JPH11355345A - Inter-lan connector and inter-lan connection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inter-LAN connector and inter-LAN connection system where a load is relieved, limit on the number of connectable points is less and data are relayed at a high transfer rate and at a low cost. SOLUTION: The inter-LAN connector that relays data among pluralities of networks consists of a switching hub H, stores a virtual network address for each server being a device of relay destination, replies a MAC address of the server of the relay destination corresponding to the virtual network address when a medium access control MAC address of the virtual network address is requested and relays data not addressed to its server through bridge processing when receiving the data whose destination MAC address indicates other server.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a LAN such as a switching hub for relaying data between a plurality of networks.
The present invention relates to a (Local Area Network) connection device and an LAN connection system using the LAN connection device.

[0002]

2. Description of the Related Art Various configurations have been proposed as a data communication system for accessing a server from terminals at a plurality of bases and connecting the LAN where the server exists and a WAN (Wide Area Network). ing.

For example, in the system shown in FIG. 4, one relay router 10 is connected to a dedicated router Y connected to each of a plurality of terminals P via a dedicated line K, and is connected to a plurality of servers S. It is configured to connect between a plurality of terminals P and the server S by using them.

In the system shown in FIG. 5, a plurality of terminals P and a server S are connected by using one relay router 20 for a terminal P at one base.

[0005]

In the system shown in FIG. 4, since one relay router 10 relays data between a large number of terminal P-servers S, the load on the relay router 10 increases. There are issues.

On the other hand, in the system shown in FIG. 5, since a plurality of relay routers 20 are used, the load is distributed. Is limited by the number of available network addresses.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and can reduce a load, reduce the number of connectable bases, and relay data at a low cost and at a high speed. And a LAN connection system.

[0008]

According to the present invention, there is provided an inter-LAN connecting apparatus which performs relaying of data between a plurality of networks.
An N-to-N connection device that holds a virtual network address for each relay destination device, and when a MAC address of a certain virtual network address is requested, changes the MAC address of the relay destination device corresponding to the virtual network address. In response, if data having a destination MAC address other than the own device is received, the data is relayed by bridge processing.

When notifying the path information to another communication device, a virtual network address corresponding to the relay destination device may be notified as a relay network address of data addressed to a certain relay device.

[0010] When the destination MAC address is the own device, and data which is the network address of the relay destination device having the destination network address is received, the data is routed to the relay destination device and relayed. A virtual network address corresponding to the relay destination device may be notified to the communication device that has transmitted the data to the relay device as the network address of the data relay destination device addressed to the relay destination device.

[0011] A virtual network address may be stored in advance for each relay destination device.

When the virtual network address is not held for the relay destination device, the relay destination device
An unused virtual network address may be allocated and held.

The LAN connection system according to the present invention has
It has an inter-AN connecting device, and another inter-LAN connecting device connected to the inter-LAN connecting device by a LAN, wherein a private network address is allocated to the LAN.

[0014] As a virtual network address used in the LAN connection device, a private network address not allocated to the LAN connection device may be used.

[0015]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 shows the L of the present invention.
FIG. 1 is a configuration diagram illustrating a data communication system using a switching hub that is an inter-AN connection device.

As shown in FIG. 1, a switching hub H, which is an inter-LAN connecting device of the present invention, includes a relay destination network NW1 in which a server S exists, and a network NW2 in which a relay router T for receiving relay data exists. L between
AN connection is performed. Each of the relay routers T1, T2,... Is a dedicated router Y1, Y2 connected to a terminal P1, P2,.
.. Are connected via dedicated lines K1, K2,.
Here, a private network address is assigned to the network NW2 as a network address,
In FIG. 1, other networks NW1, NW3, NW4,.
・ Assign a global network address as a network address.

The switching hub H is connected to the network NW
1 as well as the network address, MAC (Media Access Control) address, and virtual network address of each of the servers S1, S2,... Which are data relay destination devices. Since the virtual network address is an address that the relay router T that relays data to the switching hub H recognizes as a new relay destination of data, a private network address that is not actually used in the address of the network NW2 is used.

In the switching hub H, a virtual network address may be stored in advance for each relay destination device, or if no virtual network address is stored for the relay destination device, , An unused virtual network address may be allocated and held. In addition, each server S1, S
.. Need not recognize that such a virtual network has been allocated to the own device in the switching hub H.

When a request for a MAC address for the virtual network address is made, the switching hub H responds with the MAC address of the server S corresponding to the virtual network address.

The switching hub H has a destination MAC
When receiving the data whose address is the own device and the destination network address is the network address of the server S, the data is routed to the relay destination device and relayed, and the data is transmitted to the own device. The router T is notified of a virtual network address corresponding to the server S as a relay destination network address of data addressed to the server S. Thus, when the router T transmits data addressed to the server S from the next time, the router T requests the MAC address for the virtual network address to transmit the data to the device of the notified virtual network address, Data is transmitted using the address as the destination MAC address.

FIG. 2 is a diagram for explaining the flow of routing (path control) when transmitting data addressed to a server from a terminal, and FIG. 3 is an explanatory diagram showing a routing table held by the relay router T. In FIG. 2, IP (Internet Protocol) is used as a network address.
Address, and set the IP address of the destination server S1 to (X
X.XX.XX.1), the virtual IP address is (10.0.0.2), the IP address of the source terminal P1 is (YY.YY.YY.1), and the IP address of the switching hub H is (10.0.0.1). I do.

First, data (destination IP = XX.XX.XX.1, source IP = YY.YY.YY.1) is transmitted from the terminal P1 to the dedicated router Y.
1. Sent to the relay router T1 via the dedicated line K1 (route L1).

The relay router T1 initially holds a routing table as shown in FIG. 3A, and has the route information that the data relay destination is the switching hub H. Is received, a packet requesting the MAC address of the switching hub H is broadcast by, for example, ARP (Address Resolution Protocol) (route L2).

The switching hub H that has received this sends its own MAC address and responds to the relay router T1 (route L3).

Since the destination MAC address is the MAC address of the switching hub H, the relay router T1 relays data to the switching hub H (route L4).

The switching hub H receiving the data,
Information about the destination network address of the data (the address of the server S1) is searched, and the data is relayed to the server S1 by a routing process (route L5).

At the same time, the switching hub H transmits, for example, an ICMP (Internet Control
ol Message Protocol) packet, the relay destination to the server S1 is the virtual IP address (10.0.0.
2) (route L6). As a result, the relay router T1 holds the routing table shown in FIG. 3B, and the network address of the relay destination of the data addressed to the server S1 is the virtual IP address notified.
Recognize as an address (10.0.0.2).

Thereafter, data (destination IP = XX.XX.XX.1, source IP = YY.YY.YY.1) is transmitted from the terminal P1 to the dedicated router Y.
1. When sent to the relay router T1 via the dedicated line K1 (route L7), the relay router T broadcasts a packet requesting a MAC address for the virtual IP address (route L8).

Upon receiving this request, the switching hub H responds to the relay router T1 with the MAC address of the server S1 (route L9).

Since the destination MAC address is the address of the server S1, the relay router T1 relays data to the server S1 (route L10).

When the relay router T1 acquires the MAC address corresponding to the network address and holds the acquired MAC address, there is no need to broadcast the request packet.

The switching hub H has information on which interface to relay to for each MAC address, and when there is input of data whose destination MAC address is not itself, the switching hub H searches this information and sends it to an appropriate interface. Bridge processing and relaying (route L11). Therefore, when there is an input of data addressed to the MAC address of the server S, the data is directly relayed to the interface without performing the routing process using the network address.

As shown in FIG. 1, a plurality of networks NW3, networks NW4,.
Exist, the respective networks NW3, NW
4 perform the same processing in data communication from the terminals P1, P2,. The switching hub H holds a network address, a MAC address, and a virtual network address for each server S, which is a relay destination device, and performs the same processing on data addressed to each of the servers S1, S2,. Further, an address that is not used in the network NW2 is reserved as a virtual network address, which is allocated to each server, and notified to each relay router T.

According to the present invention, when data addressed to the MAC address of the server S is input, bridge processing is performed directly to the interface without performing routing processing using a network address, and relaying is performed. Data can be relayed at reduced speed. As a result, the relay performance can be improved, and a data communication system that can be connected to more networks can be constructed.

Also, since more data can be relayed, the amount of data that cannot be relayed and is discarded in a system having a large number of networks and a large data communication volume can be reduced.

Even if the number of bases increases, a private network address may be assigned to the relay router T, so that the number of connectable bases is not limited to the number of LAN network addresses of the server S. .

The present invention is not limited to the above embodiment, and various changes can be made within the scope of the technical matters described in the claims. For example, FIG.
It is also possible to use the dotted line portion indicated by NW2 as one relay device. Further, the notification of the relay destination network address for the data addressed to the server to the relay router T may be performed using, for example, a RIP (Routing Information Protocol) packet.

[0038]

According to the present invention, when a request for a MAC address for a virtual network address is made, the MAC address of the device corresponding to the virtual network address is returned, and data is transmitted to the device corresponding to the virtual network address. Since the relay is performed after the bridge processing, the load at the time of the relay is reduced, and the data can be relayed at a high speed. As a result, the relay performance can be improved, and a data communication system that can be connected to more networks can be constructed.

Even if the number of bases increases, a private network address may be assigned to the relay router connected to the switching hub via LAN. Therefore, the number of bases that can be connected is not limited to the number of network addresses. Absent.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a data communication system using a switching hub which is an inter-LAN connection device of the present invention.

FIG. 2 is a diagram specifically illustrating a flow of routing (route control) when data addressed to a server is transmitted from a terminal.

3A and 3B are explanatory diagrams showing a routing table held by the relay router T, wherein FIG. 3A shows an initial state, and FIG. 3B shows a state after a notification is received from a switching hub.

FIG. 4 is a configuration diagram showing a conventional data communication system.

FIG. 5 is a configuration diagram showing another conventional data communication system.

[Explanation of symbols]

 K: Dedicated line H: Switching hub P: Terminal S: Server T: Relay router Y: Dedicated router NW1: Network NW2: Network NW3: Network NW4: Network

Claims (7)

[Claims] An inter-LAN connecting device for relaying data between a plurality of networks, wherein a virtual network address is held for each relay destination device, and when a MAC address of a certain virtual network address is requested. Responding to the MAC address of the relay destination device corresponding to the virtual network address, and, when receiving data whose destination MAC address is not the own device, relaying the data by bridge processing. . 2. The method according to claim 1, wherein when notifying the routing information to another communication device, a virtual network address corresponding to the relay destination device is notified as a relay destination network address of data addressed to a certain relay destination device. LAN described in
Connection device. 3. When data having a destination MAC address of the own device and a network address of a relay device having a destination network address is received, the data is routed to the relay device and relayed. And transmitting a virtual network address corresponding to the relay destination device as a network address of the relay destination device of the data addressed to the relay destination device to the communication device that has transmitted the data to the own device. Item 3. An inter-LAN connection device according to item 2. 4. The apparatus according to claim 1, wherein the virtual network address is held in advance for each of the relay destination apparatuses.
4. The LAN connection device according to any one of Items 3 to 3. 5. The method according to claim 1, wherein when no virtual network address is held for the relay destination device, an unused virtual network address is allocated and held for the relay destination device. 5. The inter-LAN connection device according to any one of items 1 to 4. 6. The LAN connection device according to claim 1, further comprising: a LAN connection device connected to the LAN connection device and another LAN connection device.
A private network address is allocated to the LAN. 7. A private network address not assigned to an inter-LAN connecting device is used as a virtual network address used in the inter-LAN connecting device according to any one of claims 1 to 5. The LAN connection system according to claim 6, wherein: