JPH06268648A - Inter-network connector - Google Patents

Abstract

PURPOSE:To prevent a line use rate from being lowered and to reduce cost by transmitting call continuously to data transmission when the transmission is enabled with the same tariff and disconnecting the call after the transmission. CONSTITUTION:When an ISDN layer 1 control part A receives data from an ISDN line 3 and a D channel call control protocol control part 12 performs the call setting of a B channel, the time measurement of a monitor timer 16 is started and reception processing is performed. When the processing is completed, the measured time of the timer 16 is measured and held in the timer 16 as data transfer time and the timer 16 is reset. When a LAN interface part 10 receives data from a LAN 2a and it is not necessary to transmit the data to the line 3, it is decided whether the timer 16 is turned to time out or not and in the case of transmission, the timer 16 is reset by performing transmission processing after the time of the timer 16 is measured. When any data are not received later for fixed time, the timer 16 is stopped, the data transfer time and monitored time is transferred to a path information processing part 11b later, and the transmission processing is performed by a tariff arithmetic part 11c. Thus, the line use rate is improved and the cost is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection device between networks, and more particularly, to a plurality of local area networks (hereinafter referred to as "LAN") which are integrated service digital communication networks (hereinafter referred to as "I") based on CCITT Recommendation I series.
SDN ") to connect to each other
The present invention relates to an inter-network connection device for widening the AN area.

[0002]

2. Description of the Related Art Conventionally, when data is transferred between a plurality of networks connected to a general public network such as ISDN, an inter-network connecting device is provided between the general public network etc. and the network. Generally, not only data transfer between networks but also various information such as route information shared between network connection devices and management information of each network is transferred using the inter-connection devices.

Here, the route information is I which is a general public network.
Since there are multiple routes available in the SDN network, IS
The static routing method and the dynamic routing method are known as a method for selecting a route using this route information, which is information held by the inter-network connecting device at the connection point between the DN and the network.

In the static routing method, a route used in advance is fixedly registered in a table (hereinafter referred to as "routing table") in a storage medium, and when an unexpected failure occurs or a new terminal joins. In this method, the operator updates the routing table. Therefore, this static routing method
It is suitable for networks where terminal devices are not often added or removed.

On the other hand, the dynamic routing method is a method in which each inter-network connecting device periodically transmits route information to the other party and updates the routing table held by each inter-network connecting device. This dynamic routing method is suitable when there are many joining / leaving terminals.

Generally, in networks such as LANs (local area networks), frequent joining / leaving of terminal devices is performed. Therefore, a dynamic routing system for periodically updating route information is used. Route information will be exchanged.

By the way, management information transferred between networks includes, for example, the International Organization for Standardization (International Or
information standardized by ganization for Standardization), for example, a station connected to a network (hereinafter referred to as “manager”) that manages the entire network, and each station managed by a manager connected to the network (hereinafter referred to as “agent”). There is information to be sent.

Data transfer between the manager and the agent may be performed by the agent transmitting management information in response to an information request from the manager or by the agent transmitting management information to the manager regularly or irregularly. However, in either case, the inter-network connection device transmits / receives data to / from the ISDN line.

As described above, even when the information for managing the network is sent to the ISDN line or the like as in the case of transmitting the above route information or the above management information, the inter-network connecting device uses these information. Is transmitted using an information channel (hereinafter referred to as “B channel”),
Alternatively, it is transmitted using a control channel (hereinafter, referred to as “D channel”).

[0010]

However, when the above information is transferred using the B channel, the above information is frequently transmitted even if the data transmission carried out between the terminals is completed, so that a call is made. There is a problem that the communication cost increases because the connection cannot be disconnected.

On the other hand, in the LAN-to-LAN connecting device disclosed in Japanese Patent Laid-Open No. 4-54039, an invention is disclosed in which management information is transferred using the D channel.

FIG. 4a is a timing chart of the inter-LAN connecting device.

This LAN-to-LAN connecting device is a system for transmitting management information and the like by using information (hereinafter referred to as "user / user information") that the end user can arbitrarily use among message information of D channel. As shown in 4a,
When the data transfer between the LANs is completed, it is confirmed by using the monitoring timer that the data transfer is not performed for a certain period of time, and the call is forcibly disconnected when the monitoring timer times out.

However, since the data length of the user-user information is limited to several hundred bytes, it is necessary to divide the management information and repeat the transfer operation in order to exchange the necessary management information and the like. There is a problem of inefficiency. Further, since the call is forcibly disconnected due to the time-out of the monitoring timer, the data transfer is stopped despite the remaining time for which the data transfer is possible at the same charge, which is not efficient in terms of communication cost.

In view of the above, the present invention eliminates such a problem and prevents a decrease in line usage efficiency when transferring the above-mentioned route information and management information and reduces the communication cost associated with the transfer of the information. The purpose is to provide.

[0016]

In order to achieve the above object, according to the present invention, in an inter-network connection device for connecting at least two networks via a communication line having a control channel and an information channel, the information channel is provided. When performing data transmission between the networks by using, an arithmetic means for computing the amount of information that can be transmitted at the same charge after the end of a predetermined monitoring time from when there is no transmission data on the information channel until the line is disconnected ( 1 of FIG.
1c) and transmission processing means (11b in FIG. 1) for transmitting predetermined information that does not require immediacy in correspondence with the amount of information calculated by the calculation means.

[0017]

According to the present invention, when exchanging information that does not require immediacy among the route information and the management information between the networks that connect the networks via the line having the control channel and the information channel, the information channel is used. When the data transmission between the networks is completed by using the above, the amount of information that can be transmitted within the same charge is calculated using the calculation means, and if the information can be transmitted, the information channel is used. The data is transmitted between the networks by the transmission processing means, and the call is disconnected after the transmission of the information. As a result, it is possible to eliminate the call setting operation when transmitting the predetermined information, so that it is possible to prevent a decrease in the line usage efficiency and delete the communication cost charged when the information is transferred.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall structure of a network and the structure of an inter-network connecting device which is an embodiment of the present invention.

In this embodiment, a network layer (hereinafter referred to as "IP" (Internet Protocol)) that has functions such as time monitoring and connection establishment / disconnection, manages network addresses and exchanges route information. When bus type LANs (hereinafter, referred to as “Ethernet”) adopting the implemented IEEE802.3 CSMA / CD access method are connected to each other via an ISDN line,
An example of exchanging LAN route information between LAN-to-LAN connecting devices will be described.

As shown in FIG. 1, LAN2a and LAN2
b is the ISD via the LAN connection devices 1a and 1b, respectively.
The LAN interface unit 10, the ISDN / LAN data exchange processing unit 11, the D channel call control protocol control unit 12, the B channel circuit exchange control unit 13, and the ISDN layer 1 control are connected to the N line 3 and the LAN connection device 1a. It comprises a unit 14, a routing table 15, and a monitoring timer 16.

Here, the LAN interface unit 10
Performs assembling / disassembling of Ethernet packets and IP protocol processing, and the data received from the LAN 2a is I
The data is transmitted to the SDN / LAN data exchange processing unit 11 and the data received from the ISDN / LAN exchange processing unit 11 is transmitted to the LAN 2a according to the protocol.

The ISDN / LAN exchange processing unit 11 includes an exchange processing unit 11a, a route information processing unit 11b and a charge calculation unit 1.
1c, and the exchange processing unit 11a includes a LAN interface unit 10 and a D channel call control protocol control unit 1
2 or B channel circuit switching control unit 13 stores and exchanges data with each other, and also routes information processing unit 11
The route information is received from b and exchange processing is performed.

Here, the route information processing unit 11b uses the monitoring timer 16 to monitor the time required for data transfer between LANs (hereinafter referred to as "data transfer time (Tq)") and the monitoring timer after the data transfer is completed. Until the timer times out (hereinafter, "monitoring timer timeout time (T
k) ”) is received, the routing table 1
The time required to transmit the route information in 5 (hereinafter referred to as "route information transmission time (Tr)") is calculated, and the remaining time (hereinafter, referred to as "remaining time" at which the charge calculation unit 11c can transmit at the same charge)
“Remaining time (Tm)” is received, and both are compared to determine whether or not the route information can be transmitted within the remaining time (Tm). If the route information cannot be transmitted (Tm <Tr), the D channel call is made. When the call disconnection instruction can be issued to the control protocol control unit 12a and transmitted (Tm ≧ Tr), the route information is extracted from the routing table 15 and the exchange processing unit 11 is executed.
After transferring to a, a call disconnection instruction is issued.

Further, the charge calculation unit 11c receives the data transfer time (Tq) and the monitoring timer timeout time (Tk) from the route information processing unit 11b, and the remaining time (Tm).
Is calculated and returned to the route information processing unit 11b.

D channel call control protocol control unit 12
Performs the process of setting / maintaining / disconnecting the B-channel circuit switched call based on the data received from the ISDN / LAN exchange processing unit 11. At this time, the call disconnection process is performed after receiving a call disconnection instruction from the route information processing unit 11b.

The B-channel circuit switching control unit 13 uses the ISD
When data is received from the N / LAN exchange processing unit 11, it is sent to the ISDN line 3 via the ISDN layer 1 control unit 14 by processing according to the line exchange protocol, and when data is received from the ISDN layer 1 control unit 14. The data is sent to the ISDN / LAN exchange processing unit 11.

The ISDN layer 1 control unit 14 assembles the data received from the D channel call control protocol control unit 12 and the B channel circuit switching control unit 13 into an ISDN layer 1 frame and sends it to the ISDN line 3, and at the same time, the ISDN line 3 The ISDN frame received from is divided and sent to the D channel call control protocol control unit 12 and the B channel circuit switching control unit 13.

The routing table 15 is a table for storing route information, and is read and written by the route information processing unit 11b in the ISDN / LAN exchange processing unit 11.

The monitoring timer 16 has a data transfer time (T
q) and the monitoring time (Tk) are measured, and when the monitoring timer times out, the data transfer time (Tq) and the monitoring tie time (Tk) are transferred to the route information processing unit 11b.

Although the configuration of the inter-LAN connecting device 1a has been described above, the inter-LAN connecting device 1b has the same configuration and performs the same operation as described below, but here, for convenience of explanation, the inter-LAN connecting device is connected. The description will be continued using the device 1a.

FIG. 2 is a flow chart showing the outline of the main processing of the inter-LAN connecting device 1a.

First, the inter-LAN connecting device 1a is the ISDN.
Presence / absence of data reception (S1) from the ISDN line 3 in the layer 1 control unit 14 and the LAN interface unit 1
If the ISDN layer 1 control unit receives data from the ISDN line 3 (S1) by detecting the presence or absence of data reception (S5) from the LAN 2a in 0 (S1), D is started to start measurement of the data transfer time (Tq). After the time measurement of the monitoring timer 16 is started at the time when the channel call control protocol control unit 12 sets up the call for the B channel (S2), the IS
The DN data reception process is performed (S3), the measurement time of the monitoring timer 16 is measured at the time when the ISDN data reception process is completed, and this is held in the monitoring timer 16 as the data transfer time, and the measurement of the monitoring timeout time is started. Therefore, the monitoring timer 16 is reset (S4).

The LAN interface unit 10 is L
When data is received from the AN 2a (S5), LAN data reception processing is performed (S6), and it is determined whether or not to send data to the ISDN line 3 (S7).

If it is not necessary to send data to the ISDN line 3, the process proceeds to the judgment (S11) as to whether or not the monitoring timer 16 has timed out, and if data is to be sent to the ISDN line 3, S2. After starting the time measurement of the monitoring timer 16 in the same procedure as (S8), the ISDN data transmission process (S9) is performed, and the monitoring timer 16 is reset in the same procedure as S4 (S10).

Further, after resetting the monitoring timer 16 (S4, S10), if no data is received for a certain time, the monitoring timer 16 times out (S11). In this case, after stopping the monitoring timer 16 (S12). , The data transfer time (Tq) and the monitoring time (Tk) are transferred to the route information processing unit 11b.

After the route information processing unit 11b uses the charge calculation unit 11c to perform the route information transmission process (S13), which will be described in detail below, the route information processing unit 11b causes the D channel call control protocol control unit 12 to operate. The D-channel call control protocol control unit 1 is instructed to disconnect the circuit-switched call.
2 disconnects the call (S14).

Next, the route information transmission process (S13) performed by the route information processing unit 11b using the charge calculation unit 11c will be described in detail with reference to the flowchart shown in FIG.

First, when the route information processing unit 11b receives the data transfer time (Tq) and the monitoring time period (Tk) from the monitoring timer 16, it retrieves the route information from the routing table 15 and needs it when transmitting the route information. The route information transmission time (Tr) required to transfer the number of transmitted packets (hereinafter, referred to as “route information transmitted packet number (Pr)”) is calculated (S40 to S41).

At this time, the number of route information transmission packets (Pr)
Is the data amount of the route information extracted from the routing table 15 (hereinafter, “route information data amount (Dr)”).
Is divided by the amount of information (Dp) that can be transmitted in one packet (Pr = INT (Dr / Dp)
+1)) (S40), the number of packets of this route information transmission (P
r) is multiplied by the time required to send one packet (Tp) to calculate the time Tr required to send the route information (Tr
= Pr * Tp) (S41).

Next, the route information processing unit 11b transfers the data transfer time (Tq) and the monitoring time time (Tk) to the charge calculation unit 11c, and the charge calculation unit 11c displays the remaining time (Tk).
m) is calculated, and the calculation result is returned to the route information processing unit 11b.

That is, in the time chart of FIG. 4b, when Tn is a flat fee time and Ts is a time required for data transfer in the flat fee, the remaining time (Tm) is Tm.
= Tn-Ts-Tk can be calculated by the following calculation,
First, calculate Ts (Ts = mod (Tq / Tn))
After (S42), the remaining time (Tm) is calculated (Tm = Tn-Ts-Tk) (S43).

Next, in the route information processing section 11b, S41
The route information transmission time (Tr) calculated in step 3 and the charge calculation unit 11
The remaining time (Tm) received from c is compared (S4
4) If the remaining time is longer than the route information transmission time (Tm ≧ Tr), the route information transmission process is performed (S4).
5) Otherwise, (Tm <Tr) the information transmission is forgotten.

By the above series of processing, the remaining time (Tm)
It is possible to transfer the route information using, but the remaining time (T
If m) is shorter than the route information transmission time (Tr), the route information cannot be transmitted substantially.

However, the number of packets that can be transmitted using the remaining time (Tm) (hereinafter, "the number of packets that can be transmitted (P
The above problem can be solved by calculating "e)", and initially transmitting only Pe for the number (Pr) of route information transmission packets, and then transmitting the remaining packets.

Below, the number of packets that can be transmitted (P
Another route information transmission process performed using e) will be described with reference to FIG.

First, as in the previous example, the route information processing unit 11
b calculates the number of route information transmission packets (Pr) by using the data amount (Dr) of the route information (S5O). At this time, the transfer time is used as the criterion in the previous example, whereas the number of packets is used as the criterion in this example, so that it is not necessary to calculate the route information transmission time (Tr).

Next, as in the previous example, the charge computing unit 11c calculates the remaining time (Tm) (S51 to S52), and the route information processing unit 11b receiving the remaining time (Tm) calculates the remaining time (Tm). Time required to send one packet (T
Number of packets that can be transmitted by dividing by p) (Pe)
Is calculated (Pe = INT (Tm / Tp)) (S5
3).

Then, if the packet cannot be transmitted (Pe = 0), the process is terminated, but if the packet can be transmitted (Pe ≧ 1) (S54), the number of packets for transmitting route information (Pr) is set. The number of packets that can be transmitted (Pe) is compared (S55), and if all the packets can be transmitted (P55)
r ≦ Pe) All route information is transmitted (S56), and the address of the final transmission packet (hereinafter referred to as “final packet address (Adr)”) is initialized (Adr = 0) (Sr).
57).

If the number of packets for transmitting route information (Pr) is larger than the number of packets that can be transmitted (Pe) (Pr)
> Pe), first, the number of transmittable packets (Pe) out of the number of route information transmission packets (Pr) is first transmitted (S58),
The final packet address is stored (Adr = final address) (S59).

By performing the above processing, the remaining time (T
Even if m) is short, the route information can be transmitted.

Thus, in the above embodiment,
When the route information processing unit 11b receives the data transfer time (Tq) and the monitoring time period (Tk) from the monitoring timer 15, the route information transmission time (Tr) is calculated, and the charge calculation unit 1
When the remaining time (Tm) is longer than the route information transmission time (Tr) compared with the remaining time (Tm) received from 1c, the route information is transmitted, and then the route information processing unit 11
D channel call control protocol control unit 1 based on the instruction of b
When 2 disconnects the call, it is not necessary to place a call to transmit the route information, so that it is possible to prevent a decrease in the line usage efficiency and to eliminate the communication cost charged when the route information is transferred. .

Next, I
An embodiment for transferring the management information via the SDN network will be described with reference to FIG. For the sake of convenience of explanation, the same numbers are assigned to the components having the same roles as those in the previous example.

FIG. 6 is a block diagram showing the configuration of the inter-LAN connecting device 1a when the management information is irregularly transmitted from the agent 18 connected to the LAN 2b to the manager 17 connected to the LAN 2a.

In FIG. 6, the LAN connection device 1a is
When the management information transmitted from the agent 18 is received, the information is transmitted to the LAN interface unit 10 and I
It is stored in the storage unit 15 ′ via the SDN / LAN data exchange processing unit 11.

If the data transfer is performed, the management information is transferred after the end of the data transfer in the same manner as in the previous example, and after the transfer of the management information, the D channel call control is performed by the instruction of the management information processing unit 11b-2. The protocol control unit 12 disconnects the call.

Further, the LAN-to-LAN connecting device 1b transmits the management information to the manager 17 by performing the reverse procedure described above.

As described above, when transferring the management information between the manager 17 and the agent 18, it is not necessary to place a call to transmit the management information, so that it is possible to prevent the deterioration of the line use efficiency and to manage the management information. The communication cost charged at the time of transfer can be deleted.

The manager 17 and the agent 1
In order to periodically transmit the management information between the eight, when the data transmission is performed, the method shown in the above embodiment is applied, and when the data transmission is not performed for a certain period,
Call setup can also be performed using the B channel.

Furthermore, in the above embodiment, the application of the present invention has been described for the route information and the management information, but the present invention is applicable not only to the above information but also to various information which does not require relatively immediacy. Can be applied, and it is possible to prevent a decrease in the line use efficiency and delete the communication cost charged when transferring the information.

[0061]

As described above in detail, according to the present invention, the immediacy of the route information and the management information between the networks connecting the networks via the line having the control channel and the information channel is not required. When exchanging predetermined information, when the data transmission between networks using the information channel is completed, the amount of information that can be transmitted within the same charge is calculated using the calculation means, and the information is When the information can be transmitted, the information is transmitted using the transmission processing means following the data transmission between the networks performed using the information channel, and the call is disconnected after the information is transmitted. As a result, there is no need to place a call to transmit the predetermined information, which has the advantages of preventing a decrease in line usage efficiency and eliminating the communication cost charged when transferring the management information.

Further, when data transmission between networks is not performed for a certain period of time, predetermined information can be exchanged by also using a method for call setting.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a LAN-to-LAN connecting device that is an embodiment of the present invention.

FIG. 2 is a flowchart showing a main process of the LAN-to-LAN connecting device that is an embodiment of the present invention.

FIG. 3 is a flowchart showing route information transmission processing during the main processing shown in FIG.

FIG. 4 is a diagram showing a route information transmission timing in the case of the conventional method (FIG. 3a) and the present invention (FIG. 4b).

5 is a flowchart showing an example of another route information transmission process during the main process shown in FIG.

FIG. 6 is an LA when the present invention is applied to transmission of management information.
The block diagram which shows the structure of the N connection device.

[Explanation of symbols]

1a, 1b LAN connection device 2a, 2b LAN
3 ISDN line 10 LAN interface section 11 ISDN / LA
N data exchange processing unit 11a exchange processing unit 11b route information processing unit 11c
Charge calculation unit 12 D channel call control protocol control unit 13 B channel circuit switching control unit 14 ISDN layer 1 control unit 15 routing table 16 monitoring timer 17 manager 18 agent

Claims (1)

[Claims] 1. An inter-network connection device for connecting at least two networks via a communication line having a control channel and an information channel, wherein when performing data transmission between the networks using the information channel, the information A computing unit that computes the amount of information that can be transmitted at the same charge after the end of a predetermined monitoring time from when there is no transmission data on the channel until the line is disconnected, and the immediacy corresponding to the amount of information computed by the computing unit. An inter-network connection device comprising: a transmission processing unit that transmits predetermined information that does not require the transmission.