JP2002026983A - Data transmission method and data transfer system, and recording medium for recording program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To distribute a function load and a processing load of a PE unit and to relieve a control load and resource consumption in a provider network. SOLUTION: In the case that data sent from a terminal (e.g. a C101a) belonging to a network group the same as itself exist in data including information of a destination terminal (e.g. a C102a) received by data transmission reception means P101-P104 to which at least one terminal (C101a-C101b, C102a-C102b, C103a-C103b, and C104a-C104b) belonging to a network group is connected, the data are received from the data transmission reception means P101, the data are transferred to the data transmission reception means P102 to which the destination terminal C102a is connected on the basis of the information of the destination terminal C102a and the transmission reception means P102 outputs the data to the destination terminal C102a by a data assignment means R101 provided to each network group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a data transfer method and a data transfer device, and a recording medium on which a program is recorded. The present invention relates to a transfer method, a data transfer device, and a recording medium on which a program is recorded.

[0002]

2. Description of the Related Art Conventionally, when data transfer is performed between a plurality of customer networks existing via a provider network applied to the Internet or an intranet, as shown in FIG. , Virtual links L102 to L107 that can transmit and receive packets are set,
Customer network via these virtual links L102-L107
VPN (Virtual Priv) that connects M101 to M104 mutually
ate Network).

In this type of data transfer method, for example, when packet data is transferred from the customer network M101 to the customer network M102, the packet data is transferred to the CE of the customer network M101.
(Customer Edge) Device C101 to lower layer link D101
Is transmitted to the PE (Provider Edge) device P101 of the provider network N101 via the network.

The PE devices P101 to P104 are a type of router provided in the provider network N101 for each of the customer networks M101 to M104, and each of the customer networks M101 to M104 is connected via lower layer links D101 to D104. The packet data is received from the CE devices C101 to C104, and is delivered to the virtual routers R101 to R104 provided in the respective devices. In addition, the same provider network N101
The packet data transferred from the other PE devices is received and delivered to the virtual routers R101 to R104 provided in each.

[0005] The CE devices C101 to C104 correspond to the PE devices P101 to P101, respectively.
It is a type of router in the customer networks M101 to M104 connected to P104, and transmits packet data to connected PE devices P101 to P104 via lower layer links D101 to D104.
Conversely, it receives the packet data transmitted from the PE devices P101 to P104.

[0006] The packet data received by the provider network N101 is encapsulated with a packet header attached to the PE device P101 at the destination. This packet header contains
The PE device information of the transfer destination of the packet data is recorded, whereby the transfer destination of the packet data is recognized in the provider network N101 without referring to the contents of the packet data.

[0007] The virtual links L102 to L107 transmit the encapsulated packet data to each of the PE devices P101 to P104 (in this case, the PE device P102) of the provider network N101 based on the transfer destination information recorded in the packet header. ) Is a transfer path. In the example shown in FIG. 9, no other device such as a router is interposed between the PE devices P101 to P104, but another device such as a router is interposed between the PE devices P101 to P104. In some cases.

Each of the PE devices P101 to P104 is provided with a virtual router R101 to R104, respectively. The virtual router has a function of managing a packet transfer table related to a specific VPN, and a function of transferring a VPN packet based on the packet transfer table. In the transfer destination PE device (in this case, the PE device P102), the packet head is removed by the virtual router (in this case, the virtual router R102), the contents of the original packet data are referred to, and the destination customer network of the transfer destination customer network is referred to. The data is transferred to the CE device (in this case, the CE device C102 of the customer network M102).

Since this transfer path is unique to the VPN, the virtual routers R101 to R104 have a packet transfer table defining a transfer path for each VPN, and based on the contents of the transfer table, Is transferred. Details of this method can be found in the article “BGP / MPLS” disclosed on the Internet website “www.ietf.org”.
They are listed in the file "rfc2547.txt" of VPN _s ".

Note that C connected to the PE devices P101 to P104
The number of E devices C101 to C104 is not limited to one, and may be connected to a plurality of CE devices as shown in an example in FIG. For example, each CE device C1 connected to the PE device P101
01 _a ~C101 _n are different from each VPN _(VPN a ~VP
N _n ), the virtual router R101 of the PE device P101 functions individually for each VPN.

[0011]

However, such a conventional data transfer method has the following problems.

First, the problems of the PE devices P101 to P104 are as follows.

1) The PE device has a plurality of different V
When accommodating CE devices belonging to PNs (tentatively, VPN ₁ , VPN ₂ ,..., VPN _m ), a virtual router for each VPN must be provided. In this case, it is necessary to manage m packet transfer tables by one PE device. For this reason, there is a problem that a functional load per PE device is large.

2) In order to manage the m packet transfer tables, the PE device must perform a routing protocol process on all the accommodated CE devices. For this reason, there is a problem that the processing load of one PE device is large. In this case, if a failure occurs in the routing protocol processing of one of the CE devices and a load is applied to the routing protocol processing of the PE device, the routing protocol processing with all the CE devices accommodated by the PE device is performed. There is a problem that it may have an adverse effect.

Next, problems of the provider network N101 are as follows.

The provider network N101 requires n virtual routers when the number of PE devices accommodating the CE devices belonging to the VPN ₁ is n. Also, since the virtual routers need to exchange routing information, n (n-1) / 2 routing protocol sessions between the virtual routers are required. Further, since the virtual routers transfer packet data, the virtual link between the virtual routers is n (n-1) / 2.
Required.

Therefore, 1) the provider network N101 is 1
A routing protocol session of the order of the square of the number of virtual routers is executed per VPN. Therefore, there is a problem that the state is easily affected by the state of the link in which the routing protocol session is performed, and the routing tends to be unstable.

2) The provider network N101 needs to set a virtual link of the order of the square of the number of virtual routers per VPN. Therefore, the load for controlling the virtual link increases.

For example, when an LSP (Label Switched Path) is used as a means for realizing a virtual link, a session for controlling the LSP needs to be executed between virtual routers.
There is a problem that the load is large because the order is the square of the number of virtual routers.

Also, it is necessary to assign a label to each of the LSPs as virtual links, but since the total number is on the order of the square of the number of virtual routers,
There is a problem of poor resource efficiency.

The present invention has been made in view of such circumstances, and conventionally, a VPN is provided to each PE device in a provider network.
By integrating the functions of the virtual routers provided by the number of VPNs into the provider network by the number of VPNs, the functional load and the processing load of the PE device are dispersed, and the control load and the control load of the provider network are reduced. It is an object to provide a data transfer method and a data transfer device capable of reducing resource consumption, and a recording medium on which a program is recorded.

[0022]

Means for Solving the Problems In order to achieve the above object, the present invention takes the following measures.

That is, according to the first aspect of the present invention, at least one terminal belonging to a certain network group is connected, and a plurality of data receiving means for receiving data transmitted from the terminal together with destination information of the data; Data transfer means for transferring the data received by the means based on the network group to which the source terminal belongs, and a transfer destination of the data transferred from the data transfer means, provided for each network group and transferred. Data allocating means for allocating and transmitting the data transferred based on the destination information of the data, and at least one terminal belonging to a certain network group, which is a destination of the data allocated and transmitted by the data allocating means, is connected. And allocates the transmitted data to the connected terminal And a plurality of data transmitting means for transmitting to the terminal belonging to the network group and the same network group to which the terminal belongs.

Therefore, in the data transfer apparatus according to the first aspect of the present invention, data can be transferred to terminals belonging to the same network group via the data transmitting means by the data allocating means provided for each network group. it can.

According to the invention of claim 2, at least one terminal belonging to a certain network group is connected, and a plurality of data receiving means for receiving data transmitted from the terminal together with data transmission destination information; Data transfer means for transferring received data based on the network group to which the source terminal belongs; and a transfer destination of the data transferred from the data transfer means, provided for each network group, and the transferred data. Data allocating means for allocating and transmitting the data transferred based on the transmission destination information, and at least one terminal belonging to a certain network group, which is a destination of the data allocated and transmitted by the data allocating means, Allocated data is transmitted based on the destination information of the connected terminals. And a plurality of data transmitting means for transmitting to the terminal.

Therefore, in the data transfer apparatus according to the second aspect of the present invention, data can be transferred to terminals belonging to the same network group via the data transmitting means by the data allocating means provided for each network group. it can.

According to the third aspect of the present invention, a plurality of connection means to which at least one terminal belonging to a certain network group is connected, and data provided from each of the connection means and transmitted from the terminal together with data transmission destination information are received. Data receiving means, provided in each connection means, and data transfer means for transferring data received by the data reception means of the same connection means based on the network group to which the source terminal belongs; A data allocating unit that is provided in any one of the connection units and that is a destination of the data transferred from the data transfer unit and that allocates and transmits the transferred data based on destination information of the transferred data; Means, and a destination of data allocated and transmitted by the data allocating means provided in each connection means. The transmitted data, and a data transmission means for transmitting to the terminal based on the destination information of the terminal own connection means is connected.

Therefore, in the data transfer apparatus according to the third aspect of the present invention, data is transferred to terminals belonging to the same network group via the data transmitting means by the data allocating means provided for each network group. be able to.

According to a fourth aspect of the present invention, in the data transfer apparatus according to the third aspect of the present invention, the number of data allocating means is smaller than the number of a plurality of all connecting means and all the connecting means for each network group. Prepare for connection means.

Therefore, in the data transfer apparatus according to the fourth aspect of the present invention, any one of the plurality of connection means includes a data allocating means provided for each network group,
With this data allocating means, data can be transferred to terminals belonging to the same network group via the data transmitting means.

According to the fifth aspect of the present invention, in the data including the information of the destination terminal, which is received by the plurality of data transmitting / receiving means connected to at least one terminal belonging to a certain network group, If there is data transmitted from a terminal belonging to the network group, the data is received from the data transmission / reception means, and the data is transferred to the data transmission / reception means connected to the destination terminal based on the information of the destination terminal. And a data allocating means provided for each network group for outputting data from the data transmitting / receiving means to the destination terminal.

Therefore, in the data transfer apparatus according to the fifth aspect of the present invention, data can be transferred to terminals belonging to the same network group via the data transmission / reception means by the data allocating means provided for each network group. it can.

[0033] According to the invention of claim 6, at least one terminal belonging to a certain network group is connected, and a plurality of data receiving means for receiving data transmitted from the terminal together with destination information of the data; Data transfer means for transferring the received data based on the network group to which the source terminal belongs and the destination information; and a transfer destination of the data transferred from the data transfer means, which belongs to a certain network group. A plurality of data transmission means connected to at least one terminal and transmitting data transferred from the data transfer means to terminals belonging to the same network group as the network group to which the source terminal belongs among the connected terminals; And

Therefore, in the data transfer apparatus according to the present invention, the data transmitted from the terminal belonging to a certain network group is transferred to the terminal belonging to the same network group via the data transmitting means. Can be.

According to the seventh aspect of the present invention, at least one terminal belonging to a certain network group is connected, data including transmission destination information transmitted from the terminal is received by the data receiving means, and received by each data receiving means. The transferred data is transferred based on the network group to which the source terminal belongs, and based on the destination information of the transferred data, the transferred data is allocated and transmitted by data allocating means provided for each network group. ,
The data allocated and transmitted by the data allocating means is
Any one of a plurality of data transmission means connected to at least one terminal belonging to a certain network group
And transmits to the terminal based on the transmission destination information among the terminals to which the terminal is connected.

Therefore, in the data transfer method according to the seventh aspect of the present invention, data can be transferred to terminals belonging to the same network group via the data transmitting means by the data allocating means provided for each network group. it can.

According to the invention of claim 8, at least one terminal belonging to a certain network group is connected, and data transmitted from the terminal is received by a plurality of data receiving means together with data transmission destination information. The received data is transferred based on the network group to which the source terminal belongs and the destination information, and the transferred data is transmitted by at least one of a plurality of data transmitting means connected to at least one terminal belonging to a certain network group. Via any one of the above, transmits to a terminal belonging to the same network group as the network group to which the source terminal belongs.

Therefore, in the data transfer method according to the invention of claim 6, data transmitted from a terminal belonging to a certain network group is transferred to terminals belonging to the same network group via data transmission means. Can be.

According to the ninth aspect of the present invention, there is provided a recording medium storing a program for controlling a data transfer device, wherein the program is received by a plurality of data transmitting / receiving means connected to a computer at least one terminal belonging to a certain network group. In the data including the information of the destination terminal, if there is data transmitted from a terminal belonging to the same network group as the network group specified in advance, the data is acquired from the data transmitting / receiving means, Based on the information of the data transmission destination terminal, the data transmission / reception means to which the transmission destination terminal is connected transfers the data, and further outputs the data from the data transmission / reception means to the transmission destination terminal.

Therefore, in the recording medium according to the ninth aspect of the present invention, the data transmitted from the terminal belonging to the same network group as the network group specified in advance is transmitted to the terminal belonging to the same network group via the data transmitting / receiving means. Can be forwarded to

[0041]

Embodiments of the present invention will be described below with reference to the drawings.

In the drawings used in the description of the following embodiments, the same parts as those in FIG. 9 are denoted by the same reference numerals.

(First Embodiment) A first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a configuration diagram showing an example of a data transfer apparatus to which the data transfer method according to the first embodiment is applied, and is an example in which a provider network N101 handles one VPN.

This embodiment is different from the prior art configuration shown in FIG. 9 in that the provider network N101
That is, only one virtual router is provided for each PN. Therefore, the description here will focus on the different parts.

[0046] That is, in the example shown in FIG. 1, the provider network N101 since handling only one VPN (eg. To VPN _1), first, as a PE device that functions as a virtual router for this VPN ₁ , PE device P101, and a virtual router is assigned to this PE device P101.
R101 is provided. And the other PE devices P102 to P104 are VP
Not provided with the virtual router for N _1.

As described above, the virtual router R101 for the VPN ₁ provided solely in the provider network N101 exchanges routing information with the customer networks M101 to M104 with respect to each of the CE devices C101 to C104 belonging to the VPN _1. I do. In other words, each CE device C101 belonging to VPN ₁
To C104 need only exchange routing information with the virtual router R101 for the provider network N101.

That is, the virtual router R101 is a CE device directly connected to the PE device P101 provided therein.
For C101, routing information is exchanged via lower layer link D101. In addition, P
The routing information is exchanged with the CE devices C102 to C104 to which the E device P101 is not directly connected as described below.

For example, in the case of the CE device C102, the PE device P1
The routing information is exchanged via the virtual link L102 between 01 and the CE device C102, and the lower layer link D102. Therefore, the PE device P102 that does not have the virtual router for VPN ₁
The L102 and the lower layer link D102 are interconnected by a lower layer transfer process. The specific implementation method will be described later.

It should be noted that the CE devices C103 and C104
02, and the PE devices P103 and P104 are the same as the PE device P102, and thus description thereof is omitted.

The lower layer links D101 to D104 are PE devices.
P101 to P104 and CE devices C101 to C104 are connected, and for example, ATM (Asynchronous Transfer Mode) or FR (Fr
This can be realized by existing data link layer technologies such as ame relay).

The virtual links L102 to L104 are terminated at the PE device, and are, for example, LSP (Label Switched Path).
It is realized by existing packet tunnel technology such as IP and IP in IP.

Next, the PE having the virtual router R101
The configuration of the device P101 will be described using a configuration example shown in FIG.

In this embodiment, the PE device P101 comprises a customer interface C201, a lower layer processing unit 201, a VP
N transfer table 202, provider router function unit 203, virtual router function unit R201, provider interface P2
01 to P203.

The customer interface C201 is a CE device.
An interface that accommodates C101 in the lower layer link D101, has a function of transmitting and receiving _one VPN packet to and from the CE device C101, and transmits _one VPN packet to the lower layer processing unit 20.
It has a function to transfer it to 1. FIG. 2 is an example.
Although a configuration including only one customer interface C201 is shown, an arbitrary number of customer interfaces may be provided.

The lower layer processing section 201 performs the following. 1) VP received from customer interface C201
For N ₁ packet with reference to the VPN forwarding table 202, and passes into the appropriate virtual router function unit R201. 2) Pass the VPN ₁ packet received from the virtual router function unit R201 to an appropriate provider interface (any of the provider interfaces P201 to P203).
3) VPN received from provider interface (any of provider interfaces P201 to P203)
_One packet is passed to an appropriate virtual router function unit R201 with reference to the VPN transfer table 202. 4) The VPN ₁ packet received from the virtual router function unit R201 is passed to an appropriate customer interface C201. 5)
Provider interface (provider interface
The packet received from any of P201 to P203) is passed to the provider router function unit 203. 6) The packet received from the provider router function unit 203 is transferred to an appropriate provider interface (provider interface P201).
To P203). The virtual router function unit R201 implements the function of a virtual router as described in the related art with respect to one VPN ₁ . Although only one virtual router function unit R201 is shown in FIG. 2 as the virtual router function unit, when the PE device P101 supports a plurality of VPNs, a virtual router function unit is provided for each VPN. . A specific configuration example of the virtual router function unit R201 will be described later.

[0057] Provider interfaces P201, P202, P2
03 is an interface that accommodates virtual links L102, L103, and L104, respectively, and transmits and receives packets to and from the other PE devices P102, P103, and P104 in the provider network N101 via the virtual links L102, L103, and L104, respectively. In addition, the packet is transferred to the lower layer processing unit 201. FIG. 2 shows the provider interface
Although P201, P202, and P203 are shown, the present embodiment may include an arbitrary number of provider interfaces.

The provider router function unit 203 has a function as a router in the provider network N101 and a control function for setting / release of the virtual links L102, L103, L104. For example, as shown in FIG. Department
301, a packet transfer table 302, a routing protocol processing unit 303, a virtual link control unit 304, and a VPN topology management unit 305.

The packet processing unit 301 refers to the packet transfer table 302 for the destination address of the packet passed from the lower layer processing unit 201 of the PE device P101, and provides a transfer destination provider interface (provided by the provider interfaces P201 to P203). Is determined, and the packet is transferred to the lower layer processing unit 201 of the transfer destination, thereby transmitting the packet via the provider interface (any of the provider interfaces P201 to P203) as the transfer destination. Having. Less than,
Such a transfer method is called “packet transfer”.

The contents of the packet transfer table 302 are managed by the routing protocol processing unit 303. The specific configuration is, for example, as shown in FIG. 6, similarly to a conventional router.

FIG. 6 shows an example of the packet transfer table 302. The packet transfer table 302 has a four-dimensional data sequence, that is, a destination prefix 701, next-stage information 702, and a transmission interface identifier 70.
3. It is composed of a transmission link identifier 704.

The column of the destination prefix 701 is used to search for a matching destination prefix for the destination address of the packet transmitted by the router. In addition,
The prefix is a search condition for partially searching and narrowing down.

The column of the next-stage information 702 is for obtaining the address information of the next-stage router to which the received packet matched in the search of the destination prefix is to be transferred, and the value is previously entered based on the routing information. Keep it.

The column of the transmission interface identifier 703 is for obtaining a value for identifying an interface to which a packet to be transferred is to be transmitted, and the value is previously entered based on the routing information.

The column of the transmission link identifier 704 is used to enter a value for identifying a lower layer link or a virtual link corresponding to the transmission interface.

The routing protocol processing section 303 follows the packet processing section 30 according to various routing protocols.
It exchanges routing information with other routers via 1 and manages the contents of the packet transfer table 302. The various routing protocols mentioned here are, for example, BGP4
(Border Gateway Protocol 4), OSPF (Open Shor
test Path First). Note that the files (rfc1771.txt and rfc2178.t
xt) is the Internet homepage "www.ietf.org"
It can be downloaded from. In addition, the other routers here are PE devices P101 to P104 and PE devices P101 to P101.
A router (not shown) between P104 corresponds to this.

The virtual link control unit 304 is based on the routing information held by the routing protocol processing unit 303 and the placement information of the virtual router R101 held by the VPN topology management unit 305, and the other PE devices P102 to P104 in the provider network N101. Controls the setting / release of the virtual links L102, L103, L104 between the virtual link L102, L103, and L104. As a control means, an existing tunnel control protocol can be applied. For example, if a virtual link is realized by LSP, LDP (Label Distribution
Protocol) and RSVP (resource ReSerVation Protocol)
ol) may be used, or if a virtual link is realized by another tunneling method, a tunnel control protocol corresponding thereto may be applied.

When such a tunnel control protocol is executed, the virtual link control unit 304
In order to communicate with P102 to P104, a protocol message is transmitted and received via the packet processing unit 301.

The VPN topology management unit 305 holds the arrangement information of the virtual router R101 of the PE device P101 in the provider network N101. For example, in a VPN configuration as shown in FIG. 1, "virtual router R1 of VPN ₁ "
01 is located in the PE device P101 ".

As means for setting such arrangement information in the VPN topology management unit 305, the PE devices P101 to P104
This may be manually set, or when the arrangement information of the virtual router R101 is added to the existing routing protocol, the information may be obtained from the routing protocol processing unit 303. Alternatively, as a setting by a management protocol from a management device (not shown), for example,
SNMP (Simple Network Management Protocol), L
DAP (Lightweight Directory Access Protocol),
COPS (Common Open Policy Service) or the like may be used.

Next, the configuration of the virtual router function unit R201 will be described in detail with reference to the example of FIG.

As shown in FIG. 4, the virtual router function unit R201 includes a packet processing unit 401, a packet transfer table 402, and a routing protocol processing unit 4, as shown in FIG.
03, provided with VPN interfaces I401 to I404.

The packet processing unit 401 includes the lower layer processing unit 2
For the VPN packet passed from 01 through one of the VPN interfaces I401 to I404, one of the destination VPN interfaces (VPN interfaces I401 to I404) is determined with reference to the packet transfer table 402, and this is determined. The packet transfer is realized by passing the VPN packet to the lower layer processing unit 201 via the interface.

The contents of the packet transfer table 402 are managed by the routing protocol processing unit 403. The configuration of the packet transfer table 402 is the same as that already described in FIG.

The routing protocol processing unit 403 follows the packet processing unit 40 according to various routing protocols.
It exchanges routing information with other routers via 1 and manages the contents of the packet transfer table 402.

The VPN interfaces I401 to I404 are VP
Interface for sending and receiving N packets, VPN
The packet is transferred to the packet processing unit 401. FIG.
In the example shown in the figure, four VPN interfaces I401 to I404
Is shown. Then, the VPN interface I401 connects the lower layer link D101 shown in FIG.
The interface I402 is a virtual link L102 shown in FIG.
The VPN interface I403 is connected to the virtual link L103 of FIG. 2 and the VPN interface I404 is connected to the virtual link L104 of FIG. 2 via the lower layer processing unit 201.

This correspondence is entered in the column of the transmission interface identifier 703 and the column of the transmission link identifier 704 in the configuration example of the packet transfer table 302 shown in FIG. The present embodiment can be applied to a case where an arbitrary number of VPN interfaces are provided.

Next, the VPN transfer table 202 shown in FIG.
Will be described in detail.

The VPN transfer table 202 is stored in the PE device P101.
When the PE device P101 to P104 receives a packet, it determines from the received link identifier 501 whether or not the PE device processes the packet as the virtual router R101, and how to transfer the packet. Use to determine.

FIG. 5 shows an example of the configuration of the VPN transfer table 202.

As shown in FIG. 5, the VPN transfer table 202 has data items of a reception link identifier 501 and a transfer destination 502. Further, the transfer destination 502 includes a virtual router identifier 503 and a transmission link identifier 504.

When the PE device P101 receives a packet, the received link identifier 501 is used to search for the received link, and a value for identifying the lower layer link D101 or the virtual links L102 to L104 is entered.

The column of the transfer destination 502 is used to determine whether or not the PE device P101 processes a received packet matched by the search for the received link identifier 501 as a virtual router. This column includes a column for the virtual router identifier 503 and a column for the transmission link identifier 504, and a value is entered in either one of them.

When a value is entered in the column of the virtual router identifier 503, it means that the PE device P101 processes the received packet as the virtual router R101.
A value for identifying the virtual router function unit R201 corresponding to the reception link is entered. Then, the virtual router function unit R201 performs VPN packet transfer.

On the other hand, if a value is entered in the column of the transmission link identifier 504, it means that the PE device P101 does not process the received packet as the virtual router R101, and specifies the transmission link corresponding to the reception link. Enter the value to be identified. This transmission link is a lower layer link D1
01 or one of the virtual links L102 to L104. Then, the lower layer processing unit 201 transfers the received packet to the transmission link. At this time, the destination address of the VPN packet is not referred to. Such a transfer method is referred to as “lower layer transfer”.

A data transfer apparatus to which such a data transfer method is applied reads a program recorded on a recording medium such as a magnetic disk, and is realized by a computer whose operation is controlled by the program. Or the Internet to which a plurality of LANs are connected via a public line or a dedicated line. In the case of a LAN, it is composed of a number of subnets via routers as needed. In the case of the Internet, a firewall or the like for connecting to the Internet is appropriately provided, but illustration and detailed description thereof are omitted here.

Next, the operation of the data transfer apparatus to which the data transfer method according to the present embodiment configured as described above is applied will be described.

Here, an operation procedure performed by the PE device when a VPN packet is transmitted from an arbitrary customer network to an arbitrary customer network will be described with reference to a flowchart shown in FIG.

First, as an example of transmitting a VPN packet from a customer network M101 accommodated in a PE device P101 having a virtual router R101 to a customer network accommodated in a PE device having no virtual router, a customer network An operation when a VPN packet is transmitted from M101 to the customer network M102 will be described.

From inside the customer network M101, the customer network M1
When the VPN packet addressed to 02 is transmitted, the VPN packet is received by the CE device C101, and since the destination address is the customer network M102, the packet is transferred to the provider network N101 by the CE device C101. As a result, the VPN packet is received by the PE device P101 via the lower layer link D101 (S1).

The PE device P101 refers to its own VPN transfer table 202 to recognize that the transfer destination of the received VPN packet is the virtual router R101 (S2: virtual router).

[0092] Thus, PE devices P101 functions as a virtual router respect VPN _1, the packet forwarding table 402 within the virtual router function unit R201, a CE device C102 as next destination, the VPN interface
I402 is determined (S3).

Then, the VPN packet is "packet transferred" from the VPN interface I401 to the VPN interface I402 (S4). VPN interface I402
The transmission link connected to the virtual link L102
(S5: virtual link), the VPN packet is transmitted via the virtual link L102 to the PE device P1.
02 (S6).

The operation of the PE device P102 which has received the VPN packet in this manner will be described returning to step S1 in the flowchart of FIG. That is, when a VPN packet is received by the PE device P102 through the virtual link L102 (S1), the PE device P102
The VPN transfer table 202 held in the E device P102 is referred to, and it is recognized that the transfer destination of the VPN packet is the transmission link (lower layer link D102) (S
2: transmission link).

[0095] Thus, PE devices P102 may not function as a virtual router respect VPN _1, VPN packet is "lower layer transfer" from the virtual link L102 to the lower layer link D102 (S7).

In this case, since the type of the transmission link is the lower layer link (S5: lower layer link), the VP
The N packet is transmitted to the CE device C102 via the lower layer link D102 (S8).

Thus, the VPN packet is transmitted to the CE device.
C102, the destination address of which is addressed to the customer network M102.
02, the packet is received inside the customer network M102, and the packet transfer is completed.

Next, the virtual router R101 is sent from the customer network accommodated in the PE device having no virtual router.
To customer network M101 accommodated in PE device P101 having
As an example of transmitting a PN packet, the customer network M1
The operation when a VPN packet is transmitted from 02 to the customer network M101 will be described.

From inside the customer network M102, the customer network M1
When the VPN packet addressed to 01 is transmitted, the VPN packet is received by the CE device C102, and since the destination address is the customer network M101, the packet is transferred to the provider network N101 by the CE device C102. As a result, the VPN packet is received by the PE device P102 via the lower layer link D102 (S1).

The PE device P102 refers to its own VPN transfer table 202 to recognize that the transfer destination of the received VPN packet is the transmission link (virtual link L102) (S2: transmission link).

[0102] Thus, PE devices P102 may not function as a virtual router respect VPN _1, VPN packet is "lower layer transfer" from the lower layer link D102 to a virtual link L102 (S7).

In this case, since the type of the transmission link is a virtual link (S5: virtual link), the VP
The N packet is transmitted to the PE device P101 via the virtual link L102 (S6).

The operation of the PE device P101 that has received the VPN packet in this manner will be described returning to step S1 in the flowchart of FIG. That is, when a VPN packet is received by the PE device P101 via the virtual link L102 (S1), the PE device P101 outputs
The VPN transfer table 202 held in the E device P101 is referred to, and it is recognized that the transfer destination of the VPN packet is the virtual router R101 (S2: virtual router).

[0104] Thus, PE devices P101 functions as a virtual router respect VPN _1, the packet forwarding table 402 within the virtual router function unit R201, a CE device C101 as next destination, the VPN interface
I401 is required (S3).

Then, the VPN packet is "packet transferred" from the VPN interface I402 to the VPN interface I401 (S4). Since the transmission link connected to the VPN interface I401 is the lower layer link D101 (S5: lower layer link), the VPN packet is transmitted to the CE device C101 via the lower layer link D101 (S6).

Thus, the VPN packet is transmitted to the CE device.
C101, the destination address of which is addressed to the customer network M101.
The packet is transferred to 01, received inside the customer network M101, and the packet transfer is completed.

Next, P without a virtual router
As an example of transmitting a VPN packet from the customer network accommodated in the E device to the customer network accommodated in the PE device having no virtual router, an operation in the case of transmitting a VPN packet from the customer network M102 to the customer network M103 Will be described.

The customer network M1 is sent from inside the customer network M102.
When the VPN packet addressed to 03 is transmitted, the VPN packet is received by the CE device C102, and since the destination address is addressed to the customer network M103, the packet is transferred to the provider network N101 by the CE device C102. As a result, the VPN packet is received by the PE device P102 via the lower layer link D102 (S1).

The PE device P102 refers to its own VPN transfer table 202 to recognize that the transfer destination of the received VPN packet is the transmission link (virtual link L102) (S2: virtual link).

[0110] Thus, PE devices P102 may not function as a virtual router respect VPN _1, VPN packet is "lower layer transfer" from the lower layer link D102 to a virtual link L102 (S7).

In this case, since the type of the transmission link is a virtual link (S5: virtual link), the VP
The N packet is transmitted to the PE device P101 via the virtual link L102 (S6).

The operation of the PE device P101 that has received the VPN packet in this way will be described returning to step S1 in the flowchart of FIG. That is, when a VPN packet is received by the PE device P101 via the virtual link L102 (S1), the PE device P101 outputs
The VPN transfer table 202 held in the E device P101 is referred to, and it is recognized that the transfer destination of the VPN packet is the virtual router R101 (S2: virtual router).

[0113] Thus, PE devices P101 functions as a virtual router respect VPN _1, the packet forwarding table 402 within the virtual router function unit R201, a CE device C103 as next destination, the VPN interface
I403 is determined (S3).

Then, the VPN packet is "packet transferred" from the VPN interface I402 to the VPN interface I403 (S4). Since the transmission link connected to the VPN interface I403 is the virtual link L103 (S5: virtual link), the VPN packet is transmitted to the PE device P103 via the virtual link L103 (S6).

The operation of the PE device P103 that has received the VPN packet in this manner will also be described by returning to step S1 in the flowchart of FIG. That is, the VPN packet is transmitted to the PE device P103 via the virtual link L103.
(S1), the VPN transfer table held in the PE device P103 by the PE device P103.
Reference is made to 202, and it is recognized that the transfer destination of this VPN packet is the transmission link (lower layer link D103) (S2: transmission link).

[0116] Thus, PE devices P103 may not function as a virtual router respect VPN _1, VPN packet is "lower layer transfer" from the virtual link L103 to the lower layer link D103 (S7).

In this case, since the type of the transmission link is the lower layer link (S5: lower layer link), the VP
The N packet is transmitted to the CE device C103 via the lower layer link D103 (S8).

Thus, the VPN packet is transmitted to the CE device.
C103, the destination address of which is addressed to the customer network M103.
03, the packet is transferred to the customer network M103, and the packet transfer is completed.

As described above, in the data transfer apparatus to which the data transfer method according to the present embodiment is applied, the virtual router R101 for a specific VPN is connected to one of the provider networks N101 by the above operation. PE equipment
By arranging at P101, the number of routing protocol sessions for VPN can be suppressed to the order of the number of CE devices C101 to C104.

The virtual link L1 for the VPN
The number of 02 to L104 can also be suppressed to the order of the number of CE devices C101 to C104.

That is, it is possible to reduce the functional load and the processing load of the PE devices P102 to P104. Further, the resource consumption of the provider network N101 can be reduced, and as a result, control efficiency can be improved.

In the above embodiment, the term “terminal” refers to a CE device C 101 to C 104 or a CE device
It corresponds to the customer networks M101 to M104 including C101 to C104. The data receiving unit, the data transfer unit, the data transmitting unit, the connecting unit, and the data transmitting / receiving unit described in the claims all correspond to the PE devices P101 to P104 in the above embodiment.
The data allocating means described in claims corresponds to the virtual router R101 in the above embodiment.

The apparatus described in the above embodiment can be realized by causing a computer to read a program stored in a recording medium.

Here, as the recording medium in the present invention,
Magnetic disk, floppy (registered trademark) disk, hard disk, optical disk (CD-ROM, DVD, etc.),
As long as the program can be recorded and a computer-readable recording medium such as a magneto-optical disk (MO or the like) or a semiconductor memory can be used, the recording format thereof may be any.

Also, an OS (Operating System) running on the computer based on the instructions of the program installed in the computer from the recording medium,
MW for database management software, network software, etc.
(Middleware) or the like may execute a part of each process for implementing the present embodiment.

Further, the recording medium in the present invention is not limited to a medium independent of a computer, but also includes a recording medium in which a program transmitted via a LAN, the Internet or the like is downloaded and recorded or temporarily recorded.

Further, the number of recording media is not limited to one, and the case where the processing in the present embodiment is executed from a plurality of media is also included in the recording medium of the present invention, and the medium may have any configuration. .

The computer according to the present invention executes each processing in the present embodiment based on a program recorded on a recording medium. An apparatus such as a personal computer and a plurality of apparatuses are connected to a network. Any configuration such as a connected system may be used.

Further, the computer in the present invention is:
It is not limited to a personal computer, but also includes a processing device, a microcomputer, and the like included in an information processing device, and generically refers to a device and a device capable of implementing the functions of the present invention by a program.

The present invention is not limited to the above embodiment, but can be implemented in the following manner.

That is, in the present embodiment, a case has been described in which four PE devices P101 to P104 are provided in the provider network N101, but this is an example, and there is a case where there are other numbers of PE devices. Is also applicable.

Further, in the present embodiment, the case has been described where the virtual router R101 for a certain VPN is provided in one PE device P101 of the provider network N101. However, this is an example, and this is an example. Virtual router may be provided in a plurality of PE devices. When the number of PE devices provided in the provider network N101 is large, the load on the virtual router is large.
By providing a virtual router in the E device, it is possible to reduce the load imposed on one virtual router.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIG.

FIG. 8 is a block diagram showing an example of a data transfer apparatus to which the data transfer method according to the second embodiment is applied. The same parts as those in FIG. Here, only the different parts will be described.

That is, data transfer according to the present embodiment
The data transfer device to which the method is applied includes PE devices P101 to P104.
Is connected to multiple CE devices via lower layer links.
Connected. The PE device P101 is a lower layer link D101.
_a, D101_bCE device C101 via_a, C101_bConnect with
The PE device P102 is connected to the lower layer link D102._a, D102 _b
CE device C102 via_a, C102_bConnected to the PE
The device P103 is a lower layer link D103_a, D103_bVia C
E device C103_a, C103_bAnd the PE device P104
Lower layer link D104_a, D104_bCE device C104 via
_a, C104_bAnd each is connected.

Further, the provider network N101 has two VPNs.
That is handling the VPN _a and VPN _b. CE
Customer network M101 with device C101 _{a a,} CE device C102 _a
Customer network M1 having a customer network M103 _a, CE device C 104 _a having a customer network M102 _a, CE device C103 _a having
04 _a is a customer network belonging to the VPN _a. CE device
C101 customer network M101 with _{b b,} CE device C102 customer network M102 _b with _b, CE device C103 customer network M103 with _{b b,} CE device C104 customer network M104 has a _{b b}
Is a customer network belonging to VPN _b .

Furthermore, in addition to the PE device P101, the PE device P104
Also has a virtual router R104. This virtual router R104 is a virtual router that controls VPNb, and is a virtual router provided in the PE device P101.
R101 is a virtual router to control the VPN _a.

A PE device P1 having a virtual router R104
From 04, new virtual links L105 to L107 are provided, and these virtual links L105, L106, L107 allow the PE devices P101, P102, P1 to be transmitted from the virtual router R104.
It is possible to transfer packet data to 03, or vice versa, and to receive packet data transmitted from the PE devices P101, P102, P103 to the PE device P104.

Next, the operation of the data transfer apparatus to which the data transfer method according to the present embodiment configured as described above is applied will be described.

That is, in the present embodiment, as shown in FIG. 8, the provider network N101 has a plurality of VPNs (in this case,
PN _a and VPN _b ).
The virtual router R101 for VPN _a to PE equipment P101,
A virtual router R104 for VPN _{b is} provided in each of the PE devices P104.

[0141] Thus, the packet forwarding table 402 PE device P101 to be managed may just relate VPN _a, CE device should exchange routing information also CE device _{C101 a, C102 a, C103 a} , C104 a Just good.

On the other hand, the packet transfer table to be managed by the PE device P104 only needs to be related to VPN _b , and the CE device to exchange routing information is also the CE device C1
_{01 b, C102 b, C103 b} , C104 b may only.

That is, V handled by the provider network N101
Even though the number of PNs has increased from 1 in the first embodiment to 2, the number of packet transfer tables to be managed by the PE device P101 and the routing protocol to be processed are the same as those in the first embodiment. It has not increased compared to the case of the form.

As described above, in the present embodiment, even if the number of VPNs handled by the provider network N101 increases, the virtual router R104 for managing the increased VPN, VPNb, is already set to the virtual router R101. A new VPN can be managed without causing an increase in the load on the PE device P101 by providing the PE device P104 that is different from the PE device P101 having the same.

Note that the virtual link L10 in FIG.
4, L105 are terminated by the same provider interface in the same PE devices P101 and P104, respectively. For example, when such virtual links are realized by LSPs, they need not necessarily be realized by separate LSPs. Specifically, one LSP is set between the PE device P101 and the PE device P104, and a hierarchical label is used in the LSP,
Different labels may correspond to the respective virtual links in lower layers.

As described above, by multiplexing a plurality of virtual links, the provider network N1 realizing the VPN is realized.
At 01, resources for realizing a virtual link such as an LSP label can be saved.

As described above, in the data transfer apparatus to which the data transfer method according to the present embodiment is applied, the VP handled by the provider
Even if there are a plurality of N, by providing a virtual router for managing each VPN in a separate PE device, the same operation as in the first embodiment can be performed without increasing the load on the PE device. The effect can be achieved.

Although the preferred embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to such configurations. Within the scope of the technical idea described in the claims, those skilled in the art can come up with various modified examples and modified examples, and these modified examples and modified examples are also within the technical scope of the present invention. It is understood that it belongs to.

[0149]

As described above, according to the present invention,
By integrating the functions of the virtual routers conventionally provided in each PE device of the provider network by the number of VPNs, the number of VPNs can be provided in the provider network by integrating the functions.

As described above, a data transfer method and a data transfer device capable of distributing the functional load and processing load of a PE device and reducing the control load and resource consumption in a provider network, and a recording medium on which a program is recorded are provided. Can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration example of a data transfer device to which a data transfer method according to a first embodiment is applied.

FIG. 2 is a block diagram showing a configuration example of a PE device provided with a virtual router;

FIG. 3 is a block diagram showing a configuration example of a provider router function unit.

FIG. 4 is a block diagram showing a configuration example of a virtual router function unit;

FIG. 5 is a schematic diagram showing a configuration example of a VPN transfer table.

FIG. 6 is a schematic diagram showing a configuration example of a packet transfer table.

FIG. 7 is a flowchart showing a data transfer procedure performed in the PE device.

FIG. 8 is a block diagram showing an overall configuration example of a data transfer device to which a data transfer method according to a second embodiment is applied;

FIG. 9 is an overall configuration diagram showing an example of a data transfer device of this type according to the related art.

FIG. 10 is an overall configuration diagram showing another example of this type of conventional data transfer apparatus.

[Explanation of symbols]

C101 to C104: CE device C201: Customer interface D1
01 to D104 Lower layer links I401 to I404 VPN interfaces L102 to L107 Virtual links M101 to M104 Customer network N101 Provider networks P101 to P104 PE device P201
... P203: Provider interfaces R101 to R104: Virtual router R201: Virtual router function unit 201: Lower layer processing unit 202: VPN transfer table 203 ... Provider router function unit 301: Packet processing unit 302 ... Packet transfer table 303: Routing protocol processing unit 304 virtual link control unit 305 VPN topology management unit 401 packet processing unit 402 packet transfer table 403 routing protocol processing unit 501 received link identifier 502 transfer destination
503: virtual router identifier 504: transmission link identifier 70
1 destination prefix 702 next stage information 703 transmission interface identifier 704 transmission link identifier

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kenichi Nagami 1 Toshiba-cho, Fuchu-shi, Tokyo F-term in the Fuchu Plant of Toshiba Corporation 5K030 GA03 GA04 HA08 HC14 HD03 HD06 KA05 LB05 5K033 AA03 AA09 CC02 DA05 DB19 5K034 AA07 AA10 BB06 KK21

Claims (9)

[Claims] At least one terminal belonging to a certain network group is connected, and a plurality of data receiving means for receiving data transmitted from the terminal together with destination information of the data; and a plurality of data receiving means for receiving data transmitted by the data receiving means. Data transfer means for transferring the transferred data based on the network group to which the source terminal belongs, and a transfer destination of the data transferred from the data transfer means, provided for each network group, and Data allocating means for allocating and transmitting the transferred data based on the transmission destination information of the data, and at least one of the transmission destinations of the data allocated and transmitted by the data allocating means and belonging to a certain network group.
The two terminals connect and transmit the allocated and transmitted data,
A data transfer device comprising: a plurality of data transmitting means for transmitting to a terminal belonging to the same network group as a network group to which the source terminal belongs, among the connected terminals. 2. A plurality of data receiving means to which at least one terminal belonging to a certain network group is connected and which receives data transmitted from the terminal together with destination information of the data, and a plurality of data receiving means which are received by the data receiving means. Data transfer means for transferring the transferred data based on the network group to which the source terminal belongs, and a transfer destination of the data transferred from the data transfer means, provided for each network group, and Data allocating means for allocating and transmitting the transferred data based on the transmission destination information of the data, and at least one of the transmission destinations of the data allocated and transmitted by the data allocating means and belonging to a certain network group.
The two terminals connect and transmit the allocated and transmitted data,
A data transfer device comprising: a plurality of data transmitting means for transmitting to the terminal based on the destination information among the connected terminals. 3. A plurality of connection means to which at least one terminal belonging to a certain network group is connected, and data provided in each of the connection means and receiving data transmitted from the terminal together with destination information of the data. Receiving means, data transfer means provided in each of the connection means, for transferring data received by the data reception means of the same connection means based on the network group to which the source terminal belongs; Is provided in any one of the connection means, and is a transfer destination of the data transferred from the data transfer means, based on the transmission destination information of the transferred data Data allocating means for allocating and transmitting;
A transmission destination of the data allocated and transmitted by the data allocating unit, provided in each of the connection units, and the allocated and transmitted data is transmitted to the transmission destination information among the terminals to which the own connection unit is connected. And a data transmission means for transmitting the data to a terminal based on the data. 4. The data transfer device according to claim 3, wherein said data allocating means is connected to each of said plurality of connection means for each of said network groups and less than all of said connection means. A data transfer device, wherein the data transfer device is provided in a means. 5. A terminal belonging to the same network group as its own in data including information of a destination terminal, which is received by a plurality of data transmitting / receiving means connected to at least one terminal belonging to a certain network group. When there is data transmitted from the data receiving unit, the data is received from the data transmitting / receiving unit, and the data is transferred to the data transmitting / receiving unit to which the destination terminal is connected, based on the information of the destination terminal. Causing the data transmitting / receiving means to output the data to the destination terminal;
A data transfer device comprising a data allocating means provided for each of the network groups. 6. A plurality of data receiving means for connecting to at least one terminal belonging to a certain network group and receiving data transmitted from the terminal together with destination information of the data, and a plurality of data receiving means for receiving data transmitted by the data receiving means. Data transfer means for transferring the transferred data based on the network group to which the source terminal belongs and the destination information, and a transfer destination of the data transferred from the data transfer means, and belonging to a certain network group. A plurality of data to which at least one terminal is connected and which transmits data transferred from the data transfer means to terminals belonging to the same network group as the network group to which the source terminal belongs among the connected terminals; A data transfer device comprising: a transmission unit. 7. At least one terminal belonging to a certain network group connects, receives data including transmission destination information transmitted from the terminal by a data receiving unit, and receives data received by each of the data receiving units. And transmitting the transmitted data based on the destination information of the transmitted data, and allocating and transmitting the transmitted data by data allocating means provided for each of the network groups. The data allocated and transmitted by the data allocating means is transmitted to a terminal to which the terminal is connected via one of a plurality of data transmitting means connected to at least one terminal belonging to a certain network group. Wherein the data is transmitted to a terminal based on the destination information. Transfer method. 8. At least one terminal belonging to a certain network group connects, receives data transmitted from the terminal together with destination information of the data by a plurality of data receiving means, and receives the data by the data receiving means. Data based on the network group to which the source terminal belongs and the destination information, and transfers the transferred data to a plurality of data transmission units connected by at least one terminal belonging to a certain network group. A data transfer method, characterized in that data is transmitted to a terminal belonging to the same network group as a network group to which the source terminal belongs via any one of them. 9. A recording medium recording a program for controlling a data transfer device for transferring data from a source terminal to a destination terminal, wherein at least one terminal belonging to a certain network group is connected to the computer. If there is data transmitted from a terminal belonging to the same network group as the network group specified in advance among the data including the information of the destination terminal received by the plurality of data transmitting / receiving means, Causing the data transmitting / receiving means to acquire the data, transmitting the data to the data transmitting / receiving means connected to the destination terminal based on information of the destination terminal of the data, and further transmitting the data from the data transmitting / receiving means. And a computer-readable recording medium storing a program for causing the destination terminal to output body.