JPH07143134A - Transmission station - Google Patents

Abstract

PURPOSE:To improve the extension performance of a user program and entity by providing an address registration means to which an individual MAC(Medium Access Control) address is registered and an individual entity to the station. CONSTITUTION:This transmission station 21 is provided with a MAC 23, a specific entity set 24A, a user program 25A, an individual entity set 24B, and a user program 25B. That is, an individual MAC address 26B different from a specific MAC address 26A is registered, the individual entity set 24B corresponding to the individual MAC address 26B is provided. When the extension of a transmission station is desired, the individual MAC address is registered and the individual entity set 24 B is used. Thus, the extension performance of the user program is improved by registering plural MAC address.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission station connected to a LAN, and more particularly to a transmission station capable of improving the expandability of user programs and entities by registering a plurality of MAC addresses.

[0002]

2. Description of the Related Art In a LAN, the International Standards Organization (ISO)
A transmission station is used that is divisible into seven layers based on the seven-layer model of the open system interconnection (OSI) in.

FIG. 4 is a block diagram showing the structure of a transmission station of this type. This transmission station is an OS
Physical layer 1, which is the first layer (bottom layer) in the I model,
The second layer is the data link layer 2, the third layer is the network layer 3, the fourth layer is the transport layer 4, the fifth layer is the session layer 5, the sixth layer is the presentation layer 6, and the seventh layer. It has an application layer 7 which is the (top layer).

Each of these layers is a LAN protocol,
For example, in MAP (Manufacturing Automation Protocol), the physical layer 1 to the data link layer 2 are MAC (Me
diumAccess Control) 1a to LLC (Logical Link
Control) 2a, application layer 7 is MM
It corresponds to S (Manufacturing Message Specification) 7a. The intermediate layer interposed between the LLC 2a and the MMS 7a is omitted. Further, the application layer 7 having the same function and protocol can use only a unique entity in a lower layer such as the presentation layer 6 or the like.

Such transmission stations are in LA
As shown in FIG. 5, a 6-byte MAC address assigned to the MAC is used as the identification number of each station 8 and 9 connected via N.

For example, when one transmission station 9 sends a message to another transmission station 8, as shown in FIG. 6, Preamble, SD, FC, DA, SA, Data, FCS,
DA (Destination Address) that specifies the destination transmission station address in 6 bytes in the message consisting of ED
SA in which the MAC address of another transmission station 8 is set in s) and the source station address is 6 bytes.
Set the MAC address of the own station in (Source Address).

Preamble is a bit pattern for bit synchronization, and SD (StartDelimiter) is byte data indicating the start of a frame. In addition, FC (Fram
e Control) is byte data indicating the type of frame, and Data is information indicated by a plurality of bytes. FCS (Fr
The ame check sequence) is 4-byte data for checking the normality of the frame, and the ED (End Delimiter) is byte data indicating the end of the frame. Also, the MAC address assigned to the transmission station has a group address, but this group address is assigned to a plurality of transmission stations, and SA (hereinafter,
Source address. ) Is not set.

Therefore, as shown in FIG. 7, such a transmission station 9 has a user program 1 stored in advance.
0A is executed to create a message containing the execution result, and this message is sent from the MAC to the application layer (7th layer).
It is possible to transmit to another transmission station 8 based on the unique entity set 11 up to.

It should be noted that the user program 10A is expandable, and the user program 10B corresponding to the expanded portion is added to the transmission station 9 before the addition, and as shown in FIG. The program 10B is ported to a new transmission station.

At this time, the data transmitted to the user program 10B is transmitted to the transmission station 9 before the expansion and is transmitted to the new transmission station 11 after the expansion. In addition, the user programs 10A and 10B are changed due to the change of the transmission destination. When deleting the transmission station 12, the transmission station 1 to be deleted
The user program 10B stored in No. 2 is ported to the existing transmission station 9, and accordingly, the user programs 10A and 10B are changed.

[0011]

However, in the above-mentioned transmission station, if the number of transmission stations is increased or decreased, the user program 10 will be used if the system is large.
There is a problem that the labor of changing A and 10B and checking the changed contents becomes enormous.

It should be noted that such an increase or decrease in the number of transmission stations is a normal work, and for example, when the LAN system is started up, the load on the transmission line and the user program is low, so a small-scale transmission is performed for cost reduction. When a station is installed and the load of a transmission line or a user program increases in the future, a new transmission station is added.

Further, as shown in FIG. 9, when the set from LLC to the application layer is the entity set 13, the number of channels is limited because the entity set 13 is unique. However, you may want to use your application beyond this limit. At this time, in the same type of application layer, as shown in FIG. 10, normally only one entity is allowed from the lower layer, and it is impossible to increase the functional unit such as newly activating a task or process. There is a problem that it is difficult to exceed the limit of.

The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a transmission station capable of improving the expandability of a user program or entity by registering a plurality of MAC addresses.

[0015]

According to a first aspect of the invention, in a transmission station connected to a LAN and having a unique entity and a unique MAC address designating this unique entity, an individual MAC different from the unique MAC address is provided. The transmission station includes an address registration unit in which an address is registered and an individual entity corresponding to the individual MAC address registered in the address registration unit.

The invention according to claim 2 is the invention according to claim 1, wherein when the message from the individual entity is transmitted to another station, the individual MAC registered in the address registration means. It is a transmission station to which a message creating means for creating the message by adding the address to the source address in the message is added.

[0017]

Therefore, according to the invention corresponding to claim 1, by taking the above-mentioned means, the address registering means in which the individual MAC address different from the unique MAC address is registered and the address registering means are registered in the address registering means. If an individual entity corresponding to an individual MAC address is provided and it is desired to increase the number of transmission stations or the number of entities, the individual MAC address can be registered and the individual entity can be used. The extensibility of programs and entities can be improved.

Further, in the invention according to claim 2, when the message from the individual entity is transmitted to another station, the message creating means uses the individual MAC address registered in the address registering means as the source in the message. Since it will be set to the address and a message will be created,
In addition to the operation of claim 1, it can function as a transceiver station.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a transmission station and its peripheral configuration according to a first embodiment of the present invention.
The transmission station 21 includes a MAC 23 connected to the LAN 22 and an LL corresponding to an upper layer of the MAC 23.
A unique entity set 24A including layers from C to the application layer, a user program 25A that can use this unique entity set 24A, and M
An individual entity set 24B composed of each layer from the LLC corresponding to the upper layer of the AC 23 to the application layer
And a user program 25B capable of using the individual entity set 24B.

The unique entity set 24A is designated by the unique MAC address 26A registered in the transmission station 21. Further, the individual entity set 24B is designated by the individual MAC address 26B registered in the transmission station 21.

Further, when the transmission station 21 sends a message from the individual entity set 25B to another transmission station 27, the individual MAC address 26 for designating the individual entity set 25B.
It has the function of creating a message by setting B to the source address in the message.

The other transmission station 27 is a LAN.
Connected to the transmission station 21 via 22 and LAN
22 connected to the MAC 28, an entity set 29 connected to the MAC 28 and each layer from the LLC to the application layer, another MAC address 30 designating this entity set 29, and a user who can use the entity set 29 And a program 31.

Next, the operation of the transmission station configured as described above will be described. Now, the transmission station 21
Is a unique MAC address 26A and an individual MAC address 2
6B is registered.

Here, the other transmission station 27 sets the other MAC address 30 as the source address of the message and sets the individual MAC address 26A as DA (destination address) and sends this message to the LAN 22.

That is, the user program 31 of the other transmission station 27 treats the user program 25B existing in the transmission station 21 as a user program existing in a station different from the transmission station 21 and transmits the message. To do.

The MAC 23 of the transmission station 21 is LA
The message is received via N22 and the information in the message is sent to the individual entity set 24B based on the individual MAC address 26B in the message. The individual entity set 24B sends the information in the message to the user program 25B.

This completes the reception process of the message transmitted from the other transmission station 27. Next, a message transmission process in the transmission station 21 will be described.

In the transmission station 21, according to the user program 25B, the information to be transmitted is given to the individual entity 24B. The individual entity set 24B creates a message based on this information and provides the message to the MAC 23. The MAC 23 completes the message by setting the individual MAC address 26B as the source address of this message, and the completed message is LA
Send to N22.

The other transmission station 27 is the LAN 22.
Receive this message via. As described above, according to the first embodiment, the individual MAC address 26B different from the unique MAC address 26A is registered, and the individual entity set 24B corresponding to the individual MAC address 26B is provided. Even if you want to increase the number of stations, individual MAC address 26
Since it is only necessary to register B and use the individual entity set 24B, it is possible to improve the expandability of the user program by registering a plurality of MAC addresses.

Further, according to the first embodiment, when the message from the individual entity set 24B is transmitted to the other transmission station 27, the individual MAC address 26B is set as the source address in the message and the message is transmitted. Since it is created, it can function as a transceiver station.

Further, according to the first embodiment, when connecting a plurality of LANs having a station configuration in which the middle layer is omitted, and when a message is to be transmitted to a plurality of stations, there is no middle layer, so the message is Unlike the conventional method in which the destination station identification number cannot be set in the transmission station 21, the transmission station 21 has a function of a plurality of stations. Therefore, by transmitting a message to the transmission station 21, the message is transmitted to a plurality of stations. The same effect as what was done can be obtained.

According to the first embodiment, when it is desired to transmit a message to a station on another network,
By setting the individual MAC address 26B of the own station as the source address in the message and setting the MAC address of the destination station in DA, the message can be transmitted to stations in other networks.

Furthermore, creating a new entity set 24B in the first embodiment is equivalent to activating a new task, so that it can be easily executed.

Similarly, a new individual MAC address 26B is newly added.
The addition of is equivalent to the conventional registration of a group address, and thus can be easily performed. Also, when sending a message, the source address is
Although setting as the C address 26B involves changing the actual feeling of the MAC, it can be carried out sufficiently easily as compared with the conventional case where the user program was changed.

Next, a transmission station according to the second embodiment of the present invention will be described. FIG. 2 is a block diagram showing this transmission station and its peripheral configuration. The same parts as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted, and only different parts will be described here.

That is, the apparatus of this embodiment removes the limitation of the entity of each layer. Specifically, as compared with the apparatus shown in FIG. 1, the user program 25B is omitted and the user program 25A has both entity sets. 24
A and 24B can be used.

The unique entity set 24A is designated as the unique MAC address 26A, and the individual entity set 24B is designated as the individual MAC address 26B.

Here, the number of channels and the like are limited in the unique entity set 24A. However, in the transmission station 21, since the individual entity set 24B is provided in parallel with the unique entity set 24A, it is possible to remove the restriction of the unique entity set 24A and use the application.

As described above, according to the second embodiment, different MAs are provided to the entity sets 24A and 24B.
By adding the C addresses 26A and 26B, one transmission station 21 can be apparently provided with two station functions, so that the application can be used beyond the limitation of the unique entity set 24A.

In addition, creation of a plurality of entity sets,
The addition of the new individual MAC address and the change of the source address can be easily performed as described above.
The program of each layer controls the flow of information by the value of SAP (Service Access Point).
This SAP has a limitation that only a finite value can be assigned to each entity set. However, according to the second embodiment, a plurality of MAs may be provided in one transmission station 21.
1 by assigning C addresses 26A and 26B
Since a plurality of entity sets 24A and 24B exist in one transmission station 21, it is possible to provide a desired number of SAPs having a finite value and remove the limitation of the SAP in one transmission station 21. It is possible to have a plurality of station functions in one transmission station.

Next, a transmission station according to the third embodiment of the present invention will be described. FIG. 3 is a block diagram showing this transmission station and its peripheral configuration. The same parts as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted, and only different parts will be described here.

That is, the apparatus of this embodiment is a user program expanded from that of the apparatus of the first embodiment. Specifically, as shown by the solid line, as compared with the apparatus shown in FIG.
m entity sets 24A, 24B, ..., 24n
And each entity set 24A, 24B, ..., 24n
User programs 25A and 25 that can be used individually
, 25n. .., 24n corresponding to each entity set 24A, 24B, ..., 24n is registered in the transmission station 21.

Here, as described above, each user program 25A, 25B, ..., 25n uses the corresponding entity set 24A, 24B ,.
Transmission and reception with another transmission station 27 can be performed through C23.

The entity sets 24A, 24
.., 24n, the user programs 25B, ..., 25n other than the user program 25A are omitted, and each entity set 24 is expanded from the user program 25A as shown by a broken line.
, 24n can be used.
Also, each entity set 24A, 24B, ..., 24
n is a corresponding MAC address 26A, 26B,
.., 26n are registered in the transmission station.

In this way, the entity sets 24A, 2
4B, ..., 24n, user program 2
5A is each entity set 24A, 24B, ..., 24
By using n at the same time, the restriction on the entity set can be removed.

As described above, according to the third embodiment, m
, 25n and entity sets 24A, 24B corresponding to the user programs 25A, 25B, ...
, 24n are provided, and each entity set 24A, 24
MAC address 26 for individually specifying B, ..., 24n
By registering A, 26B, ..., 26n, in addition to the effect of the first embodiment, the expandability of the user program can be further improved.

According to the third embodiment, one user program 25A is used for each entity set 24A, 2.
4B, ..., 24n can be used, the expandability of the entity set can be further improved in addition to the effect of the second embodiment. In addition, the present invention can be modified in various ways without departing from the scope of the invention.

[0048]

As described above, according to the invention corresponding to claim 1, the individual MA different from the unique MAC address is used.
When the address registration means in which the C address is registered and the individual entity corresponding to the individual MAC address registered in the address registration means are provided, and it is desired to increase the number of transmission stations or the number of entities, the individual MAC address is registered to individually Since the entity may be used, it is possible to provide a transmission station capable of improving the expandability of the user program and the entity by registering a plurality of MAC addresses.

According to the invention corresponding to claim 2,
2. When transmitting a message from an individual entity to another station, the message creating means creates the message by setting the individual MAC address registered in the address registering means to the source address in the message. In addition to the above effect, it is possible to provide a transmission station that can function as a transceiver station.

[Brief description of drawings]

FIG. 1 is a block diagram showing a transmission station and its peripheral configuration according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a transmission station and its peripheral structure according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a transmission station and its peripheral structure according to a third embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional transmission station.

FIG. 5 is a diagram for explaining conventional allocation of MAC addresses.

FIG. 6 is a diagram for explaining the structure of a conventional message.

FIG. 7 is a block diagram for explaining the configuration of a conventional transmission station before expansion.

FIG. 8 is a block diagram for explaining the configuration of a conventional transmission station after expansion.

FIG. 9 is a block diagram illustrating a conventional entity set.

FIG. 10 is a block diagram illustrating a limitation of a conventional entity.

[Explanation of symbols]

21 ... Transmission station, 22 ... LAN, 23, 28 ...
MAC, 24A ... Unique entity set, 24B ... Individual entity set, 25A, 25B, 31 ... User program, 26A ... Unique MAC address, 26B ... Individual MAC address, 27 ... Other transmission station, 29
... entity set, 30 ... other MAC address.

Claims (2)

[Claims] 1. A transmission station that is connected to a LAN and has a unique entity and a unique MAC address that designates this unique entity, and an address registration unit in which an individual MAC address different from the unique MAC address is registered, and this address registration. And a separate entity corresponding to the separate MAC address registered in the means. 2. The transmission station according to claim 1, wherein when the message from the individual entity is transmitted to another station, the individual MAC address registered in the address registration means is used as a source address in the message. A transmission station, wherein a message creating means for setting and creating the message is added.