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1. Field of the Invention
The present invention relates to a data transmission method and apparatus, and in particular to a protection method and apparatus for a data transmission to a communication carrier which provides wide-area LAN services or the like.
2. Description of the Related Art
In wide-area LAN services, corporate LANs are mainly connected, so that a main signal security or guarantee by a duplex mechanism is important. For attaining the main signal guarantee, a main signal redundant configuration such as an N:1 protection system or 1:1 protection system is adopted, so that communications are performed with a protection line even if a fault has occurred in a main line, thereby protecting the main signal and securing reliability of a data transmission. It is to be noted that in the following description, each of the main line and the protection line denotes a physical line.
1. N:1 Protection System: FIG. 28
In the above-mentioned N:1 protection system, a redundant configuration is formed with a single protection line for N sets of main lines. In the example of N=3 shown in FIG. 28, main lines L 1 -L 3 are connected to main line ports W 1 -W 3 of transmission apparatuses 200 ‘ 1 and 200 _ 2 , and a protection line L 4 is connected to protection line ports P 1 , thereby totally forming a transmission line L.
2. 1:1 Protection System: FIGS. 29-34
On the other hand, in the 1:1 protection system, a redundant configuration is formed with a single protection line for a single main line. In the example shown in FIG. 29, the main lines L 1 -L 3 are respectively connected to the main line ports W 1 -W 3 , and protection lines L 4 -L 6 are respectively connected to protection line ports P 1 -P 3 .
It is to be noted that in either system, the main line and the protection line are composed of lines with the same bandwidth.
Hereinafter, the 1:1 protection system will be described in more detail by referring to FIGS. 30-34.
2. 1. Arrangement: FIG. 30
FIG. 30 shows an arrangement of the transmission apparatuses 200 _ 1 and 200 _ 2 (hereinafter, occasionally represented by a reference numeral 200 ) in FIG. 29. The functions of the portions are as follows.
Reception Port Selector 1 :
The reception port selector 1 manages the information of a port which is presently valid within the main line/protection line ports (W 1 -W 3 and P 1 -P 3 ) of the redundant configuration, and transfers only a frame received at the valid port to a policing portion 2 . Accordingly, when a fault has occurred in the main line, a protection line which forms the redundant configuration with the main line is set as a valid port.
Policing Portion 2 :
The policing portion 2 performs policing, and transfers the frame to a switching portion 3 .
Switching Portion 3 :
The switching portion 3 determines a transmission port based on a destination MAC address of the frame, and transfers the frame to a shaper portion 5 _ 1 and a redundant frame transmitter 40 .
Redundant Frame Transmitter 40 :
The redundant frame transmitter 40 copies the frame, and transmits the copied frames from the main line port and the protection line port respectively through the shaper portions 5 _ 2 and 5 _ 3 .
Shaper Portion 5 ( 5 _ 1 and 5 _ 3 ):
The shaper portion 5 performs shaping and transmits the frame.
Command Accepting Portion 6 :
The command accepting portion 6 notifies, according to an input command, the information thereof to a redundant configuration manager 70 and the shaper portion 5 .
Redundant Configuration Manager 70 :
The redundant configuration manager 70 manages redundant configuration settings (setting contents) by the command input information with a redundant configuration management table TBL 1 , and notifies the redundant configuration settings to the reception port selector 1 and the redundant frame transmitter 40 .
It is to be noted that although a reception port and a transmission port without a redundant configuration are connected to the policing portion 2 and the shaper portion 5 _ 1 , they are not specifically related to the protection system of the present invention, so that the description of such ports will be omitted in the following description.
2. 2. Operation Example: FIGS. 31-34
Hereinafter, the operation of the portions will be described referring to FIGS. 31-34.
1) Frame Transmission from Protection Line Port: FIGS. 31 and 32
Firstly, the operation up to forming redundant configurations 1 - 3 by the transmission apparatus 200 _ 1 will be described referring to FIG. 31.
The command accepting portion 6 which has received a command for forming the redundant configuration 1 with a transmission port S 1 to the main line L 1 being made the main line port W 1 and a transmission port S 4 to the protection line L 4 being made the protection line port P 1 notifies settings to the redundant configuration manager 70 . The redundant configuration manager 70 notifies to the redundant frame transmitter 40 a redundant configuration No. 1 , the main line port S 1 , and the protection line port S 4 for the transmission port.
It is to be noted that while the redundant configuration manager 70 performs transmission port processing and reception port processing, only the transmission port processing will now be described for simplifying the description, where the reception port processing will be described in the following 2).
Similarly, the command accepting portion 6 receives commands for forming the redundant configuration 2 with a transmission port S 2 being made the main line port W 2 and the transmission port S 4 being made the protection line port P 2 , and the redundant configuration 3 with a transmission port S 3 being made the main line port W 3 and the transmission port S 4 being made the protection line port P 3 . The operation in this case is the same as the case of forming the redundant configuration 1 .
The case of transmitting a frame received at a reception port R 1 of the transmission apparatus 200 _ 1 shown in FIG. 31 from the main line port W 1 (transmission port S 1 ) and the protection line port P 1 (transmission port S 4 ) as the redundant configuration 1 will now be described.
The frame received at the reception port R 1 is transferred to the policing portion 2 . The policing portion 2 performs policing the frame to be transferred to the switching portion 3 . The switching portion 3 determines the transmission port S 1 (redundant configuration 1 ) based on the destination MAC address of the frame, and transfers the frame to the redundant frame transmitter 40 .
The redundant frame transmitter 40 copies the frame, and transfers the copied frames respectively to the shaper portion 5 _ 2 of the main line port W 1 (transmission port S 1 ) and the shaper portion 5 _ 3 of the protection line port P 1 (transmission port S 4 : protection line L 4 ). Then, the shaper portions 5 _ 2 and 5 _ 3 perform shaping the frames to be transmitted.
In the case of the transmission ports determined by the switching portion 3 being ports of the redundant configurations 2 and 3 , the copied frames are transmitted from the protection line ports P 2 (transmission port S 5 : protection line L 5 ) and P 3 (transmission port S 6 : protection line L 6 ) respectively as in the case of the redundant configuration 1 . FIG. 32 shows a frame transmission state at this time from all of the redundant configurations of the transmission apparatus 200 _ 1 .
2) Frame Reception at Protection Line Port: FIG. 33
Hereinafter, the operation up to forming the redundant configurations 1 - 3 by the transmission apparatus 200 _ 2 shown in FIG. 33 will be described.
The command accepting portion 6 having received a command for forming the redundant configuration 1 with the reception port R 1 being made the main line port W 1 and the reception port R 4 being made the protection line port P 1 notifies settings to the redundant configuration manager 70 . The redundant configuration manager 70 notifies to the reception port selector 1 the redundant configuration No. 1 , the main line port R 1 , and the protection line port R 4 , as to the reception port. While the redundant configuration manager 70 performs both of the transmission port processing and the reception port processing, only the reception port processing will now be described since the transmission port processing has been already described in the above-mentioned 1).
Similarly, the redundant configuration 2 is formed with the reception port R 2 as the main line port W 2 and with the reception port R 5 as the protection line port P 2 , and the redundant configuration 3 is formed with the reception port R 3 being made the main line port W 3 and the reception port R 6 being made the protection line port P 3 . The operation in this case is the same as the case of forming the redundant configuration 1 .
Hereinafter, an operation up to transmitting (transferring) the frame received at the main line port W 1 (reception port R 1 ) and the protection line port P 1 (reception port R 4 ) of the redundant configuration 1 of the transmission apparatus 200 _ 2 shown in FIG. 33 from the transmission port S 1 will be described.
As for the frame received at the main line port W 1 (reception port R 1 ), the reception port R 1 is notified to the reception port selector 1 of the redundant configuration 1 , and then the frame is transferred. Since the reception port notified is the reception port R 1 without a fault occurrence, the reception port selector 1 determines that the port is a current valid port of the redundant configuration 1 , and transfers the frame to the policing portion 2 . The policing portion 2 performs policing the frame to be transferred to the switching portion 3 . The switching portion 3 determines the transmission port S 1 based on the destination MAC address, and transfers the frame to the shaper portion 5 _ 2 of the transmission port S 1 . The shaper portion 5 _ 2 performs shaping the frame to be transmitted from the transmission port S 1 .
On the other hand, as for the frame received at the protection line port P 1 (reception port R 4 ), the reception port R 4 is notified to the reception port selector 1 of the redundant configuration 1 , and then the frame is transferred. Since having recognized that the valid reception port of the redundant configuration 1 is the reception port R 1 , the reception port selector 1 determines that the notified port is not the current valid port of the redundant configuration 1 since the notified reception port is the port R 4 , so that the frame is discarded.
3) Frame Reception Upon Fine fault: FIG. 34
Hereinafter, an operation up to transmitting the frame received at the protection line port P 1 (reception port R 4 ) from the transmission port 1 when a fault has occurred in the main line port W 1 (reception port R 1 ) of the redundant configuration 1 of the transmission apparatus 200 _ 2 shown in FIG. 34 will be described.
The frame received at the protection line port P 1 (reception port R 4 ) is transferred to the reception port selector 1 of the redundant configuration 1 . Having recognized that the valid reception port of the redundant configuration 1 is this time the reception port R 4 due to the line fault occurrence, the reception port selector 1 determines that the notified reception port 4 is the current valid port of the redundant configuration 1 , and transfers the frame to the policing portion 2 . The policing portion 2 performs policing the frame to be transferred to the switching portion 3 . The switching portion 3 determines the transmission port S 1 based on the destination MAC address of the frame, and transfers the frame to the shaper portion 5 _ 2 of the transmission port S 1 . The shaper portion 5 _ 2 performs shaping the frame to be transmitted from the transmission port.
Also in the cases of the protection line port P 2 (reception port R 5 ) of the redundant configuration 2 and the protection line port P 3 (reception port R 6 ) of the redundant configuration 3 , the reception port R 5 or R 6 is notified to the reception port selector 1 of the redundant configuration by the same operation as the case of the redundant configuration 1 , for transferring the frame. Since the notified port is the port R 5 or R 6 , the reception port selector 1 determines that neither port is the current valid port of the redundant configurations 2 or 3 , and discards the frame. FIG. 34 shows a frame reception state at this time.
It is to be noted that there are an ATM communication network and a fault restoration method by which a fault restoration message cell is transmitted from an incoming exchange and information is exchanged in an autonomous and distributed manner upon fault of the exchange, a network state is notified to a transmitting exchange, routes are switched over, and a route fault due to the fault of the exchange is restored by a VC route level (see e.g. patent document 1).
[Patent document 1] Japanese Patent Application Laid-open No. 9-18492
There have been problems in the prior art technologies as follows:
In lines forming the redundant configuration by the N:1 protection system, when a fault occurs in the main line W 2 in a state where the protection line P 1 is used due to the fault of the main line W 1 as shown in FIG. 35, the main signal of the main line W 2 can not be guaranteed since the protection line P 1 has been already used.
On the other hand, in lines forming the redundant configuration by the 1:1 protection system, when a fault occurs in the main line, the main line is always guaranteed by the protection line since the main line and the protection line exist in a 1:1 correspondence manner. However, while 10 main lines+a single protection line=11 lines are required for the N:1 protection system when a redundant configuration of e.g. 10 lines is desired to be formed, 10 main lines+10 protection lines=20 lines are required for the 1:1 protection system.
Thus, in the case of the N:1 protection system, it is impossible to switch all of the main lines. On the other hand, in the case of the 1:1 protection system which can switch all of the main lines, the protection lines for the number of protections are required, which leads to a problem that construction cost is increased.
It is accordingly an object of the present invention to provide a data transmission method and apparatus which can perform a switchover of all of the main lines without requiring much construction cost.
In order to achieve the above-mentioned object, a data transmission method (apparatus) according to the present invention comprises: a first step of (means) setting, as redundant configurations, combinations of a plurality of main lines with virtual paths established so as to include at least a part of a bandwidth of the main lines in one or more protection lines; and a second step of (means) copying frames received in the main lines and assigning identifiers of the redundant configurations to the copied frames to be transmitted through the virtual paths combined with the main lines in the redundant configurations.
Also, a data transmission method (apparatus) according to the present invention comprises: a first step of (means) setting, as redundant configurations, combinations of a plurality of main lines with virtual paths established so as to include at least a part of a bandwidth of the main lines in one or more protection lines; a second step of (means) determining whether the main lines or the virtual paths forming the redundant configurations are valid; a third step of (means) deleting identifiers of the redundant configurations assigned to frames received from the protection lines; and a fourth step of (means) determining whether the frames from which the identifiers have been deleted should be respectively discarded or transferred depending on validity or invalidity of the main lines.
The above-mentioned second step (means) may include a step of (means) rendering the main lines valid when no fault has occurred in the main lines, and rendering the virtual paths forming the redundant configurations with the main lines valid when a fault has occurred in the main lines.
Furthermore, the above-mentioned second step (means) may include a third step of (means) accepting redundant configuration setting including shaping rates in order that a total value of the shaping rates of main lines in redundant configurations using a same protection line does not exceed a bandwidth of the same protection line, and a fourth step of (means) performing shaping per redundant configuration according to the shaping rates accepted.
Furthermore, the above-mentioned third step (means) may include a step of (means) performing the redundant configuration setting for another protection line when the total value exceeds the bandwidth of the same protection line.
The above-mentioned identifiers comprise e.g. VLAN-IDs in VLAN Tags provided in the frames.
The above-mentioned concept will now be described referring to FIG. 1. The present invention adopts a protection system which secures main signals of main lines L 1 -L 3 with a single protection line L 4 between transmission apparatuses 100 _ 1 and 100 _ 2 (hereinafter, occasionally represented by a reference numeral 100 ). In the protection line L 4 , e.g. virtual paths V 1 -V 3 of bandwidths corresponding to the all of the main lines L 1 -L 3 are set, where it is only necessary to provide at least a single protection line, while in the presence of a plurality of protection lines, it is not necessary to set up all of the virtual paths corresponding to all of the main lines in a single protection line, so that insufficient virtual paths may be set up in other protection lines.
The combinations of e.g. the main lines L 1 -L 3 with the virtual paths V 1 -V 3 respectively are made redundant configurations, to which identifiers (IDs) are assigned. By assigning the identifiers to the frames transmitted from protection ports P 1 -P 3 , a plurality of virtual 1:1 protection transmission functions (i) can be obtained.
Also, the identifiers assigned in the frames received at the protection line ports P 1 -P 3 are deleted, and the redundant configurations are determined based on the identifiers, so that a plurality of virtual 1:1 protection reception functions (ii) can be obtained.
The data transmission method and apparatus according to the present invention will now be more briefly described by referring to FIGS. 2-7. It is to be noted that in the following description, the protection line port, the transmission port of the protection line (reception port of the protection line), and the virtual path are associated with each other in a 1:1 correspondence manner.
[1] Frame Transmission Operation by Redundant Configuration Setting: FIGS. 2 and 3
1) Firstly, an operation up to forming the redundant configurations 1 - 3 by the transmission apparatus 100 _ 1 shown in FIG. 2 will be described.
To form the redundant configuration 1 of the main line L 1 and the virtual path V 1 is set by a command input or the like with the transmission port S 1 being made the main line port W 1 (main line L 1 ) and the transmission port S 4 being made the protection line port P 1 (virtual path V 1 ). Based on the settings, transmission port processing and reception port processing are executed.
Similarly, the redundant configuration 2 of the main line L 2 and the virtual path V 2 with the transmission port S 2 being made the main line port W 2 and the transmission port S 4 as the protection line port P 2 , and the redundant configuration 3 of the main line L 3 and the virtual path V 3 with the transmission port S 3 being made the main line port W 3 and the transmission port S 4 being made the protection line port P 3 are formed as in the case of redundant configuration 1 .
2) Hereinafter, a case where a frame received at the reception port R 1 of the transmission apparatus 100 _ 1 shown in FIG. 2 is transmitted from the main line port W 1 (transmission port S 1 ) and the protection line port P 1 (transmission port S 4 ) of the redundant configuration 1 through the virtual path V 1 will be described.
As for the frame received at the reception port R 1 , the transmission port S 1 is determined based on a destination MAC address of the frame. When the frame is transmitted from the main line port W 1 (transmission port S 1 ) to the main line L 1 , the frame is copied, to which an identifier “a” of the redundant configuration 1 is assigned. The frame to which the identifier “a” is assigned is transmitted from the protection line port P 1 (transmission port S 4 ) through the virtual path V 1 of the protection line L 4 . FIG. 2 shows the frame transmission state at this moment.
Also in the cases of the transmission port of the redundant configurations 2 and 3 , as in the case of the redundant configuration 1 , frames to which identifiers “b” (redundant configuration 2 ) and “c” (redundant configuration 3 ) are assigned are respectively transmitted from the protection line ports P 2 and P 3 (transmission port S 4 ) through the virtual paths V 2 and V 3 . FIG. 3 shows the frame transmission state at this moment.
Thus, the identifier is assigned in the frame transmitted from the protection line, thereby enabling the frames of a plurality of redundant configurations to be transmitted with a single protection line.
[2] Frame Reception Operation by Redundant Configuration Setting: FIGS. 4 and 5
1) Firstly, an operation up to forming the redundant configurations 1 - 3 by the transmission apparatus 100 _ 2 shown in FIG. 4 will now be described.
To form the redundant configuration 1 of the main line L 1 and the virtual path V 1 is set by a command input or the like with the reception port R 1 being made the main line port W 1 and the reception port R 4 being made the protection line port P 1 . Based on the settings, the transmission port processing and the reception port processing are performed.
Similarly, the redundant configuration 2 of the main line L 2 and the virtual path V 2 with the reception port R 2 being made the main line port W 2 and the reception port R 4 being made the protection line port P 2 , and the redundant configuration 3 of the main line L 3 and the virtual path V 3 with the reception port R 3 being made the main line port W 3 and the reception port R 4 being made the protection line port P 3 are formed as in the case of redundant configuration 1 .
2) Hereinafter, an operation up to transmitting from the transmission port S 1 the frames received at the main line port W 1 (reception port R 1 ) and the protection line port P 1 (reception port R 4 ) of the redundant configuration 1 of the transmission apparatus 100 _ 2 shown in FIG. 4 in the absence of a line fault will be described.
As for the frame received at the main line port W 1 (reception port R 1 ), the identifier assigned thereto indicates the redundant configuration 1 , so that the reception port is R 1 . Therefore, determining that the reception port R 1 is a current valid port of the redundant configuration 1 , the transmission apparatus 100 _ 2 determines the transmission port S 1 based on the destination MAC address of the frame, so that the frame is transmitted from the transmission port S 1 .
On the other hand, as for the frame received at the protection line port P 1 (reception port R 4 ), the transmission apparatus 100 _ 2 acquires a redundant configuration No. 1 based on the identifier “a” assigned in the frame and deletes the identifier “a”.
Since the port notified at this moment is R 4 , it is determined that the reception port R 4 is not a current valid port of the redundant configuration 1 , so that the frame is discarded. FIG. 4 shows this frame reception state.
Thus, even if the identifier is assigned in the frame received at the protection line port in the absence of the line fault, the frame is normally discarded.
3) Hereinafter, an operation up to transmitting the frame received at the protection port P 1 (reception port R 4 ) from the transmission port S 1 during a fault occurrence in the main line port W 1 (reception port R 1 ) of the redundant configuration 1 of the transmission apparatus 100 _ 2 as shown in FIG. 5 will be described.
While the operation up to deleting the identifier of the frame received at the protection line port P 1 (reception port R 4 ) is the same as the operation already described in the above-mentioned 2), the main line port W 1 forming the redundant configuration 1 with the protection line port P 1 is in a fault state. Therefore, it is determined that the current valid port in the redundant configuration 1 is the protection line port P 1 to determine the transmission port S 1 based on the destination MAC address of the received frame, so that the frame is transmitted from the transmission port S 1 .
Thus, even if the identifier is assigned to the frame received at the protection line port, it is normally determined as a valid frame, so that reception processing is performed.
Also, in the cases of the protection line port P 2 of the redundant configuration 2 and the protection line port P 3 of the redundant configuration 3 (reception port R 4 in both cases), redundant configuration Nos. 2 and 3 are acquired respectively based on the identifiers “b” and “c” while the identifiers are deleted, as in the case of the redundant configuration 1 .
At this time, since the main line ports W 2 and W 3 forming the redundant configurations 2 and 3 respectively with the protection line ports P 2 and P 3 are normal without a fault occurrence, it is determined that the protection line ports P 2 and P 3 are not current valid ports of the redundant configurations 2 and 3 , so that the frames are discarded. FIG. 5 shows the frame reception state at this moment.
Thus, the redundant configuration No. is acquired based on the identifier assigned in the frame and the identifier is deleted, thereby enabling the frames of a plurality of redundant configurations to be received with a single protection line.
[3] QoS Guarantee in the Protection Line by the Redundant Configuration Setting
In the present invention, redundant configuration setting and shaping rate setting are accepted so that a total value of the shaping rates of the protection lines forming the redundant configuration with the main lines may not exceed a bandwidth of the protection lines, thereby providing a QoS guarantee in the protection line equivalent to that of the main line.
It is to be noted that since the operation other than the shaping rate setting is the same as the above-mentioned operation, the description thereof will be omitted hereinafter.
1) Firstly, an operation of the transmission apparatus 100 _ 1 up to forming the redundant configuration in the transmission line L between the transmission apparatuses 100 _ 1 and 100 _ 2 shown in FIG. 6 will now be described.
When the redundant configuration 1 is formed, to form the redundant configuration 1 with the transmission port S 1 being made the main line port W 1 and the transmission port S 4 being made the protection line port P 1 is set by a command input or the like.
Since there is not shown any other redundant configuration using the same protection line port S 4 in this example, a shaping rate A of the redundant configuration 1 is compared with a bandwidth X of the protection line port S 4 (protection line port L 4 ).
At this time, it is required to consider the above-mentioned identifier assigned to the frame upon transmitting the frame from the protection line port in order to provide the QoS guarantee in the protection line port equivalent to that of the main line port.
Namely, when the frame of the shaping rate A is transmitted from the main line port W 1 and an increase coefficient of the bandwidth having the identifier assigned thereto is α, a bandwidth of A*α is required for transmitting the frame to which the identifier is assigned from the protection line port P 1 . Accordingly, when the shaping rate is compared with the bandwidth of the protection line, it is required to determine whether or not the rate is the one which can be guaranteed by comparing “shaping rate*bandwidth increase coefficient=A*α” with “bandwidth of protection line=X”.
In the example of FIG. 6, the result of “A*α<X” is obtained, which can guarantee QoS. Therefore, the redundant configuration No. 1 , the protection line port S 4 , and the shaping rate A are registered.
When the redundant configuration 2 is formed, to form the redundant configuration 2 with the transmission port S 2 being made the main line port W 2 and the transmission port S 4 being made the protection line port P 2 is set by a command input or the like. The total value of the shaping rate A of the redundant configuration 1 using the same protection line port S 4 and a shaping rate B of the redundant configuration 2 is compared with the bandwidth X of the protection line port S 4 now to determine whether or not the rate can be guaranteed.
In the example of FIG. 6, the result of “shaping rate*bandwidth increase coefficient=(A+B)*α”<“bandwidth of protection line port=X” is obtained, which can guarantee the QoS. Therefore, the redundant configuration No. 2 , the protection line port S 4 , and the shaping rate B are registered.
When the redundant configuration 3 is formed, to form the redundant configuration 3 with the transmission port S 3 being made the main line port W 3 and the transmission port S 4 being made the protection line port P 3 is set by a command input or the like. The total value of the shaping rates (A+B) of the redundant configurations 1 and 2 using the same protection line port S 4 and a shaping rate C of the redundant configuration 3 is further compared with the bandwidth X of the protection line port S 4 now to determine whether or not the rate can be guaranteed. In the example of FIG. 6, the result of “shaping rate* bandwidth increase coefficient=(A+B+C)*α”>“bandwidth of protection line port=X” is obtained, so that the QoS can not be guaranteed, which leads to an error occurrence.
Thus, when the total value of the shaping rates of the redundant configurations which set the same transmission port as the protection line port exceeds the bandwidth of the protection line port, the redundant configuration can not be formed.
2) Hereinafter, an operation of the transmission apparatus 100 _ 1 up to changing the shaping rate of e.g. the redundant configuration 2 will be described as shown in FIG. 7.
When changing the shaping rate of the redundant configuration 2 to D is set by a command input or the like, the transmission apparatus 100 _ 1 compares the total value of the shaping rates except the shaping rate of the redundant configuration 2 (total A; shaping rate of the redundant configuration 1 ) and the shaping rate D after the change of the redundant configuration 2 with the bandwidth X of the protection line port S 4 to determine whether or not the rate can be guaranteed.
In the example of FIG. 7, the result of “shaping rate*bandwidth increase coefficient=(A+D)*α”<“bandwidth of protection line port=X” is obtained, which can guarantee the QoS. Therefore, the shaping rate of the redundant configuration No. 2 is updated to D.
Thus, when the total value of the shaping rates of the redundant configurations which set the same transmission port as the protection line port does not exceed the bandwidth of the protection line port even after forming the redundant configuration, the shaping rate can be changed.
Thus, redundant configuration setting and shaping rate setting are accepted so that a total value of the shaping rates of the redundant configurations which set the same transmission port as the protection line port does not exceed a bandwidth of the protection line. Thus, even if the identifier is assigned to the frame and transmitted from the protection line, a QoS guarantee equivalent to the main line in which no identifier is assigned to the frame can be provided.
The present invention can adopt physically N:1 configuration but logically 1:1 configuration. Therefore, it becomes possible to switch all of the main lines. Also, by physically making the protection line a single line, the reduction of the construction cost is made possible.
The above and other objects and advantages of the invention will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which the reference numerals refer to like parts throughout and in which:
FIG. 1 is a block diagram showing a principle of a data transmission method and apparatus according to the present invention;
FIG. 2 is a block diagram showing a frame transmission principle ( 1 ) of a data transmission method and apparatus according to the present invention;
FIG. 3 is a block diagram showing a frame transmission principle ( 2 ) of a data transmission method and apparatus according to the present invention;
FIG. 4 is a block diagram showing a frame reception principle ( 1 ) of a data transmission method and apparatus according to the present invention;
FIG. 5 is a block diagram showing a frame reception principle ( 2 ) of a data transmission method and apparatus according to the present invention;
FIG. 6 is a block diagram showing a QoS guarantee principle ( 1 ) of a data transmission method and apparatus according to the present invention;
FIG. 7 is a block diagram showing a QoS guarantee principle ( 2 ) of a data transmission method and apparatus according to the present invention;
FIG. 8 is a block diagram showing an embodiment (1) of a data transmission apparatus which executes a data transmission method according to the present invention;
FIG. 9 is a flowchart showing a processing example of a redundant frame transmitter in a data transmission apparatus according to the present invention;
FIG. 10 is a flowchart showing a processing example of a redundant configuration manager in a data transmission apparatus according to the present invention;
FIG. 11 is a flowchart showing a processing example of an ID deletion/transfer portion in a data transmission apparatus according to the present invention;
FIG. 12 is a flowchart showing a processing example of a redundant shaper portion in a data transmission apparatus according to the present invention;
FIGS. 13A and 13B are diagrams showing an example of a redundant configuration management table used for a data transmission apparatus according to the present invention;
FIGS. 14A-14E are diagrams showing an example of a received frame processing management table used for a data transmission apparatus according to the present invention;
FIG. 15 is a diagram showing a frame format used for a data transmission apparatus according to the present invention;
FIG. 16 is a block diagram showing an example of a network configuration by an embodiment (1) of the present invention;
FIG. 17 is a block diagram showing an example of a redundant configuration by an embodiment (1) of the present invention;
FIG. 18 is a block diagram showing an operation example (1) of a frame transmission by an embodiment (1) of the present invention;
FIG. 19 is a block diagram showing an operation example (2) of a frame transmission by an embodiment (1) of the present invention;
FIG. 20 is a block diagram showing an operation example (1) of a frame reception by an embodiment (1) of the present invention;
FIG. 21 is a block diagram showing an operation example (2) of a frame reception by an embodiment (1) of the present invention;
FIG. 22 is a block diagram showing an embodiment (2) of a data transmission apparatus according to the present invention;
FIG. 23 is a flowchart showing a processing example (1) (upon redundant configuration setting) of a shaper value calculating portion used for an embodiment (2) of the present invention;
FIG. 24 is a flowchart showing a processing example (2) (upon redundant configuration change) of a shaper value calculating portion used for an embodiment (2) of the present invention;
FIGS. 25A-25C are diagrams showing a shaping rate management table used for an embodiment (2) of the present invention;
FIG. 26 is a block diagram showing an example of a network configuration used for an embodiment (2) of the present invention;
FIG. 27 is a block diagram showing an example (1) redundant configuration setting of an embodiment (2) of the present invention;
FIG. 28 is a block diagram showing a prior art example (1) (N:1 protection system);
FIG. 29 is a block diagram showing a prior art example (2) (1:1 protection system);
FIG. 30 is a block diagram showing an arrangement of a prior art transmission apparatus (1:1 protection system);
FIG. 31 is a block diagram showing an operation example (1) of a prior art frame transmission;
FIG. 32 is a block diagram showing an operation example (2) of a prior art frame transmission;
FIG. 33 is a block diagram showing an operation example (1) of a prior art frame reception;
FIG. 34 is a block diagram showing an operation example (2) of a prior art frame reception; and
FIG. 35 is a block diagram showing a state of a fault occurrence in a plurality of lines of a prior art N:1 protection system.
FIG. 8 shows an arrangement of an embodiment (1) of the present invention, in which the same reference numerals as those in the prior art arrangement shown in FIG. 30 indicate the same portions. The different portions are as follows:
Redundant Configuration Frame Transmitter 4 :
The redundant configuration frame transmitter 4 copies a frame, and transmits the copied frames from the main line port and the protection line port. In the present invention, the frame is copied and identifiers are assigned to the copied frames. The original frame is transmitted from the main line port and the frame to which the identifier is assigned is transmitted from the protection line port. FIG. 9 is a flowchart showing a processing example of the redundant configuration frame transmitter 4 , which will be described later.
Redundant Configuration Manager 7 :
The redundant configuration manager 7 manages redundant configuration settings, and notifies redundant configuration settings to the reception port selector 1 and the redundant frame transmitter 4 . In the present invention, the redundant configuration manager 7 notifies the redundant configuration contents to the reception port selector 1 and the redundant frame transmitter 4 , as well as a processing mode of a received frame, a redundant configuration No., and an identifier to an ID deletion/transfer portion 8 . FIG. 10 shows the processing example of the redundant configuration manager 7 , which will be described later.
ID Deletion/Transfer Portion 8 ( 8 _ 1 - 8 _ 3 ):
When the processing mode of the received frame is “transfer”, the ID deletion/transfer portion 8 transfers the frame to each portion. When the processing mode of the received frame is “ID deletion”, the ID deletion/transfer portion 8 acquires the redundant configuration No. based on the identifier, and transfers the frame from which the identifier is deleted to the reception port selector 1 . FIG. 11 shows the processing example of the ID deletion/transfer portion 8 , which will be described later.
Redundant Shaper Portion 9 :
The redundant shaper portion 9 performs shaping per redundant configuration, and then transfers the frame to the redundant frame transmitter 4 . FIG. 12 shows a processing example of the redundant shaper portion 9 , which will be described later.
Also, in this embodiment (1), a received frame processing management table TBL 2 is used in addition to the redundant configuration management table TBL 1 . The redundant configuration management table TBL 1 is also used in the prior art example shown in FIG. 30, and is a table which manages a VLAN ID and the redundant configuration No. as shown in FIGS. 13A and 13B. The received frame processing management table TBL 2 is, as shown in FIGS. 14A-14E, a table associating the processing mode of the received frame with the redundant configuration No. for the management.
FIG. 15 shows a format example of a frame used in the present invention. The VLAN Tag in the frame is 4-byte VLAN information, and includes a VLAN ID, priority information, and the like. The VLAN ID is an identifier for identifying the VLAN, and assumes a unique value in a layer 2 network.
Operation Example: FIGS. 16-21
Firstly, a case of selecting a valid line within the main line/protection line on a reception side will be described in this embodiment in order to simplify the description. A case of selecting the valid line on a transmission side can be applied to the present invention without problems. Also, as an identifier assigned to the frame transmitted from the protection line port, “VLAN ID” is used in this embodiment. As one example of this “VLAN ID”, the redundant configuration No. is used. However, a case of setting the VLAN ID corresponding to the redundant configuration No. by a command input can be similarly applied.
FIG. 16 is an example of a network configuration in this embodiment (1). The transmission apparatus 100 _ 1 has reception ports R 1 -R 3 , and transmission ports S 1 -S 4 (main lines L 1 -L 3 and protection line L 4 ). The bandwidths of the transmission ports are, as shown in FIG. 16, S 1 (L 1 ): 100 Mbps, S 2 (L 2 ): 1 Gbps, S 3 (L 3 ): 1 Gbps, S 4 (L 4 ): 10 Gbps. Also, the transmission apparatus 100 _ 2 has reception ports R 1 -R 4 and transmission ports S 1 -S 3 . The bandwidths of the reception ports are, corresponding to the lines L 1 -L 4 , R 1 : 100 Mbps, R 2 : 1 Gbps, R 3 : 1 Gbps, and R 4 : 10 Gbps.
In this embodiment (1), a case where the redundant configuration is formed in the lines between the transmission apparatuses 100 _ 1 and 100 _ 2 and a frame is transmitted from the transmission apparatus 100 _ 1 to the transmission apparatus 100 _ 2 will now be described.
1) Firstly, an operation of the transmission apparatuses 100 _ 1 and 100 _ 2 up to forming the redundant configuration in the lines between the transmission apparatuses 100 _ 1 and 100 _ 2 shown in FIG. 16 will now be described referring to FIG. 8.
Firstly, in the redundant configuration setting operation of the transmission apparatus 100 _ 1 , the command accepting portion 6 accepts a command for forming the redundant configuration 1 with the transmission port S 1 being made the main line port W 1 and the transmission port S 4 being made the protection line port P 1 , and then notifies the settings to the redundant configuration manager 7 (at step T 10 in FIG. 10).
The redundant configuration manager 7 registers, as shown in the flowchart in FIG. 10, the settings in the redundant configuration management table TBL 1 (at step T 11 ), and executes the transmission port processing (at step T 12 ) and the reception port processing (at steps T 13 -T 15 ). Hereinafter, only the transmission port processing will be described in order to simplify the description, and the reception port processing will be described later in the operation of the transmission apparatus 100 _ 2 .
As shown in the flowchart in FIG. 10, as for the transmission port, the redundant configuration No. 1 , the main line port S 1 , the protection line port S 4 , and a VLAN ID 1 are notified to the redundant frame transmitter 4 (at step T 12 ).
Similarly, the command accepting portion 6 accepts a command for forming the redundant configuration 2 with the transmission port S 2 being made the main line port W 2 and the transmission port S 4 being made the protection line port S 2 , and the redundant configuration 3 with the transmission port S 3 being made the main line port W 3 and the transmission port S 4 being made the protection line port P 3 . The operation of this case is the same as the case of forming the redundant configuration 1 .
FIG. 13A shows the redundant configuration management table TBL 1 of the transmission apparatus 100 _ 1 upon thus forming the redundant configurations 1 - 3 .
It is to be noted that since the reception ports R 1 -R 3 of the transmission apparatus 100 _ 1 are ports which form no redundant configuration, the received frame processing management table TBL 2 of the reception ports R 1 -R 3 is initial setting unchanged as shown in FIG. 14A.
Hereinafter, the operation of the transmission apparatus 100 _ 2 will be described. The command accepting portion 6 accepts the command for forming the redundant configuration 1 with the reception port R 1 being made the main line port W 1 and the reception port R 4 as the protection line port P 1 , and then notifies the settings to the redundant configuration manager 7 . The redundant configuration manager 7 of the present invention registers, as shown in the flowchart in FIG. 10, the settings in the redundant configuration management table TBL 1 (at step T 11 ), and performs the transmission port processing (at step T 12 ) and the reception port processing (at steps T 13 -T 15 ). Since the transmission port processing has been described above, only the reception port processing will now be described.
The redundant configuration manager 7 notifies to the reception port selector 1 the redundant configuration No. 1 , the main line port R 1 , and the protection line port R 4 (at step T 13 ). Also, the redundant configuration manager 7 notifies to the ID deletion/transfer portion 8 _ 2 of the reception port R 1 which is the main line port “received frame=transfer” and the redundant configuration No. 1 (at step T 14 ), and notifies the ID deletion/transfer portion 8 _ 3 of the reception port R 4 which is the protection line port the received frame tag deletion, the VLAN ID 1 , and the redundant configuration No. 1 (at step T 15 ).
Similarly, the redundant configuration 2 is formed with the reception port R 2 as the main line port W 2 and the reception port R 4 as the protection line port P 2 and the redundant configuration 3 is formed with the reception port R 3 as the main line port W 3 and the reception port R 4 as the protection line port P 3 . The operation of this case is the same as the case of forming the redundant configuration 1 . FIG. 13B shows the redundant configuration management table TBL 1 of the transmission apparatus 100 _ 2 when the redundant configurations 1 - 3 are formed. Also, FIGS. 14B-14E show the received frame processing management tables TBL 2 of the reception ports R 1 -R 4 of the transmission apparatus 100 _ 2 .
FIG. 17 shows a state where the redundant configuration is thus formed in the lines L 1 -L 4 between the transmission apparatuses 100 _ 1 and 100 _ 2 .
2) Hereinafter, an operation up to transmitting the frame received at the reception ports R 1 -R 3 of the transmission apparatus 100 _ 1 from the main line port W 1 (transmission port SI) and the protection line port P 1 (transmission port S 4 ) of the redundant configuration 1 will be described as shown in FIG. 18.
The frames received at the reception ports R 1 -R 3 are transferred to the ID deletion/transfer portion 8 _ 2 . The ID deletion/transfer portion 8 _ 2 refers, as shown in the flowchart in FIG. 11, to the received frame processing management table TBL 2 shown in FIG. 14A (at step T 21 ). As a result, due to “received frame=transfer” and no redundant configuration No., the frames are transferred to the policing portion 2 (at steps T 22 -T 25 ).
Then, the frames are transferred from the policing portion 2 to the switching portion 3 . The switching portion 3 determines the transmission ports based on the destination MAC addresses of the frames. The operations of the policing portion 2 and the switching portion 3 are the same as those of the prior art.
When the transmission port determined by the switching portion 3 is the redundant configuration 1 , the frame is transferred to the redundant shaper portion 9 . The redundant shaper portion 9 of the redundant configuration 1 having received the frame performs shaping as shown in the flowchart in FIG. 12 (at steps T 30 and T 31 ), and transfers the frame to the redundant frame transmitter 4 of the redundant configuration 1 (at step T 32 ). It is to be noted that the operation up to setting the shaping rate in the redundant shaper portion 9 will described later in the embodiment (2).
The redundant frame transmitter 4 of the redundant configuration 1 to which the frame is transferred from the redundant shaper portion 9 copies the frame as shown in the flowchart in FIG. 9, and assigns the VLAN Tag of the VLAN ID 1 to the copied frame (at steps T 0 and T 1 ). The frame transferred from the redundant shaper portion 9 is transmitted from the main line port W 1 (transmission port SI), and the frame to which the VLAN Tag is assigned is transmitted from the protection line port P 1 (transmission port S 4 ) as shown in FIG. 18 (at step T 2 ), at which FIG. 15 shows a frame format transmitted from the protection line port P 1 (transmission port S 4 ).
Also, when the transmission ports determined by the switching portion 3 are the redundant configurations 2 and 3 , the frames to which the VLAN Tags are assigned are transmitted from the protection line ports P 2 and P 3 (transmission port S 4 ) as in the case of redundant configuration 1 , at which FIG. 19 shows a state where the frames are transmitted by all of the redundant configurations of the transmission apparatus 100 _ 1 .
As described above, the VLAN Tag is assigned to the frame, thereby enabling the frames of a plurality of redundant configurations to be transmitted with a single protection line.
3) Hereinafter, an operation up to transmitting the frames received at the main line port W 1 (reception port R 1 ) and the protection line port P 1 (reception port R 4 ) of the redundant configuration 1 of the transmission apparatus 100 _ 2 from the transmission ports S 1 -S 3 will be described as shown in FIG. 20.
The frame received at the main line port W 1 (reception port R 1 ) is transferred to the ID deletion/transfer portion 8 _ 2 of the main line port W 1 (reception port R 1 ). This ID deletion/transfer portion 8 _ 2 refers, as shown in a flowchart in FIG. 11, the received frame processing management table TBL 2 in FIGS. 14B-14E (at steps T 20 and T 21 ). Due to “received frame=transfer” and redundant configuration No. 1 (at steps T 22 -T 24 ), the reception port R 1 is notified to the reception port selector 1 corresponding to the redundant configuration 1 to transfer the frame (at step T 26 ).
The reception port selector 1 of the redundant configuration 1 to which the frame is transferred from the ID deletion/transfer portion 8 _ 2 determines that the reception port R 1 is a current valid port of the redundant configuration 1 without a fault occurrence since the reception port notified is “R1”, and transfers the frame to the policing portion 2 . Then, the frame is transferred from the policing portion 2 to the switching portion 3 , and the switching portion 3 determines the transmission port based on the destination MAC address of the frame, so that the frame is transferred to the redundant shaper portion 9 corresponding to the transmission port.
The redundant shaper portion 9 performs, as shown in FIG. 12, shaping at a shaping rate set (at steps T 30 and T 31 ), and transfers the frame to the redundant frame transmitter 4 (at step T 32 ). The redundant frame transmitter 4 transmits the frame from the main line port W 1 (transmission port S 1 ).
On the other hand, the frame received at the protection line port P 1 (reception port R 4 ) of the transmission apparatus 100 _ 2 is transferred to the ID deletion/transfer portion 8 _ 3 of the protection line port P 1 (reception port R 4 ). This ID deletion/transfer portion 8 _ 3 refers, as shown in a flowchart in FIG. 11, the received frame processing management table TBL 2 in FIG. 14E (at steps T 20 and T 21 ).
Due to the result of “the received frame Tag deletion” (at step T 22 ), the redundant configuration management table TBL 1 in FIG. 13B is retrieved based on the VLAN ID 1 of the VLAN Tag to acquire the redundant configuration No. 1 (at step T 27 ). Furthermore, the VLAN Tag is deleted from the frame (at step T 28 ), the reception port R 4 is notified to the reception port selector 1 corresponding to the redundant configuration No. 1 acquired, and the frame is transferred (at step T 29 ).
The reception port selector 1 of the redundant configuration 1 to which the frame is transferred from the ID deletion/transfer portion 8 _ 3 determines that the port R 4 is not a current valid port of the redundant configuration 1 since the notified port is R 4 , so that the frame is discarded.
Thus, even if the VLAN Tag is assigned to the frame received at the protection line port, the frame is normally discarded.
4) Hereinafter, operation up to transmitting the frame received at the protection line port P 1 (reception port R 4 ) from the transmission ports 1 - 3 when a fault has occurred at e.g. the main line port W 1 (reception port R 1 ) of the redundant configuration 1 of the transmission apparatus 100 _ 2 as shown in FIG. 21 will be described.
The reception port selector 1 of the redundant configuration 1 to which the frame having deleted therefrom the VLAN Tag is transferred from the ID deletion/transfer portion 8 _ 3 of the protection line port P 1 (reception port R 4 ) recognizes that the reception port R 1 during the fault occurrence is an invalid port. Accordingly, it is determined that the notified reception port R 4 is the current valid port of the redundant configuration 1 , so that the transferred frame is further transferred to the policing portion 2 .
Then, the frame is transferred from the policing portion 2 to the switching portion 3 , which determines the transmission port based on the destination MAC address of the frame, so that the frame is transferred to the redundant shaper portion 9 of the transmission port. The redundant shaper portion 9 performs, as shown in FIG. 12, shaping (at steps T 30 and T 31 ), and transmits the frame to the redundant frame transmitter 4 (at step T 32 ), so that the redundant frame transmitter 4 transmits the frame from the main line port W 1 (transmission port S 1 ).
Thus, even if the VLAN Tag is assigned to the frame received at the protection line port upon fault occurrence, it is normally determined that the frame is valid, so that the reception processing is performed.
Also in the cases of the protection line port P 2 of the redundant configuration 2 and the protection line port P 3 (reception port R 4 in both cases) of the redundant configuration 3 , the redundant configuration No. is acquired based on the VLAN ID of the VLAN Tag, and the frame from which the VLAN Tag is deleted is transferred to the reception port selector 1 of the redundant configuration, as in the case of the redundant configuration 1 .
As described above, the redundant configuration No. is acquired based on the VLAN ID of the VLAN Tag assigned to the frame, and the VLAN Tag is deleted, thereby enabling frames of a plurality of redundant configurations to be received with a single protection line.
Thus, a plurality of virtual 1:1 protections can be formed with a plurality of main lines and a single protection line.
FIG. 22 shows an arrangement of this embodiment (2) of the present invention. In FIG. 22, the same reference numerals as those in the embodiment (1) shown in FIG. 8 indicate the same portion. However, this embodiment (2) is different from the embodiment (1) in that a shaper value calculating portion 10 and a shaping rate management table TBL 3 are added.
The shaper value calculating portion 10 manages the shaping rates of all of the redundant configurations within the transmission apparatus 100 , and notifies the shaping rate to the redundant shaper portion 9 of each redundant configuration. FIGS. 23 and 24 respectively show the processing flow examples (1) (upon redundant configuration setting) and (2) (upon shaping rate change), which will be described later.
Also, the shaping rate management table TBL 3 is a table for managing shaping rate information of all of the redundant configurations within the transmission apparatus 100 . FIGS. 25A-25C show the embodiment of the table. This will be also described later.
FIG. 26 is an example of a network configuration applied to this embodiment (2). The transmission apparatus 100 _ 1 has reception ports R 1 -R 3 and transmission ports S 1 -S 12 . The bandwidths of the transmission ports are S 1 -S 10 : 1 Gbps, S 11 and S 12 : 10 Gbps. The transmission apparatus 100 _ 2 has reception ports R 1 -R 12 and transmission ports S 1 - 3 . The bandwidths of the reception ports are R 1 -R 10 : 1 Gbps, R 11 and R 12 : 10 Gbps. Also, the initial value of the shaping rate forming the redundant configuration is the bandwidth of the main line port.
1) Firstly, an operation of the transmission apparatus 100 _ 2 up to forming redundant configurations 1 - 10 in the transmission line L between the transmission apparatuses 100 _ 1 and 100 _ 2 shown in FIG. 27 will be described.
Firstly, the operation of forming the redundant configuration 1 will be described. The command accepting portion 6 having received a command of forming the redundant configuration 1 with the transmission port S 1 being made the main line port W 1 and the transmission port S 11 being made the protection line port P 1 notifies, as shown in the processing flow example (1) (upon redundant configuration setting) of FIG. 23, the redundant configuration No. 1 , the protection line transmission port S 11 , and a shaping rate X=1 Gbps to the shaper value calculating portion 10 (at step T 40 ). The shaper value calculating portion 10 to which the settings have been notified retrieves the shaping rate management table TBL 3 at the protection line transmission port S 11 . However, since there is not yet another redundant configuration using the same protection line port (at step T 41 : Y=0), the shaping rates X+Y=1 Gbps of the redundant configuration 1 are compared with the bandwidth Z of the protection line port S 11 =10 Gbps (at step T 42 ).
In order to provide a QoS guarantee in the protection line transmission port S 11 equivalent to the main line port W 1 at this moment, it is required to consider the VLAN Tag as an identifier assigned when the frame is transmitted from the protection line transmission port S 11 . As shown in the frame format in FIG. 15, the minimum values of the frame sizes before and after assigning the VLAN Tag are respectively 64 bytes and 68 bytes, so that the increase rate of the frame sizes is 6.25% (68/64=1.0625).
Namely, in order to transmit a frame to which the VLAN Tag is assigned from the protection line transmission port S 11 while a frame of 1 Gbps is transmitted from the main line port W 1 , the bandwidth of 1 Gbps*1.0625=1.0625 Gbps is required. Accordingly, when the shaping rate is compared with the bandwidth of the protection line port, it is required to compare the value of shaping rate*1.0625 with the bandwidth of the protection line port (at step T 43 ).
Accordingly, the comparison between the shaping rate and the bandwidth of the protection line port assumes 1 Gbps*1.0625=1.0625 Gbps<10 Gbps is acquired, which can guarantee the QoS. Therefore, the redundant configuration No. 1 , the protection line port P 1 (S 11 ), and the shaping rate X=1 Gbps are registered in the shaping rate management table TBL 3 (at step T 44 ). The shaping rate X=1 Gbps is notified to the redundant shaper portion 9 corresponding to the redundant configuration 1 (at step T 45 ), at which FIG. 25A shows the shaping rate managing table TBL 3 .
Hereinafter, the operation of forming the redundant configuration 2 will be described. The command accepting portion 6 having received the command for forming the redundant configuration 2 with the transmission port S 2 as the main line port W 2 and the transmission port S 11 as the protection line port P 2 notifies the redundant configuration No. 2 , the protection line port P 2 (transmission port S 11 ), and the shaping rate X=1 Gbps to the shaper value calculating portion 10 . The shaper value calculating portion 10 to which the settings have been notified retrieves the shaping rate management table TBL 3 at the protection line transmission port S 11 (at steps T 40 and T 41 ) as shown in the flowchart in FIG. 23, and compares the total value X+Y of a shaping rate Y=1 Gbps of the redundant configuration 1 mentioned above and the shaping rate X=1 Gbps of the redundant configuration 2 using the same protection line transmission port S 11 with a bandwidth Z of the protection line transmission port S 11 =10 Gbps (at steps T 42 and T 43 ). It results in that “(1 Gbps+1 Gbps)*1.0625=2.125 Gbps”<“10 Gbps⇄, which can guarantee the QoS. Therefore, as shown in FIG. 25B, the redundant configuration No. 2 , the protection line transmission port S 11 , and the shaping rate X=1 Gbps are registered in the shaping rate management table TBL 3 (at step T 44 ). The shaping rate X is notified to the redundant shaper portion 9 of the redundant configuration 2 (at step T 45 ).
The operations of forming the redundant configurations 3 - 9 are performed as in the case of the redundant configuration 2 (see FIG. 25B).
Hereinafter, the operation of the transmission apparatus 100 _ 1 in the case of adding the redundant configuration 10 will be described. The command accepting portion 6 having received the command for forming the redundant configuration 10 with the transmission port S 10 as the main line port W 10 and the transmission port S 11 as the protection line port P 10 notifies the redundant configuration No. 10 , the protection line port P 10 (transmission port S 11 ), and the shaping rate X=1 Gbps to the shaper value calculating portion 10 as shown in FIG. 23 (at step T 40 ).
The shaper value calculating portion 10 to which the settings have been notified retrieves the shaping rate management table TBL 3 at the protection line transmission port S 11 , and compares the total value X+Y of the sum Y of shaping rates=9 Gbps of the redundant configurations 1 - 9 and the shaping rate X=1 Gbps of the redundant configuration 10 using the same protection line port with the bandwidth Z of the protection line transmission port S 11 =10 Gbps (at steps T 41 -T 43 ).
It results in that “(9 Gbps+1 Gbps)*1.0625=10.625 Gbps”>“10 Gbps”, so that a setting error is notified to the command accepting portion 6 (at step T 46 ).
Thus, when the transmission port S 11 is made the protection line port, the redundant configuration can not be formed. Therefore, the transmission port is changed to the port S 12 to form the redundant configuration 10 . This operation is the same as the case of the redundant configuration 1 except the protection line port, at which FIG. 25B shows the shaping rate management table.
Thus, when the total value of the shaping rates of the redundant configurations which set the same transmission port to the protection line port exceeds the bandwidth of a certain protection line port, it is possible to prevent the redundant configuration setting from being made.
2) Hereinafter, an operation of the transmission apparatus 100 _ 1 in the case of changing the shaping rate of the redundant configuration 1 will be described.
The command accepting portion 6 having accepted a command for changing a shaping rate X′ of the redundant configuration 1 to 500 Mbps notifies, as shown in the flowchart in FIG. 24, the redundant configuration No. 1 and the shaping rate X′=500 Mbps to the shaper value calculating portion 10 (at step T 50 ). The shaper value calculating portion 10 to which the settings are notified retrieves the shaping rate management table TBL 3 at the redundant configuration No. 1 to acquire the protection line port S 11 (at step T 51 ). The shaper value calculating portion 10 retrieves the shaping rate management table TBL 3 at the protection line transmission port S 11 , and compares the total value X′+Y of the sum Y of the shaping rates except the redundant configuration 1 , 8 Gbps and the shaping rate X′ after the change of the redundant configuration 1 , 500 Mbps with the protection line port S 11 bandwidth Z=10 Gbps (at steps T 52 -T 54 ).
It results in that “(8 Gbps+500 Mbps)* 1.0625=9.03125 Gbps”<“10 Gbps”, so that the shaping rate management table TBL 3 is retrieved based on the redundant configuration No. 1 , and the shaping rate X′ is updated to 500 Mbps (at step T 55 ). Also, the shaping rate X′ is notified to the redundant shaper portion 9 of the redundant configuration 1 (at step T 56 ). FIG. 25C shows the shaping rate management table at this time. In the case of “(8 Gbps+500 Mbps)* 1.0625=9.03125 Gbps”>“10 Gbps” at step T 54 , an error notification is performed to the command accepting portion 6 (at step T 57 ).
As mentioned above, when the total value of the shaping rates of the redundant configurations where the same transmission port is set as the protection line port even after the redundant configuration having been formed does not exceed the bandwidth of the protection line port, the shaping rate can be changed.
Thus, it becomes possible to accept the redundant configuration setting and the shaping rate setting so that the total value of the shaping rates of the redundant configurations where the same transmission port is set as the protection line port does not exceed the bandwidth of the protection line port. Also, even when the frame to which the VLAN Tag is assigned is transmitted from the protection line, the QoS guarantee equivalent to that of the main line where the VLAN Tag is not assigned to the frame can be provided.
It is to be noted that the present invention is not limited by the above-mentioned embodiments, and it is obvious that various modifications may be made by one skilled in the art based on the recitation of the claims.