JP2002252647A - Apparatus and method for transmitting ip packet and storage medium for storing program of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an IP packet transmitting apparatus which can narrow a total bandwidth required for an IP network to the utmost and reduce processing loads of switching apparatuses existing in the IP network. SOLUTION: A multiplexing and demultiplexing means a1 on a transmitting side creates multiplexed packets which have an IP address of a multiplexing and demultiplexing means b1 at the head, an identifier of an IP phone b4 as a destination and an IP payload additionally following when the IP packets are transmitted to the IP phone b4 belonging to the multiplexing and demultiplexing means b1 on a receiving side. The identifier is shorter than a record length of an IP header. Although there are a plurality of the IP phones b4, the packets can be multiplexed regardless of whether the IP phones b4 are identical or different as long as the IP phones b4 belong to the multiplexing and demultiplexing means b1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an IP packet transmission apparatus for transmitting an IP packet via an IP network, and related technology.

[0002]

2. Description of the Related Art Generally, when data is transmitted on an IP network, an IP packet to which a fixed length header (IP header) irrespective of the data size is added prior to actual data is used. Transmission is performed.

[0003] Therefore, an IP packet larger in size than actual data flows in the IP network.

[0004] In recent years, as a practical application using the Internet, VoIP (Voice
Voice communication using (ver IP) technology is being put to practical use. As a function required for voice communication, a device for minimizing delay time is required.

[0005] This delay time generally increases as the size of the IP packet increases. For this reason, Vo
In IP, audio data (stream) is decomposed (fragmented) into a small size (about 20 bytes), and headers (for VoIP,
An RTP header, a UDP header, and an IP header are added and transmitted.

[0006] The total length of these headers is 40 bytes. Therefore, two thirds of the 60-byte IP packet is occupied by the header.

By continuously sending a large amount of such IP packets to an IP network, the bandwidth required for voice communication is greatly increased, and a switching device (such as a router) is required due to an increase in the number of IP packets. ) Causes a problem that the processing load increases.

[0008] Such a problem is not limited to voice communication, but may occur when a header length attached to the actual data length (called a payload) to be transmitted is not sufficiently small compared with the actual data length.

As a conventional technique for solving such a problem, for example, there is an IP packet transfer method disclosed in Japanese Patent Application Laid-Open No. 2000-209228.

In this conventional IP packet transfer method, IP packets having the same IP address (the same destination) and the same prefix length are collected before transmitting them to the wide area network.

Then, the collected IP packets are
Multiplexing as a new IP packet having one IP address reduces the processing load on the router.

[0012]

SUMMARY OF THE INVENTION The above conventional I
In the P packet transfer method, multiplexing is not performed for IP packets having different IP addresses (destinations are different). That is, when transmitting a plurality of IP packets having different destinations at the same time, they cannot be multiplexed.

For this reason, there is a problem that the total bandwidth required by the IP network is still wide and the processing load of the switching device existing in the IP network is large.

SUMMARY OF THE INVENTION An object of the present invention is to provide an IP packet transmission apparatus capable of minimizing the total bandwidth required by an IP network as much as possible and reducing the processing load of a switching device existing in the IP network, and its related art. And

[0015]

In the IP packet transmission apparatus according to the present invention, a plurality of I / O packets transmitted by terminals belonging to the IP packet transmission apparatus are transmitted.
Multiplexing means for transmitting the multiplexed packet obtained by multiplexing the P packets to the IP network; and decomposing means for decomposing the multiplexed packet received via the IP network into a plurality of IP packets and transferring the plurality of IP packets to terminals belonging thereto. The multiplexing means obtains the identifier of the destination terminal and the IP address of the decomposing means having the terminal under the multiplexing packet. Of the disassembly means having a terminal under its control
A P-address, the identifier of the destination terminal,
This identifier includes a portion obtained by removing the IP header from the IP packet, and this identifier has a smaller amount of information than the IP header.

With this configuration, when transmitting an IP packet to a terminal belonging to the disassembly means, not only an IP packet having the same IP address (the same terminal as the destination) but also a different IP address (the destination and the destination). IP packets having different terminals) can be multiplexed.

As a result, the total bandwidth required by the IP network can be reduced as much as possible, and the processing load on the switching device existing in the IP network can be reduced.

[0018]

According to the first aspect of the present invention, there is provided an IP packet transmission apparatus comprising: a multiplexing unit for transmitting a multiplexed packet obtained by multiplexing a plurality of IP packets transmitted by terminals belonging to the IP network to an IP network; Decomposing means for decomposing the received multiplexed packet into a plurality of IP packets and transferring the demultiplexed packets to terminals belonging to the subordinate. And the IP address of the disassembly means having the IP address of the disassembly means having the destination terminal under its control, and the multiplexed packet has an identifier of the destination terminal, This identifier includes a portion obtained by removing the IP header from the IP packet, and this identifier has a smaller amount of information than the IP header.

According to this configuration, when transmitting an IP packet to a terminal belonging to the decomposing means, not only an IP packet having the same IP address (the same terminal as the destination) but also a different IP address (the destination and the destination). IP packets having different terminals) can be multiplexed.

As a result, the total bandwidth required by the IP network can be reduced as much as possible, and the processing load on the switching device existing in the IP network can be reduced.

[0021] In the IP packet transmitting apparatus of the second aspect, the multiplexing means adds an identifier of the destination terminal after the IP address of the decomposing means having the destination terminal under the control thereof, and further adds To the IP packet
A multiplexed packet is created by adding a part excluding the header.

With this configuration, the multiplexing means can be configured as one IP.
Every time a packet is received, an identifier and a portion excluding an IP header can be added one after another.

As a result, from the identifier and the IP packet,
There is no need to rearrange the portion excluding the P header, and the multiplexing process can be sped up. Similarly, the speed of the decomposition process can be increased.

In the third aspect of the present invention, the multiplexing means terminates creation of one multiplex packet when a predetermined time has elapsed.

With this configuration, it is possible to set a proper delay time for transmitting and receiving a multiplex packet and to maintain a constant transmission speed.

In the IP packet transmitting apparatus according to a fourth aspect, the multiplexing means terminates the creation of one multiplex packet when the record length of the multiplex packet being created exceeds a prescribed value.

According to this configuration, by determining the specified value in consideration of the maximum length of the IP packet, it is possible to prevent the created multiplex packet length from exceeding the maximum length of the IP packet.

[0028] In the IP packet transmitting apparatus according to the fifth aspect, the multiplexing means transmits the IP address to the destination terminal.
A multiplexing reference table that associates an address, an identifier thereof, and an IP address of a decomposing unit having the terminal under the control of the multiplexing unit; Based on the IP address, the identifier of the terminal and the I
The disassembly means obtains the P address, and the disassembly means has a disassembly reference table for associating the IP address, the identifier, and the IP address of the disassembly means with respect to the terminal belonging to the subordinate terminal. , The IP address of the corresponding terminal is obtained based on the identifier included in the received multiplexed packet, and the IP packet is created and transferred.

According to this configuration, the multiplexing means and the decomposing means have their own multiplexing reference table and decomposing reference table.

As a result, the speed of the multiplexing and decomposing processing can be increased as compared with the case where a dedicated server or the like is accessed and the multiplexing reference table and the decomposed reference table are used.

Hereinafter, an IP packet transmission system according to an embodiment of the present invention will be described with reference to the drawings. This IP packet transmission system is suitable for continuously transferring small-sized data, such as VoIP, for example.

FIG. 1 is a block diagram showing an IP according to an embodiment of the present invention.
FIG. 1 is a block diagram illustrating an overall configuration of a packet transmission system.

As shown in FIG. 1, the IP packet transmission system includes IP packet transmission devices A and B. The IP packet transmission apparatus A includes a multiplexing / decomposing unit a
1, a router a2, and an IP telephone (terminal) a4. The IP packet transmission device B has the same configuration.

A plurality of IP telephones a4 belong to the multiplexing / decomposing means a1, and both are connected by the private network a3. Further, the plurality of IP phones a4 have different IP addresses.

The multiplexing / decomposing means a1 is connected to the router a2, and the router a2 is connected to the IP network 1. The same applies to the connection relationship between the router B2, the multiplexing / decomposing means b1, and the plurality of IP phones b4.

Although not shown, in addition to the IP packet transmission apparatuses A and B, a plurality of IP packet transmission apparatuses having the same configuration and function are connected to the IP network 1. Similarly, a plurality of IP phones exist under the transmission device.

FIG. 2 is a block diagram of the multiplexing / decomposing means a1 of FIG. In FIG. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 2, multiplexing / decomposing means a1
Is a multiplexing / decomposition reference table a11, a multiplexing / decomposition processing unit a12, a transmission buffer a13, and a timer a1.
4 inclusive.

When transmitting data, the multiplexing / decomposing processing unit a12 converts a multiplexed packet obtained by multiplexing a plurality of IP packets transmitted by the subordinate IP telephone a4 into an IP packet.
When sending to network 1 and receiving data,
The received multiplex packet is decomposed into a plurality of IP packets and transferred to the subordinate IP telephone a4.

The multiplexing of a plurality of IP packets created by the multiplexing / decomposing processor a12 is called a "multiplexed packet".

FIG. 3 is a diagram showing an example of the data structure of an IP packet to be multiplexed. As shown in FIG. 3, the IP packet has an IP header (20 bytes), a UD
It consists of a P header (8 bytes), an RTP header (12 bytes), and a payload (about 20 bytes). In addition, Vo
An IP packet in the case of IP has a data configuration shown in FIG.

Hereinafter, the portion obtained by removing the IP header from the IP packet will be referred to as “IP payload”.

Unless otherwise indicated, the IP packet transmitting apparatus A and the IP telephone a4 are connected to the transmitting side and the I
The P packet transmission device and the IP telephone are the receiving side. For example, the IP packet transmission device B and the IP phone b4 are receivers.

Accordingly, the multiplexing / decomposing means on the receiving side may be referred to as a “destination device”, and the multiplexing / decomposing means A1 on the transmitting side may be referred to as a “own device”.

The multiplexing / decomposition reference table a shown in FIG.
11 is an IP telephone (terminal) located on the receiving side,
The identifier (ID), the IP address, and the IP
It has a record in which the IP address (the IP address of the destination device) of the multiplexing / decomposing means under the telephone is paired.

For example, the multiplexing / decomposition reference table is represented by I
The P telephone b4 has a record in which the identifier, the IP address, and the IP address of the multiplexing / decomposing means b1 having the IP telephone b4 are set.

The transmission buffer a13 temporarily stores data at the time of multiplexing. The timer a14 notifies the multiplexing / decomposing unit a12 of the end of the multiplexing process.

The multiplexing / decomposing reference table a11 stores the multiplexing / decomposing means a1 in case of the receiving side.
And the identifier (ID) of the IP phone a4 belonging to
IP address of telephone a4 and I of multiplexing / decomposing means a1
It also has a record in which a P address (the IP address of its own device) is paired.

The configuration and functions of the multiplexing / decomposing means b1 are the same as those of the multiplexing / decomposing means a1.

Next, referring to FIG. 1, FIG. 2, FIG. 3, and FIG. 4 showing the data structure of the multiplex packet (record of the multiplex packet created in the transmission buffer), the present embodiment will be described. The multiplexing process will be briefly described. Note that, again, the multiplexing / decomposing means a1 and the like will be described as the transmitting side, and the multiplexing / decomposing means b1 and the like will be described as the receiving side.

First, when the multiplexing / decomposing processing unit a12 receives an IP packet from the IP telephone a4, which is the transmission source, the multiplexing / decomposing reference table a11 is used for the destination IP telephone (terminal). Based on the IP address of b4, an identifier (ID) of the IP telephone b4 and an IP address of the multiplexing / decomposing means b1 having the IP telephone b4 (an IP address of the destination device) are obtained.

Next, the multiplexing / decomposing processing unit a12
As shown in (1), the IP address (IP address of the destination device) of the multiplexing / decomposing means b1 having the IP telephone b4 as the destination under the head is first, and thereafter, the IP telephone b4 as the destination is An identifier (ID) is added, and thereafter, an IP payload (a part obtained by removing an IP header from an IP packet) is added.

Thereafter, the identifier and the IP payload of the IP telephone b4 belonging to the multiplexing / decomposing means b1 are added.

If the IP telephone b4 belonging to the multiplexing / decomposing means b1 is a destination, it can be added even if the IP address of the IP telephone b4 is different. That is, IP phone b
Although there are a plurality of IP phones b4, as long as the IP phone b4 belongs to the multiplexing / decomposing means b1, multiplexing can be performed not only when the IP phone b4 is the same but also when the IP phone b4 is different.

The multiplexing / decomposing unit a12 determines whether an interruption by the timer a14 occurs (when the time set in the timer a14 has elapsed) or whether the record length of the multiplexed packet exceeds a specified value. At this time, the creation of one multiplex packet is completed.

The time set in the timer a14 is calculated from the delay time allowed for the transmission and reception of general IP packets without multiplexing. The specified value is I
It is determined based on the maximum length allowed for the P packet.

The identifier of the IP telephone b4 has a record length shorter than the IP header of the IP packet (see FIG. 3). The same applies to the identifier of the IP phone a4.

Next, the details of the multiplexing process described above will be described with reference to the flowchart of FIG. Note that, again, the multiplexing / decomposing means a1 and the like will be described as the transmitting side, and the multiplexing / decomposing means b1 and the like will be described as the receiving side (destination side).

In step 1, if the condition of * 1 is not satisfied, the process proceeds to step 2. That is, step 1
If the interrupt by the timer a14 does not occur and the multiplex packet length does not exceed the specified value, the process proceeds to step 2.

In step 2, the multiplexing / decomposing unit a12 sends the I
The IP packet transmitted by the P telephone a4 is received.

Then, the multiplexing / decomposing unit a12 obtains the IP address of the destination IP telephone b4 indicated in the received IP packet.

In step 3, the multiplexing / decomposing processor a12 refers to the multiplexing / decomposing reference table a11, and the multiplexing / decomposing means having the identifier of the destination IP telephone b4 and the IP telephone b4 under its control. Attempt to obtain the IP address of b1 (the IP address of the destination device).

If the acquisition fails, the IP address of the destination IP telephone b4 is stored in the multiplexing / decomposition reference table a11.
Multiplexing / decomposing unit a12
Discards the IP packet (steps 4 and 5) and proceeds to step 1.

When the acquisition has failed, the multiplexing / decomposing unit a12 may send the IP packet to the IP network 1 via the router a2 instead of discarding the IP packet.

If the acquisition is successful, the process proceeds to step 6 (step 4).

In step 6, the multiplexing / decomposing section a12 outputs the multiplexing / decomposing means b1 obtained in step 3.
Record having the IP address of the transmission buffer a13
To see if it already exists.

If it is determined in step 7 that a record exists, the process proceeds to step 8. In step 8, the multiplexing / decomposing unit a12 deletes the IP header from the IP packet received in step 2 to obtain an IP payload (see FIG. 3).

Then, after the record (including the IP address of the multiplexing / decomposing means b1) obtained by the retrieval in step 6, the multiplexing / decomposing processing section a12 outputs the IP telephone b4 obtained in step 3 An identifier and an IP payload are added as a pair.

For example, as shown in the multiplexing / decomposition reference table a11 in FIG. 2, when the IP address of the destination IP telephone b4 is “132.182.101.
The identifier of the P telephone b4 is "1", and the IP address of the multiplexing / decomposing means b1 having the IP telephone b4 under its control is "132.
182.1.1 "(step 3).

In this case, the identifier “1” of the IP phone b4 is added to the end of the record shown in FIG.
Add an IP payload (step 8). Then, the process proceeds to step 1.

On the other hand, in step 7, the multiplexing / decomposing means b1 obtained in step 3 is stored in the transmission buffer a13.
If there is no record having the IP address, the process proceeds to step 9.

In step 9, the multiplexing / decomposing unit a12 outputs the multiplexing / decomposing means b1 obtained in step 3.
A record is newly created with an IP header including the IP address at the top.

Then, the process proceeds to a step 8, wherein an IP header having the IP address of the multiplexing / decomposing means b1 is added to the IP header.
The identifier of the telephone b4 and the IP payload are added. Then, the process proceeds to step 1.

It should be noted that there are a plurality of IP telephones b4, but if the multiplexing / decomposing means b1 to which they belong is the same, even if the destination IP telephones b4 have different identifiers, the multiplexing / decomposing means b1 may be different. After the IP address of the decomposing unit b1, the identifier and the IP payload of the IP phone b4 are added.

In step 1, if the condition of * 1 is satisfied, the process proceeds to step 10. That is, if an interrupt by the timer a14 is entered in step 1 or if the multiplex packet length exceeds the specified value, the multiplexing (creation of one multiplex packet) is terminated, and step 10
Proceed to.

At step 10, the multiplexing / decomposing unit a12 outputs the multiplexed packet created in the transmission buffer a13 to the router a2.

In step 11, the multiplexing / decomposing unit a12 initializes the timer a14, and proceeds to step 1.

Multiplexing is performed by repeating the above.
As shown in Step 1, there are two types of multiplexing end conditions.

One is when the length of at least one record (multiplexed packet) in the transmission buffer a13 exceeds a prescribed value, and the other is when a multiplexing end signal is received from the timer a14. is there.

The specified value is determined based on the maximum length (65,536 bytes including the header) allowed for an IP packet, and the created multiplex packet length is determined by the maximum length allowed for an IP packet. Is determined not to exceed.

By determining the specified value in this way, it is possible to reliably prevent the created multiplex packet length from exceeding the maximum length allowed for the IP packet.

The meaning of the termination by the timer a14 is to designate the maximum allowable time of one multiplexing process (one multiplexed packet creation), and to control the delay time at the time of transmission / reception. For example, when the delay time exceeds the allowable range, the delay time can be reduced by reducing the time set in the timer a14.

Next, the details of the multiplex packet decomposing process will be described with reference to the flowchart of FIG.

In step 21, upon receiving the multiplexed packet of the format shown in FIG. 4 from the IP network 1, the multiplexing / decomposing means b1 deletes the leading IP header.

If it is determined in step 22 that there is an object to be disassembled (when the disassembly processing of the received multiplex packet has not been completed), the process proceeds to step S23.

In step 23, the multiplexing / decomposing means b1 acquires the identifier of the IP telephone b4 written at the head of the remaining fields.

In step 24, the multiplexing / decomposing means b1 refers to the multiplexing / decomposition reference table of the IP packet transmitting apparatus B and refers to the IP telephone b of the transmission destination (destination).
4 is obtained.

At step 25, the multiplexing / decomposing means b1 obtains the leading IP payload from the multiplexed packet (step 21) from which the IP header has been deleted.

Then, the multiplexing / decomposing means b1 outputs the IP address of the IP telephone b4 of the transmission destination (destination) acquired in step 24.
An IP packet to be transmitted to the destination (destination) IP telephone b4 is created from the address and the leading IP payload.

In step 26, the multiplexing / decomposing means b1 converts the created IP packet into the private network b3.
Via the multiplexing / decomposing means b1 to the destination IP telephone b4.

After the processing of step 26 is completed, the process proceeds to step 22. In step 22, when there is no decomposition target (when there is no data to be processed), the decomposition of one multiplex packet is ended. By repeating the above process, the multiplex packet can be decomposed.

FIG. 7 shows a multiplexing / decomposing unit a12.
FIG. 9 is a diagram showing another example of the data configuration of a multiplexed packet created by.

As shown in FIG. 7, the multiplexing / decomposing means b1
Including the IP address of the device (the IP address of the destination device)
Header, followed by a plurality of I
Add a summary of identifiers (ID) of P-phone b4,
Thereafter, a multiplexed packet can be created by adding a combination of a plurality of IP payloads.

However, the multiplexed packet to be created preferably has the data structure shown in FIG. 4 for the following reason.

With the data configuration as shown in FIG. 7, when multiplexing, it is necessary to rearrange the identifiers such as combining a plurality of identifiers into one for the IP packets received one after another. Processing becomes complicated. In the case of disassembly, the processing is similarly complicated.

On the other hand, if the data configuration as shown in FIG. 4 is adopted, in the case of multiplexing, each time the multiplexing / decomposing means a1 receives one IP packet, an identifier and an IP payload are added one after another. it can.

As a result, there is no need to rearrange a plurality of identifiers or a plurality of IP payloads, and the multiplexing process can be sped up. Similarly, the speed of the decomposition process can be increased.

As described above, in the present embodiment,
When performing multiplexing, the multiplexing / decomposing means a1 identifies the identifier of the IP telephone b4 as a destination and the IP of the multiplexing / decomposing means b1 having the IP telephone under its control.
And get the address.

The multiplexing / decomposing means a1 starts with the IP address of the multiplexing / decomposing means b1 having the destination IP telephone b4 under its control, and thereafter, the destination IP telephone b4 A multiplexed packet is created by adding the identifier of the IP address and the IP payload.

With this configuration, when the multiplexing / decomposing means a1 on the transmitting side transmits an IP packet received from an IP telephone a4 belonging to the transmitting side via the IP network 1, the destination IP telephone b4 Is under the control of the multiplexing / decomposing means b1 on the receiving side, not only IP packets having the same IP address (the same destination IP telephone b4) but also different IP addresses (the destination IP telephone b4) b4 is different).

Further, the identifier of the IP telephone b4 has a record length shorter than the IP header of the IP packet (see FIG. 3). Therefore, when comparing the case where the same number of IP packets are transmitted without multiplexing and the case where multiplexed transmission is performed, the total number of packets to be transmitted is smaller when multiplexed and transmitted.

As a result, the total bandwidth required by the IP network 1 can be minimized and the IP network 1
The processing load of the switching device existing in the system can be reduced.

The multiplexing / decomposing means a1 determines whether a predetermined time has elapsed (when an interrupt is generated by the timer a14) or the record length of the multiplex packet exceeds a specified value. The creation of one multiplex packet ends.

As described above, when the predetermined time has elapsed, the creation of one multiplexed packet is completed, so that the delay time in transmitting and receiving the multiplexed packet can be made appropriate, and the fixed transmission speed can be reduced. Can hold.

When the record length of the multiplex packet exceeds the specified value, the creation of one multiplex packet is terminated. The packet length can be prevented from exceeding the maximum length of the IP packet.

Further, the multiplexing / decomposing means a1 itself
It has a multiplexing / decomposition reference table a11. As a result, the speed of the multiplexing and decomposition processing can be increased as compared with the case where the dedicated server or the like is accessed and the multiplexing / decomposition reference table is used.

Note that the receiving-side IP packet transmission apparatus
When transmitting an IP packet to a plurality of IP telephones belonging to different IP packet transmission apparatuses, the multiplexing / decomposing means a1 on the transmitting side sets different multiplexing / decomposing means (for each different IP packet transmitting apparatus). ), Multiplex packets will be created.

In the present embodiment, the terminal device connected to the private networks a3 and b3 is an IP telephone a.
4, b4 is used, but other devices may be used as long as they are terminal devices for transmitting and receiving IP packets.

In the above description, for convenience of explanation, the IP packet transmitting apparatus A is assumed to be a transmitting side, and the receiving side is particularly required to be an IP packet transmitting apparatus A.
Although the description has been made focusing on the P packet transmission apparatus B,
The P packet transmission device can perform multiplexing processing when it is on the transmitting side, and can perform decomposing processing when it is on the receiving side.

When the multiplexing / disassembling reference table of any one of the IP packet transmitting apparatuses is updated, the multiplexing / disassembling reference table of each IP packet transmitting apparatus is updated via the IP network 1. .

Further, a server having a multiplexing / decomposing reference table may be connected to the IP network 1 and the multiplexing / decomposing reference table may be used by accessing this server.

Further, there are two layers (multiplexing / decomposing means and I
Although the case of P-phone has been described, the number of layers may be further increased.

[0113]

According to the first, sixth and eleventh aspects of the present invention, when an IP packet is transmitted to a terminal belonging to the decomposing means, the same IP address (the destination terminal is the same).
Not only IP packets having different IP addresses (terminals having different destinations) can be multiplexed.

As a result, the total bandwidth required by the IP network can be reduced as much as possible, and the processing load on the switching device existing in the IP network can be reduced.

According to the second and seventh aspects of the present invention, the multiplexing means includes one unit.
Each time one IP packet is received, an identifier and a portion excluding the IP header can be added one after another.

As a result, from the identifier and the IP packet, the IP
There is no need to rearrange the portion excluding the header, and the multiplexing process can be sped up. Similarly, the speed of the decomposition process can be increased.

According to the third and eighth aspects of the present invention, the delay time at the time of transmitting / receiving a multiplex packet can be made appropriate.
Constant transmission speed can be maintained.

According to the fourth and ninth aspects of the present invention, by determining the prescribed value in consideration of the maximum length of the IP packet, it is possible to prevent the length of the created multiplex packet from exceeding the maximum length of the IP packet.

According to the fifth and tenth aspects of the present invention, the multiplexing means and the decomposing means have their own multiplexing reference table and decomposing reference table.

As a result, the speed of multiplexing and decomposing can be increased as compared with the case where a dedicated server or the like is accessed and the multiplexing reference table and the decomposed reference table are used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an IP packet transmission system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a multiplexing / decomposing means of FIG. 1;

FIG. 3 is a diagram showing a data structure of an IP packet.

FIG. 4 is a diagram showing a data structure of a multiplexed packet.

FIG. 5 is a flowchart showing a multiplexing procedure;

FIG. 6 is a flowchart showing a procedure of disassembly.

FIG. 7 is a diagram showing another example of the data structure of a multiplex packet.

[Explanation of symbols]

 A1, B1 IP packet transmission device a1, b1 Multiplexing / decomposing means a2, b2 Router a3, b3 Private network a4, b4 IP telephone a11 Multiplexing / disassembling reference table a12 Multiplexing / disassembling processing unit a13 Transmission buffer a14 Timer 1 IP network

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ikuji Shimizu 1006 Kazuma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. F term (reference) 5K030 GA08 HA08 HC01 HC14 HD03 HD06 JA01 JA05 JT01 KX02 5K033 AA03 CB08 DA06 DB17 DB18

Claims (11)

[Claims] 1. A multiplexing means for transmitting a multiplexed packet obtained by multiplexing a plurality of IP packets transmitted by a terminal belonging thereto to an IP network, and decomposing the multiplexed packet received via the IP network into a plurality of IP packets. do it,
An IP packet transmission device comprising: a decomposing unit that transfers the terminal to a subordinate terminal; wherein the multiplexing unit includes, for a terminal serving as a destination, an identifier of the terminal, an IP address of the decomposing unit having the terminal under the subordinate. The head of the multiplexed packet is the IP address of a decomposing unit having a terminal that is a destination under the multiplexed packet,
The ID of the destination terminal and the IP packet
An IP packet transmission device comprising: a part excluding a P header, wherein the identifier has a smaller amount of information than the IP header. 2. The multiplexing means adds an identifier of a destination terminal after the IP address of the decomposing means having a destination terminal under its control, and further thereafter, an IP packet 2. The IP packet transmission apparatus according to claim 1, wherein the multiplexed packet is created by adding a portion excluding a header. 3. The IP packet transmission apparatus according to claim 1, wherein said multiplexing means terminates creation of one multiplexed packet when a predetermined time has elapsed. 4. The IP according to claim 1, wherein said multiplexing means terminates creation of one multiplex packet when the record length of the multiplex packet being created exceeds a prescribed value. Packet transmission device. 5. The multiplexing means has a multiplexing look-up table in which a destination terminal is associated with its IP address, its identifier, and the IP address of a decomposing means having the terminal under its control. The multiplexing means uses the multiplexed lookup table,
Based on the IP address of the destination terminal, the identifier of the terminal and the I
And a P address, and the decomposing unit obtains an IP address of a terminal belonging to
An address, an identifier thereof, and a disassembly reference table that associates the IP address of the disassembly unit with the disassembly unit, using the disassembly reference table, based on an identifier included in the received multiplexed packet, 5. The IP packet transmission device according to claim 1, wherein an IP address of a corresponding terminal is obtained, and an IP packet is created and transferred. 6. A multiplexing means for transmitting a multiplexed packet obtained by multiplexing a plurality of IP packets transmitted by a terminal belonging thereto to an IP network, and decomposing the multiplexed packet received via the IP network into a plurality of IP packets. do it,
And disassembling means for transferring to a terminal belonging to the subordinate.
An IP packet transmission method for transmitting a P packet, wherein the multiplexing unit acquires an identifier of a destination terminal and an IP address of a decomposing unit having the terminal under the multiplexing unit. Is the IP address of the decomposing means whose head is the subordinate of the destination terminal,
The ID of the destination terminal and the IP packet
And a part excluding a P header, wherein the identifier has a smaller amount of information than the IP header. 7. The multiplexing means adds an identifier of the destination terminal after the IP address of the decomposing means having the destination terminal under the control thereof, and further, after that, demultiplexes the IP packet from the IP packet. 7. The IP packet transmission method according to claim 6, wherein the multiplexed packet is created by adding a portion excluding a header. 8. The IP packet transmission method according to claim 6, wherein said multiplexing means terminates creation of one multiplexed packet when a predetermined time has elapsed. 9. The IP according to claim 6, wherein said multiplexing means terminates creation of one multiplex packet when the record length of the multiplex packet being created exceeds a prescribed value. Packet transmission method. 10. The multiplexing means has a multiplexing lookup table in which, for a terminal as a destination, its IP address, its identifier, and the IP address of a decomposing means having the terminal under its control are associated with each other. The multiplexing means uses the multiplexed lookup table,
Based on the IP address of the destination terminal, the identifier of the terminal and the I
And a P address, and the decomposing unit obtains an IP address of a terminal belonging to
An address, an identifier thereof, and a disassembly reference table that associates the IP address of the disassembly unit with the disassembly unit, using the disassembly reference table, based on an identifier included in the received multiplexed packet, 10. The IP packet transmission method according to claim 6, wherein an IP address of a corresponding terminal is obtained to generate and transfer an IP packet. 11. A method for transmitting a plurality of IPs transmitted by terminals belonging to the subordinate.
Multiplexing means for transmitting a multiplexed packet obtained by multiplexing the packets to the IP network, and disassembling means for decomposing the multiplexed packet received via the IP network into a plurality of IP packets and transferring the plurality of IP packets to terminals belonging to the multiplexed packet are arranged. A program for transmitting an IP packet, wherein the multiplexing means causes the multiplexing means to obtain an identifier of a destination terminal and an IP address of a decomposing means having the terminal under its control, , The head of which is the IP address of the disassembly means having the terminal that is the destination under it,
The ID of the destination terminal and the IP packet
A recording medium including a portion excluding a P header, and a computer-readable recording program for setting the information amount of the identifier to be smaller than the information amount of the IP header.