JPH08307426A - Atm device - Google Patents

Abstract

PURPOSE: To provide an ATM communication system of high reliability. CONSTITUTION: The real ports 11 to 13 of an ATM circuit are collectively set opposite to a logical port 23 which performs the transmission/reception operations based on a map table. Then the the transmission/reception operations are carried out through the ports 11 to 13. At the same time, the substitute ports are set opposite to the ports 11 to 13 based on a substitute table. When a real port of the ATM circuit has a fault, its substitute port substituting the port is used for execution of the transmission/reception operations. In such a constitution, the reliability of an ATM device is improved and the available band of the ATM device is increased.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an ATM (Asynchr)
and a line management function thereof.

[0002]

2. Description of the Related Art A conventional multi-ATM line communication system is disclosed in Japanese Patent Laid-Open No. 5-191434. This conventional communication system will be described with reference to FIG.

In FIG. 1, the conventional communication system is A
An ATM communication system that performs communication via a TM communication path,
The transmitter 94 adds a multilink control header to the ATM cell, and the receiver 96 analyzes the header to realize control of a plurality of ATM lines.

That is, the transmitter 94 and the receiver 96 are
When performing ATM communication via the TM communication path 2,
ATM multilink group identification information 901 and ATM multilink sequence identification information 902 are inserted in the header 90 of the ATM cell 91, and these identification information 901 are inserted.
And 902 perform ATM cell reception processing. As a result, even if a failure occurs in any of the lines, the communication can be continued using the other lines in the group, and the reliability can be improved.

[0005]

SUMMARY OF THE INVENTION The conventional ATM described above.
The communication system is premised on adding a special header to the beginning of an ATM cell. Therefore, the cell length is 5
An ATM device that complies with the criterion of 3 bytes has a drawback in that this conventional technique cannot be practically applied.

The present invention has been made to solve the above-mentioned drawbacks of the prior art, and its purpose is to realize an ATM communication system with high reliability.
It is to provide an M device.

[0007]

An ATM device according to the present invention is an ATM device having an input / output port for transmitting and receiving, and a map table that associates a plurality of ATM line ports with the input / output port. It is characterized in that it includes a transmitting / receiving means for transmitting / receiving using the plurality of associated ATM line ports.

Another ATM device according to the present invention uses an alternative table that associates an ATM line port with an alternative port that replaces the port, and the alternative table instead of the port when a failure occurs in the ATM line port. And a transmission / reception unit that performs transmission / reception using an alternative port corresponding to the port shown.

[0009]

The map table associates a plurality of ATM line ports with input / output ports for transmitting and receiving. Transmission and reception are performed using the plurality of ATM line ports associated with each other. In addition, by the substitution table, AT
The M line port is associated with an alternative port that replaces the port. When a failure occurs in the ATM line port, transmission / reception is performed using the alternative port indicated by the alternative table instead of that port.

[0010]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of an ATM device according to the present invention. In the figure, the ATM device 1 comprises a port management unit 2 and a communication processing unit 3.

The port management unit 2 is an ATM Adaptation Layer in the ATM protocol layer.
An AAL processing unit 21 that performs (AAL) processing, and an ATM virtual path identifier (VPI; Virt) on an ATM real port.
and a virtual channel identifier (VCI; Virtual Channel I)
a VCMAPPING processing unit 22 for associating the VPI and VCI on the logical port of the port management unit. Also, the port management unit 2
Logical ports 23, 24, 25, 26, and 27, which are logical input / output ports viewed from the communication processing unit 3, are provided.

The communication processing unit 3 is a signaling processing unit 3 which performs protocol processing relating to connection and disconnection of ATM paths.
1, a bandwidth management unit 32 that manages traffic on the ATM communication path, a VC resource management unit 33 that allocates the use of the ATM path, and a communication application processing unit 34 that performs various communication services on the ATM communication path. It is configured to include and.

Next, the operation of this embodiment will be described with reference to FIGS.

The ATM device 1 has real ports 11, 12, 1
It is connected to the ATM real line via 3, 14, and 15.

The ATM actual line is further divided into a logical communication path called an ATM communication protocol path, and data flowing on the line is processed in units of this path. This is ATM
This is realized by dividing the data flowing on the actual line into units called 53-byte cells, and adding the path identification numbers VPI and VCI to the header of this cell. The format of this cell is shown in FIG.

GFC in the figure is a generic flow control,
PT is the payload type, CLP is the cell loss priority, H
EC is header error control. These are all ATM layer control headers, and are the items specified by the recommendation. The VPI and VCI are unique within the real port.

Returning to FIG. 1, the port management unit 2 uses, for example, A
When a cell is received from each port of TM real line, AAL
In the processing unit 21, after the protocol processing of the AAL layer of the ATM protocol is performed, the processing is performed by VCMAPPING.
It is passed to the processing unit 22.

The VCMAPPING processing unit 22 is shown in FIG.
It has a VC map table as shown in (a).

As shown in the figure, the VPI of the real port 11, the VPI of the 11th, the VCI of the logical port, and the VPI of the logical port
11th VCI and 12th are matched. Therefore, the VCMAPPING processing unit 22 regards the received data of the VPI 11 VCI 14 of the real port 11 as the VPI 11 VCI 12 of the logical port 23, and the communication processing unit 3
Notify to

In addition, the real port 11 VPI 12 VC
VPI11 VCI13 of I15 and logical port 23
The numbers are associated with each other. Therefore, VCMAPP
The ING processing unit 22 uses the VPI 12 V of the real port 11
Received data of CI15 is VPI1 of logical port 23
The communication processing unit 3 is notified as No. 1 VCI No. 13. Hereinafter, they are similarly associated.

When transmitting data, the opposite correspondence is made. That is, the logical port is associated with the real port.

Further, referring to the figure, there is an alternative number in the portion corresponding to the real port in the VC map table, and this number is associated with the number in the alternative real port table. (B) and (c) of the same figure are alternative real port tables.

In this example, it is assumed that the alternative real port table in FIG. 7B corresponds to the alternative number 1 and the alternative real port table in FIG. 7C corresponds to the alternative number 2. That is,
As shown in (b) of the figure, the V of the real port 11
Alternate ports for PI11 VCI14 are VPI11 VCI15 and real port 1 of real port 12
The third VPI is the 11th VCI and the 15th. Further, as shown in FIG. 7C, the VPI of the real port 12
The alternative ports for the 11th VCI 14th are the VPI 11th VCI 15th of the real port 11th and the VPI 11th VCI 16th of the actual port 13th.

In short, when a failure occurs in the ATM line, if the real port of the ATM line has an alternative port,
Communication can be continued using the alternate port instead of the faulty port. Hereinafter, this alternative process will be described.

When the VCMAPPING processing unit 22 detects a failure on the ATM line real port number 11, if there is an alternative number in the VC map table of FIG. 7A, the alternative real port table corresponding to that number. One real port number and one VPI and VCI are extracted. Then, in the VC map table, the actual port number, VPI, and VCI having this alternative number are replaced with the values in the alternative table.

As a result, the port number and VPI, VCI of the alternate real port table using the VPI and VCI of the logical port corresponding to the failure are deleted from the alternate real port table.

Incidentally, the alternate number 0 on the VC map table of FIG. 9A indicates that there is no real port to be substituted at the time of failure.

Further, the alternative process will be described with reference to FIG. When a line failure occurs, it is first determined whether an alternative number is set in the VC map table (step 81). If the alternative number is not set, the process ends (step 81 → 85).

When the alternative number is set, it is then judged whether or not the port number is set in the alternative real port table (step 82). If the port number is not set, the process ends (step 82 → 8).
5).

When the port number is set, the port number, VPI, and VCI in the alternative real port table are set to V.
It is set in the C map table (step 83). next,
The port number used in the alternative real port table is deleted (step 84). In this case, the port number is set to 0 (zero) so that the port number is in use and is not used for another substitution.

With the above, the processing is completed (steps 84 → 85). When the failure is recovered, the communication may be continued in the state after the substitution, or the communication may be continued after returning to the state before the substitution.

As described above, the ATM according to the present invention
The device groups the ATM real line ports into logical ports by the VC map table without adding a new header to the 53-byte cells, and has an alternate port table to allow communication via the logical port. Since the communication can be continued even if a failure occurs on the real line to the communication processing unit that operates, it is possible to perform communication with higher reliability than the hardware and software that configure the ATM communication path. .

Further, since a plurality of real lines are grouped as one logical port, the bandwidth of the logical port becomes the total of the bandwidths of the real lines included therein, and the apparent bandwidth that can be managed via the logical port is set. It can be expanded. As a result, the amount of data transferred per unit time increases and the transmission efficiency improves.

The extension of the bandwidth will be described with reference to FIGS.

Generally, there are ATM lines of 6, 25, 50, 150 and 600 [Mbps] depending on the bandwidth. As described above, by converting the real port into the logical port by the port management unit 2, the communication processing unit 3 can perform processing without depending on the bandwidth of the real port (line).

For example, as shown in FIG.
The actual port of 0 [Mbps] is unchanged at 150 [Mbps
Consider the ATM device used as the logical port of [s].

In such a device, even if the connection destinations are dispersed and the real ports have three configurations of 50 [Mbps] as shown in FIG. 6, the three real ports are distributed. The VC map table in the port management unit 2 can be converted into one logical port. That is, a plurality of A
This is to associate a plurality of TM line ports with a logical port. By associating the plurality of real ports with one logical port, the influence of the real port distribution on the communication processing unit 3 can be avoided.

Further, as shown in FIG. 7, in the port management unit 2, 50 [Mbps], 150 [Mbp]
s] and 600 [Mbps] are associated with one logical port, the logical port is 800 [Mb
ps]. Therefore, the communication processing unit 3 sets 600
Bandwidths above [Mbps] can also be used.

If there is an alternative port as shown by the dotted line in FIG. 8, as described above, the port management unit 2 can perform a service to switch to the alternative port, a detour at the time of failure, etc. You can do it.

Referring back to FIG. 1, one real port 15 is associated with three logical ports 25, 26 and 27 in FIG. As described above, by associating a plurality of logical ports with one real port and changing a plurality of lines originally used to one, various software in the communication processing unit 3 can be changed. Instead, communication can continue. With this, for example, in the case of integrating multiple branches,
Even if the lines for each branch are combined into one, there is no need to change the software.

The present invention can further have the following aspects in relation to the claims.

(1) An ATM device having a plurality of input / output ports for transmission / reception, wherein a map table for collectively associating a plurality of the input / output ports with the ATM line ports and the associated ATM line ports are provided. ATM including transmitting / receiving means for transmitting / receiving using
apparatus.

[0044]

As described above, the present invention does not add a new header to an ATM cell, but a plurality of ATM cells.
By treating the real ports of the line as one logical port and preparing an alternative port, it is possible to improve reliability and use a large band.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an ATM device according to an embodiment of the present invention.

FIG. 2A is a diagram showing a configuration example of a VC map table, and FIGS. 2B and 2C are diagrams showing a configuration example of an alternative real port table.

FIG. 3 is a diagram showing a format of an ATM cell.

FIG. 4 is a flowchart showing an alternative processing operation.

FIG. 5: A real port of 150 [Mbps] is set to 150 [Mb
2 is a schematic configuration diagram of an ATM device used as a logical port of [ps].

FIG. 6 is a diagram showing the configuration of FIG.
It is a schematic block diagram of an ATM device when it is dispersed in [Mbps].

FIG. 7: 50 [Mbps], 150 [Mbps], 60
It is a schematic block diagram of an ATM device in the case of associating three real ports of 0 [Mbps] with one logical port.

FIG. 8 is a schematic configuration diagram of an ATM device when there is an alternative port.

FIG. 9 is a block diagram showing a configuration of a conventional ATM device.

[Explanation of symbols]

 1 ATM device 2 Port management unit 3 Communication processing unit 11, 12, 13, 14, 15 Real port 21 AAL processing unit 22 VCMAPPING processing unit 23, 24, 25, 26, 27 Logical port 31 Signaling processing unit 32 Bandwidth management unit 33 VC resource management unit 34 Communication application processing unit

Claims (3)

[Claims] 1. An ATM device having an input / output port for transmission / reception, comprising: a map table that associates a plurality of ATM line ports with the input / output ports; and a plurality of associated ATM line ports. An ATM device comprising a transmitting / receiving means for transmitting and receiving using the ATM device. 2. A substitution table that associates an ATM line port with a substitution port that substitutes the port, and the AT.
An ATM device, comprising: a transmission / reception unit that performs transmission / reception using an alternative port corresponding to the port indicated by the alternative table instead of the port when a failure occurs in the M line port. 3. The transmitting / receiving means determines whether or not an alternative port corresponding to the ATM line port exists in the alternative table when a failure occurs in the ATM line port, and the determining means determines that the alternative port exists. When the ATM port is replaced with the alternative port indicated by the alternative table,
An ATM device according to claim 2, further comprising means for setting as a line port.