synchronous node MAC address for storing the source MAC address extracted from the data frame received from the synchronous line, the synchronous line reception time for storing the reception time, and the data frame received from the asynchronous line. Is set to ON when the source MAC address matches the synchronous node MAC address, and this ON state stores the asynchronous reception MAC address flag indicating reception from both synchronous and asynchronous lines and the reception time of the data frame The asynchronous line reception time to be stored.
[0112]
Note that the update processing of the MAC node address correspondence table 17A can be performed by the MAC address extraction unit 12A and the MAC learning unit 16A.
[0113]
<Processing flow of MAC double reception check unit>
FIG. 12 shows a processing flow of the MAC double reception check unit (double reception check unit 19A) for setting the reception address filter from the MAC node address correspondence table 17A. The process shown in FIG. 12 is periodically started at regular time intervals. However, it may be activated each time a frame is received on at least one of the synchronous / asynchronous line side.
[0114]
In FIG. 12, when the double reception check unit 19A starts processing, in step S21, the MAC node address correspondence table 17A is referred to, and whether or not the processing loops by the number of transmission devices (nodes) on the synchronous network. (Whether or not the processing for all the tables corresponding to each node number has been completed). At this time, if the process is not looped (S21; in the loop), the process proceeds to step S22. If the process is looped (S21; loop end), the process of the double reception check unit 19A is performed. Ends.
[0115]
In step S22, the double reception check unit 19A identifies one node number, and whether or not the process for the table corresponding to this node number has been looped by the number of synchronous node MAC addresses stored in the table (node number). Whether or not the processing for all entries in the table corresponding to is completed. At this time, if the process is not looped (S22; in the loop), the process proceeds to step S23. If not (S22; loop end), the process proceeds to step S25.
[0116]
In step S23, the double reception check unit 19A identifies one entry in the table, and determines whether or not the asynchronous reception MAC address flag in this entry is set to ON. At this time, if the asynchronous reception MAC address flag is set to ON (S23; ON), the process proceeds to step S24. If not (S23; OFF), the process returns to step S22.
[0117]
In step S24, the double reception check unit 19A sets the enable / disable setting corresponding to the node number to “disable” for the reception address filter 18. Thereafter, the process returns to step S22, and the process of step S23 is performed on all entries in the table.
[0118]
In this way, the process of step S23 is performed for all entries in the table, and if the asynchronous reception MAC address flag of any entry is on, the setting of the reception address filter 18 for that node number is set. Is disabled.
[0119]
In step S25, the double reception check unit 19A determines whether or not the asynchronous reception MAC address flag set in all entries in the table is off. At this time, if all the asynchronous reception MAC address flags are off (S25; YES), the process proceeds to step S26. If not (S25; NO), the process for the next table (node number) is performed. Therefore, the process returns to step S21.
[0120]
In step S26, the double reception check unit 19A sets the enable / disable setting corresponding to the node number to “enable” for the reception address filter 18. Thereafter, in order to perform processing for the next table (node number), the processing returns to step S21.
[0121]
As described above, when all the asynchronous reception MAC address flags in the table corresponding to a certain node number are OFF, it is assumed that the data frame cannot be received from the node through the asynchronous line. In order to receive the data frame from “1”, “enable” is set to the reception address filter 18.
[0122]
<Reception address filter configuration>
The configuration of the reception address filter 18 in the second embodiment is the same as that of the first embodiment (see FIG. 7).
[0123]
That is, when the data frame F transferred from the synchronous transmission path is input to the reception address filter 18, the transmission source node address extraction unit 22 extracts the transmission source node address from the data frame F, and Contrast. At this time, if the state corresponding to the transmission source node address is set to reception on (enable), a reception permission instruction is given to the transmission / reception filter 24 from the permission table 23, and the transmission / reception filter 24 transmits the data frame F asynchronously. Transfer to the road. On the other hand, when the state corresponding to the transmission source node address is set to reception off (disabled), a reception rejection instruction is given from the permission table 23 to the transmission / reception filter 24, and the transmission / reception filter 24 transmits the data frame 24. Are not transferred to the asynchronous transmission path (data frame F is discarded).
[0124]
<Processing flow of the aging processing section>
FIG. 13 is a flowchart showing processing by the aging processing unit 20A. The process shown in FIG. 13 is started at a constant cycle in the aging processing unit 20A.
[0125]
When the process starts, the aging processing unit 20A determines in step S211 whether or not the process has been looped by the number of tables in the MAC node address correspondence table 17A. At this time, if the process is not looped (S211; in the loop), the process proceeds to step S212, and if the process is looped (S211; loop end), the process by the aging processing unit 20A is terminated. To do.
[0126]
In step S212, the aging processing unit 20A identifies one table from the MAC node address correspondence table 17A, and determines whether or not the difference between the synchronous line reception time set in this table and the current time is a certain value or more. To do. At this time, if the difference is greater than or equal to a certain value (S212; YES), the process proceeds to step S213, and if not (S212; NO), the process proceeds to step S214.
[0127]
In step S213, the aging processing unit 20A deletes the synchronization node MAC address and initializes the synchronization line reception time. Thereafter, the process proceeds to step S214.
[0128]
In step S214, the aging processing unit 20A determines whether or not the difference between the asynchronous line reception time set in this table and the current time is equal to or greater than a certain value. At this time, if the difference is greater than or equal to a certain value (S214; YES), the process proceeds to step S215. If not (S214; NO), the process returns to step S211.
[0129]
In step S215, the aging processing unit 20A deletes (sets off) the asynchronous reception MAC address flag in the table and initializes the asynchronous line reception time. Thereafter, the process returns to step S211.
[0130]
As described above, the aging processing unit 20A deletes the corresponding synchronous node MAC address or turns off the asynchronous reception MAC address flag when a predetermined time has elapsed since the data frame was received. As a result, when a certain period of time has elapsed since the failure of the asynchronous line, the data frame receiving side can be switched from the asynchronous line side to the synchronous line side.
[0131]
In the configuration of the transmission apparatus 30 described above, whether or not to receive a frame on the synchronization line side is executed in units of node numbers, but it is configured such that whether or not to receive a frame is executed for each source MAC address. Also good.
[0132]
<Operation example>
The transmission apparatus 30 can be applied as the nodes 1, 2 and 3 in the network as shown in FIG. When the nodes 1, 2 and 3 shown in FIG. 9 are transmission apparatuses 30, the operation of selecting a synchronous line (optical line) and an asynchronous line (LAN line) between the node 1 and the node 3 is shown in FIG. Will be described.
[0133]
When the node 1 (transmission device 30) receives the MAC frame (source MAC address: a) from the terminal A from the asynchronous data receiving unit in the asynchronous transmission path, the MAC frame is transmitted via the L2-SW unit 11 to the MAC. It is sent to the address extraction unit 12A.
[0134]
The MAC address extraction unit 12A extracts the source MAC address from the MAC frame, and notifies the MAC node address correspondence table 17A of the source MAC address and the reception time. Further, the MAC address extracting unit 12A sends the MAC frame to the synchronous transmission path sending unit 14.
[0135]
The synchronous transmission path sending unit 14 adds the node address (node number) of the node 1 to the MAC frame and outputs it as a data frame to the synchronous transmission path. The data frame to which the node address of the node 1 is added is received by the synchronous transmission path receiving unit 15 of the node 3 after passing through the node 2.
[0136]
The synchronous transmission path receiving unit 15 extracts a data frame addressed to its own node address from the data frame received from the synchronous transmission path, and sends the data frame to the MAC learning unit 16A and the reception address filter 18.
[0137]
The MAC learning unit (MAC address learning unit) 16A extracts the node address of the node 1 that is the transmission source node address and the transmission source MAC address (a) from the data frame, and sets them in the MAC node address correspondence table 17. That is, the MAC learning unit 16A specifies a table having the node address (node number) of the node 1 from the MAC node address correspondence table 17A, and sets the transmission source MAC address (a) for one of the entries in the table. While setting as the synchronous node MAC address, the reception time is set as the synchronous line reception time.
[0138]
On the other hand, the MAC frame from the terminal A is transferred to the node 3 through an asynchronous line (LAN line). The node 3 receives this MAC frame from the asynchronous transmission path and inputs it to the MAC address extraction unit 12A.
[0139]
Then, the MAC address extracting unit 12A extracts the SA (source MAC address) of the MAC frame, and notifies the MAC node address correspondence table 17A of the source MAC address together with the reception time. At this time, an entry in which the same MAC address as the source MAC address is set as the synchronous node MAC address is searched, and when such an entry is found, the asynchronous reception MAC address flag in the entry is switched from OFF to ON, The reception time is set as the asynchronous line reception time.
[0140]
In the node 3, every time the MAC frame is received, the double reception check unit 19A sets whether or not to receive the data frame from the node 1 to the reception address filter according to the processing flow shown in FIG. In this operation example, data frames having the same source MAC address are received from both the synchronous transmission path and the asynchronous transmission path. Therefore, the data frame from the node 1 is set not to be received from the synchronous line.
[0141]
The operation described above is also performed in the node 1, and the node 1 does not receive the data frame from the node 3 from the synchronous line.
[0142]
In this way, the MAC frame transmitted from the terminal A accommodated in the node 1 is transmitted to the nodes 2 and 3 via the synchronous line and to the node 3 via the asynchronous line. However, node 3 refuses to receive node 1's data frame from the synchronization line. For this reason, the data frame from the node 1 is not received twice.
[0143]
Thereafter, when the asynchronous line between the node 1 and the node 3 is disconnected, the node 3 cannot receive the MAC frame from the node 1 from the asynchronous transmission path. When this state continues for a predetermined time or longer, the aging processing unit executes the processing flow shown in FIG. 13 and sets the corresponding asynchronous reception MAC address flag to OFF. Then, the duplex reception check unit 19A executes the processing flow shown in FIG. As a result, the node 3 receives the data frame from the node 1 from the synchronous transmission path and sends it out to the asynchronous transmission path.
[0144]
As a result, when an abnormality occurs in the asynchronous line (LAN line), the MAC frame from the terminal A arrives at the node 3 through the synchronous transmission path and is sent from the node 3 to the Ethernet E3. In this way, the MAC frame from the terminal A can be delivered to the terminals C and / or D connected to the Ethernet E3 even if there is an abnormality in the LAN line.
[0145]
<effect>
The second embodiment can obtain the same effects as those of the first embodiment. However, since the connection confirmation frame is not used in the second embodiment, the bandwidth of the synchronous transmission path and the asynchronous transmission path can be used effectively. In addition, the configuration of the transmission apparatus can be simplified.
[0146]
[Others]
The above-described embodiments disclose the following invention. The inventions listed below can be combined as necessary.
(Supplementary Note 1) Receiving means capable of receiving a connection confirmation frame including the address of the transmission apparatus periodically transmitted from another transmission apparatus from both the first transmission path and the second transmission path;
If the connection confirmation frame is received from both the first and second transmission paths, a setting is made not to receive data transferred from the other transmission apparatus through the first transmission path, and the other A reception control means for setting to receive data transferred from the other transmission device through the second transmission line when the connection confirmation frame cannot be received from the transmission apparatus through the first transmission line for a predetermined time. When
Including transmission equipment. (1)
(Additional remark 2) When the said other transmission apparatus is provided with the said receiving means and the said reception control means, the said other transmission apparatus periodically transmits the connection confirmation frame containing an own address through the said 1st and 2nd transmission line. Further includes a transmitting means for transmitting to
The transmission apparatus according to appendix 1. (2)
(Supplementary Note 3) The reception control means includes:
A storage unit for storing state information indicating whether or not a connection confirmation frame has been received from each of the first and second transmission paths;
Referring to the state information, if the state information indicates that a connection confirmation frame has been received from both the first and second transmission lines, the other transmission transferred through the second transmission line. When the reception logical port for data from the device is blocked and the status information indicates that no connection confirmation frame has been received from the first transmission path and that a connection confirmation frame has been received from the second transmission path Includes a reception check unit that opens the reception logical port.
The transmission apparatus according to appendix 1 or 2.
(Supplementary Note 4) The reception control means includes:
A storage unit for storing status information indicating presence / absence of reception of a connection confirmation frame from each of the first and second transmission paths, and a reception time of each connection confirmation frame;
An update unit that refers to each reception time and sets the corresponding state information to no reception when the reception time has passed a predetermined time; and
Referring to the state information, if the state information indicates that a connection confirmation frame has been received from both the first and second transmission lines, the other transmission transferred through the second transmission line. When the reception logical port for receiving data from the device is blocked and the status information indicates that no connection confirmation frame has been received from the first transmission path and that a connection confirmation frame has been received from the second transmission path Includes a reception check unit that opens the reception logical port.
The transmission apparatus according to appendix 1 or 2.
(Additional remark 5) The receiving means which can receive the data containing a transmission source address from a 1st transmission line, and can receive the said data to which the address of the other transmission apparatus was provided from a 2nd transmission line,
If the data is received from both the first and second transmission paths, the data transferred through the first transmission path is set not to be received, and the first transmission path is set for a predetermined time. Receiving control means for setting to receive the data transferred from the other transmission device through the second transmission path when the data cannot be received through the second transmission path;
Including transmission equipment. (3)
(Additional remark 6) When the said other transmission apparatus is provided with the said receiving means and the said reception control means, while transmitting the data containing a transmission source address to the said other transmission apparatus through the said 1st transmission line, its own address Further includes transmission means for transmitting the data to which the data has been assigned to the other transmission device through the second transmission path.
The transmission apparatus according to appendix 5.
(Appendix 7) The reception control means includes
A storage unit for storing state information indicating whether or not the data is received from each of the first and second transmission lines;
With reference to the state information, when the state information indicates that the data has been received from both the first and second transmission lines, the other transmission device transferred through the second transmission line When the reception logical port of the data from the network is blocked and the status information indicates that no connection confirmation frame has been received from the first transmission path and that a connection confirmation frame has been received from the second transmission path Includes a reception check unit that opens the reception logical port.
The transmission apparatus according to appendix 5 or 6.
(Supplementary Note 8) The reception control means includes:
A storage unit that stores status information indicating whether or not the data is received from each of the first and second transmission paths, and a reception time of the data from the first transmission path;
An update unit that refers to the reception time and sets the corresponding state information to no reception when the reception time has passed a predetermined time; and
With reference to the state information, when the state information indicates that the data has been received from both the first and second transmission lines, the other transmission device transferred through the second transmission line The data reception logical port from the network is blocked, and the status information indicates that the data has not been received from the first transmission path and that the data has been received from the second transmission path. Includes a reception check unit that opens the reception logical port.
The transmission apparatus according to appendix 5 or 6.
(Supplementary Note 9) Step of receiving a connection confirmation frame periodically transmitted from another transmission apparatus and including an address of the transmission apparatus by receiving means capable of receiving from both the first transmission path and the second transmission path When,
If the connection confirmation frame is received from both the first and second transmission paths, a setting is made so that data transferred from the other transmission apparatus through the first transmission path is not received. A reception control step for setting to receive data transferred from the other transmission device through the second transmission path when the connection confirmation frame cannot be received from the transmission apparatus through the first transmission path for a predetermined time. When
A data reception control method for a transmission apparatus including: (4)
(Additional remark 10) When the said other transmission apparatus is provided with the said receiving means and the said reception control means, the said other transmission apparatus periodically transmits the connection confirmation frame containing an own address through the said 1st and 2nd transmission line. Further includes a sending step to send to
A data reception control method for a transmission apparatus according to appendix 9.
(Supplementary Note 11) The reception control step includes:
Storing status information indicating whether or not a connection confirmation frame has been received from each of the first and second transmission paths in a storage unit;
Referring to the state information, if the state information indicates that a connection confirmation frame has been received from both the first and second transmission lines, the other transmission transferred through the second transmission line. When the reception logical port for receiving data from the device is blocked, and the status information indicates that no connection confirmation frame has been received from the first transmission path and that a connection confirmation frame has been received from the second transmission path Includes the step of opening the reception logical port.
A data reception control method for a transmission apparatus according to appendix 9 or 10.
(Supplementary Note 12) The reception control step includes:
Storing status information indicating whether or not a connection confirmation frame has been received from each of the first and second transmission paths and the reception time of each connection confirmation frame in a storage unit;
Referring to each reception time, and setting the corresponding status information to no reception when the reception time has passed a predetermined time; and
Referring to the state information, if the state information indicates that a connection confirmation frame has been received from both the first and second transmission lines, the other transmission transferred through the second transmission line. When the reception logical port for receiving data from the device is blocked, and the status information indicates that no connection confirmation frame has been received from the first transmission path and that a connection confirmation frame has been received from the second transmission path Includes the step of opening the reception logical port.
A data reception control method for a transmission apparatus according to appendix 9 or 10.
(Supplementary note 13) The data including a transmission source address can be received from the first transmission path, and the data to which the address of another transmission apparatus is given can be received from the second transmission path by the receiving unit. Receiving each of
If the data is received from both the first and second transmission paths, a setting is made not to receive the data transferred through the first transmission path, and the first transmission path is set for a predetermined time. A reception control step for setting to receive the data transferred from the other transmission device through the second transmission path when the data cannot be received through
A data reception control method for a transmission apparatus including: (5)
(Additional remark 14) When the said other transmission apparatus is provided with the said receiving means and the said reception control means, while transmitting the data containing a transmission source address to the said other transmission apparatus through the said 1st transmission line, its own address Further including a transmission step of transmitting the data to which the data has been assigned to the other transmission device through the second transmission path.
15. A data reception control method for a transmission apparatus according to attachment 12.
(Supplementary Note 15) The reception control step includes:
Storing state information indicating whether or not the data has been received from each of the first and second transmission paths in a storage unit;
With reference to the state information, when the state information indicates that the data has been received from both the first and second transmission lines, the other transmission device transferred through the second transmission line When the reception logical port of the data from the network is blocked and the status information indicates that no connection confirmation frame has been received from the first transmission path and that a connection confirmation frame has been received from the second transmission path Includes the step of opening the reception logical port.
14. A data reception control method for a transmission apparatus according to appendix 12 or 13.
(Supplementary Note 16) The reception control step includes:
Storing status information indicating whether or not the data has been received from each of the first and second transmission paths and a reception time of the data from the first transmission path in a storage unit;
Referring to the reception time, and setting the corresponding state information to no reception when the reception time has passed a predetermined time; and
With reference to the state information, when the state information indicates that the data has been received from both the first and second transmission lines, the other transmission device transferred through the second transmission line The data reception logical port from the network is blocked, and the status information indicates that the data has not been received from the first transmission path and that the data has been received from the second transmission path. Includes opening the reception logical port.
14. A data reception control method for a transmission apparatus according to appendix 12 or 13.
[0147]
【The invention's effect】
According to the present invention, it is possible to construct a redundant configuration capable of receiving data from one of the first and second transmission paths with another transmission apparatus.
[0148]
In addition, according to the present invention, it is possible to suppress the occurrence of congestion in the second transmission path.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram of an embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration example of a transmission apparatus according to the first embodiment of the present invention.
FIG. 3 is an explanatory diagram of a format of a connection confirmation frame (B) received by the transmission apparatus according to the first embodiment.
FIG. 4 is an explanatory diagram of a format of a connection confirmation frame (A) received by the transmission apparatus according to the first embodiment.
FIG. 5 is a diagram illustrating an example of a data structure of the connection confirmation frame table illustrated in FIG. 2;
FIG. 6 is a flowchart illustrating processing of the double reception check unit illustrated in FIG. 2;
FIG. 7 is a diagram illustrating a configuration example of a receiving node address filter unit;
FIG. 8 is a flowchart illustrating processing of an aging processing unit.
FIG. 9 is a diagram illustrating a configuration example of a network to which the transmission apparatus according to the embodiment is applied.
FIG. 10 is a diagram illustrating a configuration example of a transmission apparatus according to a second embodiment of the present invention.
11 is a diagram illustrating an example of a data structure of the MAC node address correspondence table illustrated in FIG. 10;
FIG. 12 is a flowchart illustrating processing of the double reception check unit illustrated in FIG. 10;
FIG. 13 is a flowchart showing processing of an aging processing unit shown in FIG. 10;
FIG. 14 is a diagram illustrating a construction example of a network using the same band on an optical line.
FIG. 15 is a diagram illustrating an example of transmission path connection confirmation using STP;
[Explanation of symbols]
10,30 Transmission equipment (node)
11 L2-SW section
12 Asynchronous line connection confirmation frame extractor
12A MAC address extractor
13 Synchronous transmission line connection confirmation frame sending part
14 Synchronous transmission line sending part
15 Synchronous transmission line receiver
16 Sync line connection confirmation frame extractor
16A MAC learning unit
17 Connection confirmation frame table
17A MAC node address correspondence table
18 Receiving node address filter section
19,19A Double check part (Reception check part)
20,20A Aging processing section (update section)
21 Asynchronous transmission line connection confirmation frame sending part

Claims (5)

A transmission device connected to a synchronous network together with other transmission devices,
A first transmission that is an asynchronous transmission path that constitutes an asynchronous network that connects the other transmission device and the transmission device with a connection confirmation frame that is periodically transmitted from the other transmission device and includes the address of the transmission device. Receiving means capable of receiving from both of the second transmission path, which is a synchronous transmission path constituting the path and the synchronous network ;
Wherein when the connection confirmation frame is received from both of said first and second transmission line, to set not to receive the data transferred from the other transmission apparatuses through the second transmission path, said Reception control for setting to receive data transferred from the other transmission apparatus through the second transmission path when the connection confirmation frame cannot be received from the other transmission apparatus through the first transmission path for a predetermined time. Means for transmitting. When the other transmission apparatus includes the reception unit and the reception control unit, a transmission for periodically transmitting a connection confirmation frame including its own address to the other transmission apparatus through the first and second transmission paths. The transmission apparatus according to claim 1, further comprising means. A transmission device connected to a synchronous network together with other transmission devices,
Data including a transmission source address can be received from the first transmission path which is an asynchronous transmission path constituting the asynchronous network connecting the other transmission apparatus and the transmission apparatus, and the address of the other transmission apparatus is given. Receiving means capable of receiving the data from a second transmission line which is a synchronous transmission line constituting the synchronous network ;
When the data is received from both the first and second transmission paths, the data transferred through the second transmission path is set not to be received, and the first transmission path is set for a predetermined time. A transmission control unit configured to receive the data transferred from the other transmission device through the second transmission path when the data cannot be received through the transmission device. A data reception control method for a transmission device connected to a synchronous network together with other transmission devices,
A first transmission that is an asynchronous transmission path that constitutes an asynchronous network that connects the other transmission device and the transmission device with a connection confirmation frame that is periodically transmitted from the other transmission device and includes the address of the transmission device. Receiving with a receiving means receivable from both a path and a second transmission path which is a synchronous transmission path constituting the synchronous network ;
When the connection confirmation frame is received from both the first and second transmission paths, a setting is made not to receive data transferred from the other transmission apparatus through the second transmission path, and the other A reception control step for setting to receive data transferred from the other transmission device through the second transmission path when the connection confirmation frame cannot be received from the transmission apparatus through the first transmission path for a predetermined time. A data reception control method for a transmission apparatus. A data reception control method for a transmission device connected to a synchronous network together with other transmission devices,
Is receivable from the first transmission path are asynchronous transmission path constitutes an asynchronous network linking data, including the source address and the other transmission devices and the transmission device, and the address of the other transmission devices grant Receiving the data by receiving means capable of receiving the received data from a second transmission path that is a synchronous transmission path constituting the synchronous network ;
When the data is received from both the first and second transmission paths, the data transferred through the second transmission path is set not to be received, and the first transmission path is set for a predetermined time. If the data cannot be received through, a reception control step for setting to receive the data transferred from the other transmission device through the second transmission path;
A data reception control method for a transmission apparatus including:

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