JP2001045064A - Ip packet transfer method, device therefor and storage medium storing ip packet transfer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the transfer capability of a packet repeater by encapsulating a plurality of packets distributed to a user network accommodation device passed in the case of transfer into a form of AAL type 5, separating them into single packets respectively and transferring them to a user network. SOLUTION: In the case that an IP packet transfer network transfers a packet received from a user network to other user network according to its header information, all user network accommodated positions through which the packet passes are obtained. Thus, in the case of encapsulating a plurality of distributed packets, a plurality of the distributed packets is encapsulated into packets of AAL type 5, a new cell including the header information of a connectionless transfer protocol generated on the basis of the header information of the packet is added to a part before the encapsulated cells. The band of the cell including the header information is reduced and the band of the IP packet transfer network can efficiently be utilized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IP packet transfer method and apparatus and a storage medium storing an IP packet transfer program, and more particularly to a connectionless packet from a user network to a user network through an IP packet transfer network such as the Internet. The present invention relates to an IP packet transfer method and apparatus for improving the transfer capability of an IP packet transfer network when performing packet transfer and performing packet transfer processing suitable for a broadband backbone, and a storage medium storing an IP packet transfer program.

[0002]

2. Description of the Related Art A conventional IP packet transfer method will be described below. A plurality of user networks are accommodated through a plurality of ports, and I
A user network accommodating device for encapsulating a P packet into a connectionless transfer protocol different from IP for transfer and a packet relay device for transferring using the connectionless transfer protocol are connected by a link, and a frame is fixed. I divided into long cells and transferred
There is a P packet forwarding network.

[0003] In a user network accommodating apparatus for transferring a packet from a user network to an IP packet transfer network, a packet received from the user network is transmitted according to ITU-T Recommendation I.T. Encapsulated in AAL type 5 which is a protocol specified in 363,5,
The encapsulated one is converted into a cell, and one new cell including the header information of the connectionless transfer protocol generated based on the header information of the packet is added before the cellized one, so that the new cell becomes the first cell. , Followed by encapsulation into a packet of the connectionless transfer protocol having a format in which one packet of the AAL type 5 format is formed into a cell, and the packet is transferred to the packet relay device.

[0004] The packet relay apparatus receives a packet of the connectionless transfer protocol, and transfers the packet to the next packet relay apparatus or user network accommodating apparatus based on header information included in the first cell. In a user network accommodating device for transferring a packet from a packet relay device to a user network, an AAL type 5 format packet is removed by removing cells containing header information of the connectionless transfer protocol from the received connectionless transfer protocol packet. Is decapsulated into a cell, and the packet is transferred to the user network.

[0005]

However, in the conventional apparatus, when performing encapsulation, a new cell including header information of the connectionless transfer protocol is added to one AAL type 5 format packetized cell. When the encapsulated packet is transferred by the packet relay device in the packet transfer network, it is necessary to perform protocol processing for each packet transfer every time. There is a problem that causes a decrease in

In addition, since one cell is added to one AAL type 5 packet which is made into a cell, there is a problem in that the bandwidth of the packet transfer network is wasted by the added cell. SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and improves the transfer capability of a packet relay device in an IP packet transfer network, and efficiently utilizes the bandwidth of the IP packet transfer network. IP packet transfer method and apparatus capable of realizing network broadband and IP
An object is to provide a storage medium storing a packet transfer program.

[0007]

FIG. 1 is a diagram for explaining the principle of the present invention. The present invention (claim 1) provides a user network that accommodates a plurality of user networks via a plurality of ports and encapsulates IP packets transferred from the user network into a connectionless transfer protocol different from IP to transfer the packets. An IP packet transfer method in an IP packet transfer network for connecting an accommodating device and a packet relay device for performing transfer using the connectionless transfer protocol in a network by a communication link and dividing a frame into fixed-length cells. In a user network accommodating apparatus for transferring a packet from a user network to an IP packet transfer network, a packet received from the user network is transferred from the IP packet transfer network to the user network based on header information. Determined at least one user network accommodation device through which are transferred, distributed for each user network accommodation device (Step 1), a plurality of packets sorted, ITU-T Recommendation I. Encapsulation in AAL type 5 which is a protocol specified in 363.5, and adding a new cell including header information of a connectionless transfer protocol generated based on header information of the packet before cellization. The new cell is encapsulated into a connectionless transfer protocol packet having a format in which the new cell is located at the head and a plurality of AAL type 5 format packets are arranged in a cell behind the new cell (step 2). The packetized packet is transferred to the packet relay device (step 3), and the packet relay device receives the packet of the connectionless transfer protocol, and converts the packet of the connectionless transfer protocol to the next packet according to the header information included in the first cell. Relay device or user network accommodation In the user network accommodation device that has received the connectionless transfer protocol packet from the packet relay device (step 4), and removes the cell containing the connectionless transfer protocol header information from the connectionless transfer protocol packet. A
The AAL type 5 format packet is decapsulated into a plurality of cellized packets (step 5).
Each type 5 packet is separated into individual packets (step 6) and transferred to the user network (step 7).

FIG. 2 is a diagram showing the principle of the present invention. According to the present invention (claim 2), a plurality of user networks 10 are accommodated through a plurality of ports, and an IP packet transferred from the user network 10 is encapsulated in a connectionless transfer protocol different from IP and transferred. An IP packet in an IP packet transfer network that connects a user network accommodating device 20 and a packet relay device 50 that performs transfer using the connectionless transfer protocol in a network through a communication link and divides a frame into fixed-length cells. The transfer device, which transfers a packet from the user network 10 to the IP packet transfer network, converts the packet received from the user network 10 from the IP packet transfer network by using the header information. Determined at least one user network accommodation device through which is transferred to the user network, the distribution for each user network accommodation apparatus, a plurality of packets sorted, ITU-T Recommendation I. AAL, a protocol specified in 363.5
By adding a new cell including the header information of the connectionless transfer protocol generated based on the header information of the packet before encapsulating it in type 5 and forming the cell, the new cell is positioned at the top, Encapsulating means 21 for encapsulating the packet into a connectionless transfer protocol packet having a format in which a plurality of AAL type 5 format packets are arranged behind the packet, and transferring the encapsulated packet to a packet relay device. The first transfer means 22 and the packet relay device 5
When a packet of the connectionless transfer protocol is received from 0, a plurality of AAL type 5 format packets are arranged in a cell by removing cells including header information of the connectionless transfer protocol from the connectionless transfer protocol packet. A decapsulation unit 23 that decapsulates the packet into AAL type 5 packets and separates each packet into a single packet, and a second transfer unit 24 that transfers the separated packet to the user network 10. Packet relay device 50
Means for receiving a packet of the connectionless transfer protocol from the user network accommodating apparatus 20, and transferring the packet of the connectionless transfer protocol to the next packet relay apparatus or the user network accommodating apparatus according to the header information contained in the first cell. 51.

The present invention (claim 3) accommodates a plurality of user networks via a plurality of ports, encapsulates an IP packet transferred from the user network into a connectionless transfer protocol different from IP, and transfers the packet. User network accommodating apparatus and a packet relay apparatus for performing transfer using the connectionless transfer protocol are connected in a network form by a communication link, and the user network in an IP packet transfer network for dividing a frame into fixed-length cells A storage medium storing an IP packet transfer program mounted on an accommodating device, wherein at least a packet received from the user network is passed when the packet is transferred from the IP packet transfer network to the user network by header information. One of the determined user network accommodation apparatus, distributing to each of the user network accommodation apparatus, a plurality of packets sorted, ITU-T Recommendation I. AAL, a protocol specified in 363.5
By adding a new cell including the header information of the connectionless transfer protocol generated based on the header information of the packet before encapsulating it in type 5 and forming the cell, the new cell is positioned at the top, An encapsulation process for encapsulating the packet into a connectionless transfer protocol packet having a format in which a plurality of AAL type 5 format packets are arranged behind the cell, and transferring the encapsulated packet to the packet relay device. The first transfer process, and upon receiving a packet of the connectionless transfer protocol from the packet relay device, removes a cell containing header information of the connectionless transfer protocol from the packet of the connectionless transfer protocol, thereby forming an AAL type 5 format. Packetize cells What performs decapsulation to those aligned plurality, AAL type 5 and decapsulation process of separating the packet format to each single packet, the second to be transferred the separated packet to the user network
And a transfer process.

As described above, according to the present invention, in a user network accommodating apparatus, when a packet received from a user network is transferred from an IP packet transfer network to a user network based on header information, all user network accommodating apparatuses passing through the network are transferred. When the packet is divided into a plurality of packets and encapsulation is performed, the divided packets are encapsulated into AAL type 5 and generated based on the header information of the packet before the cellized one. Encapsulation is performed by adding a new cell including header information of the connectionless transfer protocol.

When performing decapsulation, a plurality of AAL type 5 format packets are removed from a packet received from a packet relay device of an IP packet transfer network by removing cells containing header information of a connectionless transfer protocol. The packet is decapsulated into a plurality of cells, and the AAL type 5 format packets are separated into individual packets and transferred to the user network.

As described above, by encapsulating a plurality of AAL type 5 format packets into cells by adding a new cell including header information of one connectionless transfer protocol, one AAL is obtained.
The number of packets per header information is increased as compared with the conventional method in which only one new cell is added to the packetized type 5 packet, and the packet relay device in the IP packet transfer network transfers the packet. It becomes possible to reduce the frequency of protocol processing per packet at the time of transfer.

Similarly, since the number of packets per cell including the header information increases, the bandwidth of the cell including the header information can be reduced, and the bandwidth of the IP packet transfer network can be used efficiently. As a result, it is possible to realize a wider band of the IP packet transfer network.

[0014]

FIG. 3 shows the configuration of an IP packet transfer apparatus according to the present invention. The IP packet transfer apparatus shown in FIG. 1 is configured by connecting user network accommodation apparatuses 31 to 36 and packet relay apparatuses 41 and 42 by a link. The user network accommodation devices 31 to 36 accommodate the user networks 201 to 218 via a plurality of ports, and encapsulate IP packets transferred from the user networks 201 to 218 into a connectionless transfer protocol different from IP and transfer them. I do.

The packet relay devices 41 and 42 perform transfer using the connectionless transfer protocol. FIG. 4 shows the configuration of the user network accommodation device of the present invention. The user network accommodating device 31 includes a user network input interface (IF) unit 3111 to which packets are input from the user networks 201 to 203.
3113, a packet distribution unit 312 that determines a buffer to which a packet is input, a plurality of buffers 3131 to 1137 that hold the input packet until it is read out,
An encapsulation unit 314 for continuously reading and encapsulating a plurality of packets stored in the buffers 3131 to 1137, and an IP packet transfer network output interface (IF) unit 315 for outputting the encapsulated packets to an IP packet transfer network. IP packet transfer network input interface (IF) unit 31 to which a packet is input from the IP packet transfer network
6. Decapsulation unit 31 for decapsulating a packet
7. User network output interface (I) for outputting the decapsulated packet to the user network
F) Units 3181 to 1183.

Although FIG. 4 shows only the user network accommodating apparatus 31, the other user network accommodating apparatuses 32-35 have the same configuration. The packet sorting unit 312 obtains, from the header information of the packet, whether the packet passes through any of the user network accommodation devices 31 to 36 when the packet is transferred from the IP packet transfer network to the user network. To multiple buffers 31
Distribute to 31 to 137.

FIG. 5 shows the configuration of the encapsulation unit of the user network accommodating device of the present invention. Encapsulation unit 314
Is a header cell generation unit 3141 and a header cell addition unit 3
142, which performs processing for encapsulating an IP packet transferred from the user network into a packet of a connectionless transfer protocol used in the IP packet transfer network.

The header cell generator 3141 generates a cell including header information of the connection transfer protocol from the header information of the packets stored in each of the buffers 3131 to 137. The header cell adding unit 3142 continuously reads a plurality of packets stored in each of the buffers 3131 to 1137, encapsulates the plurality of packets read from the header cells generated by the header cell generating unit 3141 into AAL type 5, and converts the plurality of packets into the AAL type 5. To be added.

Thus, the IP packet can be encapsulated into a connectionless transfer protocol packet. FIG. 6 shows the configuration of the decapsulation unit of the user network accommodation device of the present invention. Decapsulation unit 317
Are the header cell removing unit 3171 and the packet separating unit 317
2, which performs a process of decapsulating a packet of the connection transfer protocol into an IP packet.

The header cell removing unit 3171 removes a cell including the header information at the head from the packet of the connectionless transfer protocol. As a result, a packet of the connectionless transfer protocol has a form in which only a plurality of AAL type 5 format packets are arranged in a cell. The packet separating unit 3172 separates a plurality of packets of the AAL type 5 format that are arranged side by side into individual packets. Thereby, it is possible to decapsulate the connectionless transfer protocol packet into the IP packet.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. Hereinafter, the operation will be described based on the configuration of the IP packet transfer device shown in FIGS. In the following example, the user network accommodation device 31, the packet relay device 41
This will be described with reference to FIG.

FIG. 7 is a sequence chart of an IP packet transfer operation according to one embodiment of the present invention. Step 10
1) The user network input IF unit 3111 of the user network accommodation device 31 receives a packet from the user network 201, the user network input IF unit 3112 receives a packet from the user network 202, and
It is assumed that a packet has been received from the user network 203 in 113.

Step 102) Packet distribution unit 31
In 2, determine at least one user network accommodation device to be transferred. Step 103) The packet distribution unit 312 distributes packets to be transferred to the user network accommodation device, and stores the packets in the buffers 3131 to 31.
37. Step 104) Encapsulation unit 31
4 in the header cell generation unit 3141
A new cell including header information of the connectionless transfer protocol is generated based on the header information of the plurality of packets allocated in step 3, and the header cell adding unit 3142 converts the plurality of packets allocated in step 103 into cells. Connectionless transfer in a format (described later with reference to FIG. 8) in which the new cell is added before, the new cell is positioned at the top, and a plurality of AAL type 5 format packets are arranged in a cell. Encapsulate in protocol packets.

Step 105) The IP packet transfer network output IF unit 315 transfers the packet to the packet relay device 41. Step 106) Packet relay device 41
Receives the packet of the connectionless transfer protocol, relays the packet to the packet relay device 42 based on the header information included in the first cell, and the packet relay device 42 receives the packet of the connectionless transfer protocol, The packet is transferred to the user network accommodating device according to the header information included in the cell.

Step 107) Upon receiving the packet, the user network accommodating apparatus receives the packet of the connectionless transfer protocol at the IP packet transfer network input IF section, and in the header cell removing section of the decapsulation section, the header information of the connectionless transfer protocol. By removing the cell including the AAL type 5, the packet of the AAL type 5 format is decapsulated into a plurality of cellized packets.

Step 108) In the packet separation unit of the decapsulation unit of the user network accommodation device, A
Each of the AL type 5 format packets is separated into individual packets. Step 109) Transfer the separated single packets from the user network output IF unit of the user network accommodating device to the user network.

Next, the connectionless transfer protocol format encapsulated in step 104 will be described. FIG. 8 shows a connectionless transfer protocol format according to an embodiment of the present invention.
A cell 6 including header information of the connectionless transfer protocol is located at the head of the IP packet transfer network frame 5, and thereafter, an AAL5 format user network frame 7, which is a plurality of AAL type 5 format packetized cells.
1 to 73 are arranged.

The additional cell 6 comprises an ATM cell header 61 and a payload, and the payload is the LLC of the additional cell.
/ SNAP header 62 and a connectionless transfer protocol header 63 are included. The first cell of the AAL type 5 format frame includes a user network frame LLC / SNAP header 711 and an IP header 712. The last cell is the AAL type 5 trailer 73 of the user network frame.
3 inclusive.

In the above embodiment, the description has been given based on the configuration of the user network accommodating apparatus of FIG. 4. However, the packet distribution unit, the encapsulating unit, and the decapsulating unit of the user network accommodating apparatus are constructed as a program, Disk devices connected to computers used as network accommodation devices, floppy disks,
The present invention can be easily realized by storing the program in a portable storage medium such as a CD-ROM and installing it when implementing the present invention.

The present invention is not limited to the above embodiment, but can be variously modified and applied within the scope of the claims.

[0031]

As described above, according to the present invention, one or a plurality of user network accommodation devices to which a packet is to be transferred are determined, distributed to each packet, and the distributed packet is encapsulated. By performing the transfer, the bandwidth of the IP packet transfer network can be widened, so that the cost performance of the IP packet transfer network can be improved and the user cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the principle of the present invention.

FIG. 2 is a principle configuration diagram of the present invention.

FIG. 3 is a configuration diagram of an IP packet transfer device of the present invention.

FIG. 4 is a configuration diagram of a user network accommodation device of the present invention.

FIG. 5 is a configuration diagram of an encapsulation unit of the user network accommodation device of the present invention.

FIG. 6 is a configuration diagram of a decapsulation unit of the user network accommodation device of the present invention.

FIG. 7 is a sequence chart of an IP packet transfer operation according to one embodiment of the present invention.

FIG. 8 is a connectionless transfer protocol format according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 IP packet transfer apparatus 5 IP packet transfer network frame 6 Additional cell 10 User network 20 User network accommodating apparatus 21 Encapsulation means 22 First transfer means 23 Decapsulation means 24 Second transfer means 31-36 User network accommodation apparatus 41 , 42 packet relay device 50 packet relay device 51 relay means 61 ATM cell header 62 additional cell header 63 IP packet transfer network frame header 71 to 73 user network frame 201 to 218 user network 312 packet distribution unit 314 encapsulation unit 315 IP packet transfer network output Interface section 316 IP packet transfer network input interface section 317 Decapsulation section 711 User network frame header 712 User network frame header D 733 User network frame AAL5 trailer 3111 to 3113 User network input interface unit 3141 Header cell generation unit 3142 Header cell addition unit 3171 Header cell removal unit 3172 Packet separation unit 3181 to 1183 User network output interface unit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroyuki Hara 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term (reference) in Nippon Telegraph and Telephone Corporation 5K030 GA03 HB19 HC01 JA01 JA06 KA02 LB18 LE06 5K033 AA01 CB08 CC01 DA05 DB18 9A001 CC06

Claims (3)

[Claims] A user network accommodating device that accommodates a plurality of user networks via a plurality of ports and encapsulates and transfers IP packets transferred from the user networks into a connectionless transfer protocol different from IP; An IP packet transfer method in an IP packet transfer network for connecting a packet relay device performing transfer using the connectionless transfer protocol in a network form by a communication link and dividing a frame into cells of a fixed length. In the user network accommodating apparatus for transferring a packet to an IP packet transfer network, a packet received from the user network is transferred from the IP packet transfer network to the user network according to header information. Determined at least one user network accommodation device through which are transferred, distributed for each user network accommodation apparatus, a plurality of packets sorted, ITU-T Recommendation I.
Encapsulation in AAL type 5 which is a protocol specified in 363.5, and adding a new cell including header information of a connectionless transfer protocol generated based on header information of the packet before cellization. As a result, the new cell is positioned at the head, and a plurality of A
Performs encapsulation into a packet of a connectionless transfer protocol having a format in which packets of AL type 5 format are arranged in a cell, and transfers the encapsulated packet to the packet relay device. Receiving a packet of the connectionless transfer protocol, transferring the packet of the connectionless transfer protocol to a next packet relay device or a user network accommodating device according to header information included in a head cell, and In the user network accommodating apparatus that has received the packet of the transfer protocol, the cell containing the header information of the connectionless transfer protocol is removed from the packet of the connectionless transfer protocol. 5. An IP packet transfer method, comprising: decapsulating a packet of a plurality of packets in a format of 5 into a plurality of packets, separating each of the packets of the AAL type 5 into a single packet, and transferring the packet to a user network. 2. A user network accommodating device for accommodating a plurality of user networks via a plurality of ports and encapsulating and transferring IP packets transferred from the user networks into a connectionless transfer protocol different from IP, An IP packet transfer device in an IP packet transfer network for connecting a packet relay device performing transfer using the connectionless transfer protocol in a network form by a communication link and dividing a frame into cells of a fixed length. The user network accommodating apparatus for transferring a packet from a network to an IP packet transfer network, converts a packet received from the user network from the IP packet transfer network to the user network by using header information. At least 1 through which is
One user network accommodating device is determined, distributed to each user network accommodating device, and the distributed packets are transmitted to ITU-T Recommendation I.T. Encapsulation in AAL type 5 which is a protocol specified in 363.5, and adding a new cell including header information of a connectionless transfer protocol generated based on header information of the packet before cellization. , The new cell is located at the beginning, and a plurality of AAL type 5
Encapsulation means for encapsulating into a packet of a connectionless transfer protocol having a format in which packetized packets of a format are arranged; a first transfer means for transferring the encapsulated packet to the packet relay device; When the connectionless transfer protocol packet is received from the packet relay device, the AAL type 5 format packet is converted into a cell by removing cells including header information of the connectionless transfer protocol from the connectionless transfer protocol packet. AAL type 5
Decapsulating means for separating each type of packet into a single packet, and second transferring means for transferring the separated packet to a user network, wherein the packet relay device comprises: And a relay unit for receiving a packet of the connectionless transfer protocol and transferring the packet of the connectionless transfer protocol to a next packet relay device or a user network accommodating device based on header information included in a head cell. Packet transfer device. 3. A user network accommodating device for accommodating a plurality of user networks via a plurality of ports and encapsulating and transferring IP packets transferred from the user networks into a connectionless transfer protocol different from IP, An IP mounted on the user network accommodating device in an IP packet transfer network for connecting a packet relay device performing transfer using the connectionless transfer protocol in a network form by a communication link and dividing a frame into cells of a fixed length. A storage medium storing a packet transfer program, wherein at least one packet passing a packet received from the user network is transferred from the IP packet transfer network to the user network according to header information.
One user network accommodating device is determined, distributed to each user network accommodating device, and the distributed packets are transmitted to ITU-T Recommendation I.T. Encapsulation in AAL type 5 which is a protocol specified in 363.5, and adding a new cell including header information of a connectionless transfer protocol generated based on header information of the packet before cellization. , The new cell is located at the beginning, and a plurality of AAL type 5
An encapsulation process of encapsulating a packet of a packet of a format into a packet of a connectionless transfer protocol having a format in which cells are arranged, a first transfer process of transferring the encapsulated packet to the packet relay device, When the connectionless transfer protocol packet is received from the packet relay device, the AAL type 5 format packet is converted into a cell by removing the cell including the connectionless transfer protocol header information from the connectionless transfer protocol packet. AAL type 5
A storage medium storing an IP packet transfer program, comprising: a decapsulation process for separating packets of each type into a single packet; and a second transfer process for transferring the separated packets to a user network.