JPH1013904A - Mobile packet communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently use a finite packet address by dynamically allocating the packet address by a switching center, only when packet communication is performed. SOLUTION: A mobile packet switched network is connected to a fixed packet switched network 4, through a gateway interchange switching center 30, by which packet switching can be made not only between mobile communication terminals 1 and 2 but also between the terminals 1 and 2 and a fixed communication terminal 5. A dynamic packet address allocating part(DPA allocating part) of the center 30, dynamically allocates a packet address to each terminal 1 and 2. That is, it allocates a packet address to a mobile communication terminal which is going to start the packet communication and frees the the address allocation, when the terminal completes the packet communication. Therefore, a packet address is allocated only to the mobile communication terminal which performs the packet communication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mobile packet communication system for performing mobile communication by packet switching.

[0002]

2. Description of the Related Art In recent years, in the field of mobile communication, various mobile packet communication systems for performing data communication by packet switching have been developed. FIG. 1 shows a configuration example of a mobile packet communication system when a fixed communication terminal and a mobile communication terminal communicate. The mobile communication terminals 1, 2,... Capable of performing packet communication, and the local exchanges that control the service areas 21, 22,... Of the mobile communication terminals 1, 2,. (Hereinafter referred to simply as exchange.)
1, 32,... And another gateway switching center 30 connected to another packet switching network 4. The mobile communication terminals 1, 2,... Belong to the packet switching network 4, are assigned packet addresses that are not duplicated in the packet switching network 4, and belong to the packet switching network 4 via the gateway relay switching center 30. Exchange packets with other communication terminals.

FIG. 2 is a block diagram showing a configuration example of the gateway relay exchange 30 in the system shown in FIG. As shown in the figure, the gateway switching center 30 includes a packet transceiver 30a for transmitting and receiving packets to and from the packet switching network 4 and the switching centers 31, 32,. , And a fixed packet address management unit 30b that manages the packet addresses assigned to.

In such a mobile packet communication system, when the mobile communication terminal 1 starts packet communication with the fixed communication terminal 5 belonging to the same packet switching network 4, it is assigned to the fixed communication terminal 5 as a destination packet address. The packet is transmitted by designating the address and the address assigned to the own terminal as the source packet address. The gateway relay exchange 30 determines that the destination of the packet sent from the mobile communication terminal 1 is the fixed communication terminal 5.
The packet is sent to the packet switching network 4 because the address is assigned to the packet switching network 4. Conversely, when the fixed communication terminal 5 transmits a packet to the mobile communication terminal 1,
The gateway relay exchange 30 receiving the packet determines the location of the mobile communication terminal 1 because the destination is the address assigned to the mobile communication terminal 1, and sends the packet to the serving exchange 31. Send. Then, the serving switching center 31 transmits the received packet to the mobile communication terminal 1.

[0005]

In the above-mentioned conventional system, a packet address is fixedly assigned to each mobile communication terminal in advance. For this reason, packet addresses are uniformly assigned to not only mobile communication terminals that are currently performing packet communication but also mobile communication terminals that are not performing packet communication, and finite packet addresses are wasted. There were drawbacks.

The present invention has been made under such a background, and has as its object to provide a mobile packet communication system capable of efficiently using a finite packet address.

[0007]

Means for Solving the Problems In order to solve the above-mentioned problems, the invention according to claim 1 comprises a plurality of mobile communication terminals and an exchange which manages these mobile communication terminals.
In a mobile packet communication system in which each mobile communication terminal exchanges packets via the exchange, the exchange includes:
The mobile communication terminal that starts packet communication allocates a packet address to be used by the mobile communication terminal as its own address in the packet communication, and deallocates the packet address to the mobile communication terminal that ends packet communication. It is characterized by:

The invention according to claim 2 comprises a plurality of mobile communication terminals and an exchange which manages these mobile communication terminals and relays the exchange of packets between other packet exchange networks. In a mobile packet communication system in which mobile communication terminals exchange packets with each other via the exchange, and exchange packets with communication terminals belonging to the other packet switching network, the exchange performs packet communication. The mobile communication terminal to start is assigned a packet address used by the mobile communication terminal as its own address in the packet communication, while the packet address is released to the mobile communication terminal to end the packet communication. And

According to a third aspect of the present invention, there is provided a mobile communication terminal, a local exchange which manages a service area of the mobile communication terminal, and a packet exchange between the exchange and another packet switching network. Each mobile communication terminal exchanges packets with each other via the subscriber exchange and the gateway exchange, and belongs to the other packet switching network. In the mobile packet communication system for exchanging packets between the mobile relay terminal and the mobile relay terminal that starts packet communication, the gateway relay switching center transmits a packet address used by the mobile communication terminal as its own address in the packet communication. While allocating, to mobile communication terminals that end packet communication,
It is characterized in that the assignment of the packet address is released.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. A: Configuration of Embodiment In this embodiment, the present invention is applied to a packet switching network having the same form as the conventional system shown in FIG. That is, also in the present embodiment, the mobile packet switching network
It is connected to the fixed packet switching network 4 via the gateway switching center 30 ', thereby enabling packet switching not only between mobile communication terminals but also between fixed communication terminals. The difference between this embodiment and the conventional system shown in FIG. 1 lies in the function of the gateway relay exchange 30 '. Other parts are the same as those of the conventional system shown in FIG.

FIG. 3 is a block diagram showing the configuration of the gateway switching center 30 'according to the present embodiment. As shown in this figure, the gateway switching center 30 '
0a, a fixed packet address management unit 30b, a dynamic packet address allocation unit (hereinafter abbreviated as DPA allocation unit) 30c, and a dynamic packet address management unit (hereinafter abbreviated as DPA management unit) 30d.

The packet transceiver 30a and the fixed packet address management unit 30b have the same configuration as the conventional system shown in FIG. However, the fixed packet address management unit 30b manages only fixedly assigned packet addresses. On the other hand, the assignment of the packet address to the mobile communication terminals 1, 2, ... in the mobile packet switching network is performed by the DPA allocating unit 30c. Note that the packet address is a unique address for the entirety of the fixed packet switching network 4 and the mobile packet switching network as a whole, and does not overlap with each other as in the above-described conventional system.

The DPA allocating unit 30c dynamically allocates a packet address to each of the mobile communication terminals 1, 2,.... That is, a packet address is assigned to a mobile communication terminal that is about to start packet communication, and the address assignment is released when the packet communication ends. As a result, a packet address is assigned only to a mobile communication terminal that is performing packet communication.

The DPA management unit 30d holds an address management table indicating which packet address is currently allocated to which mobile communication terminal, and updates the contents of this table as needed based on the allocation result by the DPA allocation unit 30c. I do. On the other hand, the fixed packet address management unit 30b also holds the address management table in the same manner. However, since the address assignment is fixed, the content is not updated unless the terminal is added or the like. The packet transceiver 30a refers to an address management table held by the DPA management unit 30d and the fixed packet address management unit 30b, and performs packet routing control and the like.

B: Operation of Embodiment Next, the operation of the embodiment having the above configuration will be described with reference to the sequence diagram shown in FIG. As shown in the figure, first, when the mobile communication terminal 1 starts packet communication with the fixed communication terminal 5, the gateway relay exchange 30 ′ connected to the fixed packet switching network 4 An address assignment request is made (step S1). Upon receiving the packet address assignment request, the gateway switching center 30 'searches for a packet address to which no assignment has been made, and notifies the mobile communication terminal 1 of the packet address (step S2).

The mobile switching center 1 having received the packet address assignment designates the address assigned to the fixed communication terminal 5 as the destination packet address and the address assigned to the terminal itself as the source packet address. Then, the packet is transmitted to the gateway relay exchange 30 '(step S3).

Next, upon receiving the packet, the gateway switching center 30 'sends the packet to the packet switching network 4 because the destination of the packet is the address assigned to the fixed communication terminal 5 (step). S4). Thus, the transmission of the packet from the mobile communication terminal 1 to the fixed communication terminal 5 is completed.

On the other hand, from the fixed communication terminal 5 to the mobile communication terminal 1
When the packet is transmitted to the destination, the packet is received by the gateway switching center 30 'via the packet switching network 4 (step S5). Since the destination of the packet is a dynamically assigned packet address, the gateway relay exchange 30 'finds the mobile communication terminal 1 to which the address is assigned according to the address management table of the DPA management unit 30d, and performs mobile communication. The location of the terminal 1 is determined. Then, the gateway relay exchange 30 'transmits the packet to the mobile communication terminal 1 via the serving exchange 31 of the mobile communication terminal 1 (step S6). Thus, mobile communication terminal 1 receives the packet transmitted from fixed communication terminal 5.

When the mobile communication terminal 1 terminates the packet communication, it requests the gateway relay exchange 30 'to which the packet address has been assigned to release the packet address (step S7). Upon receiving the packet address release request, the gateway relay switching center 30 'releases the packet address assigned to the mobile communication terminal 1, and notifies the mobile communication terminal 1 that the release has been completed (step S8). Thus, the mobile communication terminal 1 ends the packet communication.

Thereafter, upon receiving a packet address assignment request from another mobile communication terminal, the gateway relay switching center 30 'transfers the packet address previously assigned to the mobile communication terminal 1 to the requesting mobile communication terminal. It becomes possible to assign.

C: Modifications The present invention is not limited to the above-described embodiment, but includes, for example, the following modifications. (1) The present invention is not limited to the embodiment shown in FIG. 1, but can be applied to other types of packet switching networks. For example, the present invention employs a fixed packet switching network 4 as in the embodiment.
It is also applicable to systems closed in a mobile packet switching network that are not connected to the network.

(2) Also, as in the embodiment, a node for allocating / managing packet addresses may be provided separately without allocating / managing packet addresses in the gateway relay exchange 30 '. Good. Further, for example, when the present invention is applied to a closed system in a mobile packet switching network, the local exchange may assign / manage packet addresses.

(3) The present invention is not limited to the case where all of the mobile communication terminals 1, 2,... Belonging to the mobile packet switching network are dynamically assigned packet addresses. The present invention can be applied to a case where terminals to be allocated are mixed. In this case, the fixed packet address management unit 30b manages addresses for mobile communication terminals to which packet addresses are fixedly assigned, and the DPA management unit 30d manages addresses for mobile communication terminals to which packet addresses are dynamically assigned. Do.

(4) In the embodiment, the case where the mobile communication terminal 1 transmits a packet to the fixed communication terminal 5 to which the packet address is fixedly assigned is described as an example.
For example, when transmitting a packet to a communication terminal (for example, mobile communication terminal 2) to which a packet address is dynamically assigned similarly to the own terminal, the mobile communication terminal 1 does Should be obtained by inquiring of the gateway relay exchange 30 '.

(5) Further, in the embodiment, the type of data to be exchanged in a packet is not particularly mentioned. However, the present invention is not limited to so-called character data, and various types of data such as voice or image digitized data are used. Target data.

[0026]

As described above, according to the present invention, a mobile communication terminal can be dynamically assigned a packet address by an exchange only when performing packet communication, and needs a packet address while not performing packet communication. Therefore, there is no need to prepare packet addresses corresponding to the numbers of all mobile communication terminals, and an effect that a finite packet address can be used efficiently can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of a mobile packet communication system when a fixed communication terminal and a mobile communication terminal communicate with each other.

FIG. 2 is a block diagram showing a configuration example of a conventional gateway relay exchange 30 applied to the system shown in FIG.

FIG. 3 is a block diagram showing a configuration of a gateway switching center 30 'according to an embodiment of the present invention applied to the system shown in FIG. 1;

FIG. 4 is a sequence diagram for explaining an operation in the embodiment.

[Explanation of symbols]

 1, 2 mobile communication terminal 4 fixed packet switching network 5 fixed communication terminal 30 'gateway relay exchange 31, 32 subscriber exchange 30a packet transceiver 30b fixed packet address management unit 30c dynamic packet address allocation unit 30d dynamic packet address management unit

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Katsushi Nakamura 2-10-1 Toranomon, Minato-ku, Tokyo Inside NTT Mobile Communication Network Co., Ltd.

Claims (3)

[Claims] 1. A mobile packet communication system comprising a plurality of mobile communication terminals and an exchange for managing these mobile communication terminals, wherein each mobile communication terminal exchanges packets via said exchange. , A mobile communication terminal that starts packet communication allocates a packet address to be used by the mobile communication terminal as its own address in packet communication, and releases a packet address allocation to a mobile communication terminal that ends packet communication. A mobile packet communication system, comprising: 2. A mobile communication terminal comprising: a plurality of mobile communication terminals; and an exchange that manages the mobile communication terminals and relays exchange of packets between the mobile communication terminals and another packet switching network. A mobile packet communication system that exchanges packets with one another and exchanges packets with communication terminals belonging to the other packet switching network via the mobile station. A mobile packet communication system, wherein the mobile communication terminal assigns a packet address to be used as an address of the terminal itself in the packet communication, and releases the assignment of the packet address to the mobile communication terminal that ends the packet communication. 3. A plurality of mobile communication terminals, a subscriber exchange which manages an area where the mobile communication terminals are located, and a gateway relay exchange which relays packet exchange between the exchange and another packet switching network. And each mobile communication terminal exchanges packets with each other via the subscriber exchange and the gateway relay exchange, and also exchanges packets with communication terminals belonging to the other packet switching network. In the mobile packet communication system, the gateway relay exchange assigns, to a mobile communication terminal that starts packet communication, a packet address that the mobile communication terminal uses as its own address in the packet communication, and terminates the packet communication. A mobile packet communication system for canceling the assignment of a packet address to a mobile communication terminal.