JP2960349B2 - Mobile communication network - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mobile communication network, and more particularly to a mobile communication network provided with a cell transfer method for realizing high-speed multimedia communication and high-speed movement using an ATM system.

[0002]

2. Description of the Related Art As a technique for efficiently transmitting multimedia information requiring various information qualities, ATM (asynchronous transfer mode in which data is transferred in a fixed length packet format having a routing header) has been studied in various fields. I have. In particular, institutions such as the ATM Forum, IETF, and ITU-T are considering transmission of the multimedia information, but have not studied mobile communication.

[0003] In addition, research on mobile communication using ATM has been conducted by AT.
& T Bell Laboratories. FIG. 2 shows a conventional ATM.
FIG. 2 is a block diagram illustrating a configuration of a mobile communication network. In FIG. 2, a PBS (PortableBase State) assigned in advance to each of the communicating terminals.
n: a switching node that performs cell routing). For example, when information is transmitted from terminal A61 to B62, terminal A61 → PBS63 connected to terminal A →
The message was sent along the path from the PBS 64 connected to the terminal B to the terminal B 62.

Here, when the terminal B62 moves, the PBS 65 connected to the destination terminal B moves to the terminal B before the movement.
The control information is exchanged with the PBS 64 connected to the terminal A, and the connection from the PBS 63 connected to the terminal A to the PBS 64 connected to the terminal B before the movement is changed to the PBS 65 connected to the terminal B of the movement destination. The transmission of information was extended. In this method, the connection becomes longer each time the terminal moves (the number of passing PBSs increases), and depending on how the terminal moves, there is a possibility that resources (connection: thick line) are wasted as shown in FIG. was there.

[0005]

As described in the above prior art, in the prior art (FIG. 2), useless resources are used depending on how the terminals move, and the number of communication terminals increases, There is a problem that if the traffic volume increases, there is a high possibility that a terminal that cannot communicate will occur.

An object of the present invention is to solve the above-mentioned problems of the prior art, and immediately after a mobile terminal moves between sub-networks, an in-network device such as an inter-network interface unit on the mobile terminal side issues a connection connection request. Do
An object of the present invention is to provide a communication network having a function of minimizing the number of passes through an ATM cell transfer device.

[0007]

According to a first aspect of the present invention, a virtual path is connected, and a plurality of transfer apparatuses for transferring a packet on the virtual path are connected by a line. In a mobile communication network in which a wireless base station that communicates with a mobile terminal is connected to a device, when the terminal moves, a transfer device connected to a destination wireless base station is
A virtual path connection request is issued to any of the transfer devices on the virtual path connected before the movement.

In the second invention, a connection request for a connection at the start of the first communication is made by the inter-network interface unit of the terminal requesting the transmission, but after the mobile terminal moves between the sub-networks, The inter-network interface unit on the mobile terminal side issues a connection request for the connection after moving to the inter-network interface unit on the other side, and establishes a new connection, thereby minimizing the number of passing ATM cell transfer devices. And saves network resources.

In a third aspect of the present invention, a predetermined database corresponding to the mobile terminal relays the connection between the terminals, and after the mobile terminal moves between the sub-networks, the inter-network interface unit on the mobile terminal side is connected. By issuing a connection request for a new connection after the transfer to the database and performing connection connection, the number of ATM cell transfer devices that pass through is reduced to save network resources, and the connection switching ( It is characterized in that the number of ATM cell transfer devices required at the time of setup at the time of (reconnection) is reduced, and the switching time is shortened.

In the fourth invention, the connection between the terminals is relayed by the database closest to the mobile terminal, and after the mobile terminal has moved between the sub-networks, the inter-network interface unit on the mobile terminal side has a new connection after the movement. By issuing a connection request for a simple connection to the database and connecting the connection, the number of ATM cell transfer devices passing through is reduced to save network resources, and the connection is switched (reconnected) according to the second invention.
It is characterized in that the number of ATM cell transfer devices required at the time of setup is reduced and the switching time is shortened.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 4 is a block diagram showing a basic configuration of a communication network to which the present invention is applied. so,
2-1 is an ATM network, 2-2 is an ATM cell transfer device, 2-3 is a line connecting the ATM cell transfer devices, 2-4 is a database for registering location information of mobile terminals, 2-5. Is an area (wireless cell) which can be covered by one wireless base station, 2-7 is a mobile terminal, 2-8 is an inter-network interface unit which is an interface between an ATM network and a sub-network. Reference numeral -9 denotes a subnetwork in which a plurality of wireless base stations are put together, and reference numeral 2-10 denotes a transmitting terminal (here, a fixed terminal is used for simplicity of description).

Further, the ATM network 2-1 has at least one database 2-4 for registering the position of each mobile terminal 2-7, and each mobile terminal 2-7 has a radio cell 2-6 or sub-cell. When moving between networks 2-9,
The location information is updated for this database.

When transmitting from the mobile terminal 2-7 to the fixed terminal 2-10, since the position of the fixed terminal is known in advance, it is sufficient to transmit to the network interface unit of the fixed terminal, and the details will not be described. Fixed terminal 2
The first to third embodiments will be described below for the case of transmitting from -10 to the mobile terminal 2-7.

FIG. 1 is an explanatory diagram for explaining the connection operation of the first embodiment. A database determined in advance corresponding to the mobile terminal 2-7a (hereinafter referred to as a home database) is designated as 2-4a. The mobile terminal moves even when not communicating, and updates the home database 2-4a with location information when moving between sub-networks (moving from 2-9a to 2-9b). For example,
When the mobile terminal 2-7a moves to the radio cell 2-6b, the inter-network interface unit 2-8b
Update the position information of the database 2-4a via the ATM cell transfer device and the line.

At this time, the inter-network interface unit 2-8b has a table as shown in FIG. 3 and caches (temporarily stores) the position information of the radio cell where the mobile terminal 2-7a is located. When the information addressed to 2-7a arrives, it is transferred to the wireless cell. When detecting the position of the mobile terminal 2-7a in the sub-network 2-9b by simultaneous paging, it is not necessary to register the position of the wireless cell in the table.

FIG. 9 is an explanatory diagram showing an operation procedure of the first embodiment. In the first embodiment, the fixed terminal side network interface unit 2-8t and the mobile terminal side network interface unit (2-8t)
It is characterized in that a direct connection is made between a and b). When the fixed terminal 2-10 transmits to the mobile terminal 2-7a, first the mobile terminal 2-4a is stored in the home database 2-4a.
It requests the current location information of the mobile terminal 2-7a and receives the location information of the mobile terminal 2-7a (in FIG. 1, it is in the subnetwork 2-9a (the wireless cell 2-6a)) (3-2).

The fixed terminal side network interface unit 2-8t is connected to the mobile terminal side network interface unit 2-8a by a connection 3-3.
And send information. Here, the details of the connection connection take a sequence as shown in FIG. 7 or FIG. In FIG. 7, the ATM VPI (virtual path identification information),
After acquiring VCI (virtual circuit identification information), a band for information transmission is secured.
At the time of securing CI, a band is also secured at the same time.

Next, when the mobile terminal 2-7a moves from the subnetwork 2-9a (wireless cell 2-6a) to the subnetwork 2-9b (wireless cell 2-6b), for example, the mobile terminal 2-7a itself The signal strength of the control channel of each wireless base station is compared, and a connection request is sent to the strongest base station (assuming that it is the base station of 2-6b). This request includes information on the partner device to be connected.

Then, the inter-network interface 2-8b that has received the connection request from the radio base station becomes the inter-network interface unit 2-8t on the fixed terminal side.
Requests connection 3-4. At this time, although not shown, the inter-network interface unit 2-8a has a timer, and when a certain period of time elapses after the mobile terminal 2-7a disappears, the old connection 3-3
, Or by sending a disconnection request notification to the inter-network interface unit 2-8t on the fixed terminal side, the old connection is disconnected.

If the new connection 3-4 can be connected, the fixed terminal side inter-network interface unit 2-8t is notified through the new connection 3-4 to use the new connection, and the fixed terminal and the mobile terminal are notified. Transmission of information between them is started. New connection 3-4
If the connection cannot be established, the connection is disconnected. According to the above method, even if the mobile terminal moves, the virtual path can always be connected via the optimal route, and the network resources can be effectively used.

FIG. 5 is an explanatory diagram for explaining the connection operation of the second embodiment. The method by which the mobile terminal registers the location information in the home database is the same as in the first embodiment, and is indicated by 4-1 and 4-2 in FIG. In this embodiment, the connection between the terminals is relayed by a predetermined database corresponding to the mobile terminal, and after the mobile terminal moves between the sub-networks, the inter-network interface unit on the mobile terminal side establishes the connection after the movement. A connection request is issued to the database to establish a connection. Therefore, network resources are saved by reducing the number of passing ATM cell transfer devices, and the number of ATM cell transfer devices required at the time of setup at the time of connection switching (reconnection) is reduced from the first embodiment. Time can be reduced.

FIG. 10 is an explanatory diagram showing the operation procedure of the second embodiment. In the present embodiment, a connection connection request to the mobile terminal 2-7a is sent to the home database 2 of the mobile terminal.
-4a performs. As a result, the network interface unit 2-8t on the fixed terminal side does not need to know the position information of the mobile terminal, and does not need to access the database at the time of the first connection connection, thereby reducing the processing load.

When the fixed terminal 2-10 transmits a message to the mobile terminal 2-7a, it first requests the home database 2-4a to establish a connection 4-3, and then requests a connection to the mobile terminal 2-7a. Receiving the request, home database 2
-4a issues a connection request for the connection 4-4 to the inter-network interface unit 2-8a on the mobile terminal side, and when the connection connection is completed, issues a connection connection permission to the inter-network interface unit 2-8t on the fixed terminal side, and Transmission starts.

Next, the mobile terminal 2-7a connects to the sub-networks 2-9a to 2-9b (the radio cells 2-6a to 2-6b).
Moving to b), the inter-network interface 2
-8b is connection 4 to home database 2-4a
The home database 2-4a issues a connection request of -5, and notifies the fixed terminal of the start of movement of the partner terminal. The fixed terminal that has received this notification stops information transmission or transmits only information that may be delayed until it receives the other terminal movement completion notification.

When the new connection 4-5 can be connected, the home database 2-4a notifies the inter-network interface unit 2-8t of the fixed terminal of the completion of the movement of the other terminal, and the information between the fixed terminal and the mobile terminal. Transmission is resumed. If the new connection 4-5 cannot be connected, the connection is disconnected. According to the above method, even if the mobile terminal moves, network resources can always be used effectively. Further, according to the above method, the connection can be switched only up to a predetermined database of the mobile terminal, so that the connection switching time can be reduced.

FIG. 6 is an explanatory diagram showing the operation procedure of the third embodiment. The method in which the mobile terminal registers the location information in the home database is the same as in the first embodiment, and
5-1 and 5-2. In the third embodiment, a plurality of databases exist in a communication network, and a connection between terminals is relayed by a database closest to the mobile terminal. Then, after the mobile terminal moves between the sub-networks, the inter-network interface unit on the mobile terminal side issues a connection request for the moved connection to the database and connects the connection. Therefore, A
Network resources can be saved by reducing the number of TM cell transfer devices, and the switching time can be reduced by reducing the number of ATM cell transfer devices required for setup at the time of connection switching (reconnection) from the second invention. it can.

FIG. 11 is an explanatory diagram showing the operation procedure of the third embodiment. When the fixed terminal 2-10 transmits to the mobile terminal 2-7a, it first requests the home database 2-4a for current location information of the mobile terminal 2-7a,
a location information (subnetwork 2-9a (wireless cell 2
-6a)), and receives the position information of the database (here, 2-4b) closest to the mobile terminal (5).
-2).

The inter-network interface unit 2-8t on the fixed terminal side issues a connection request for the connection 5-3 to the database 2-4b, and requests a connection to the mobile terminal 2-7a. Receiving the request, database 2-
4b issues a connection request for connection 5-4 to the inter-network interface unit 2-8a on the mobile terminal side, and when the connection connection is completed, issues a connection connection permission to the inter-network interface unit 2-8a on the mobile terminal side, and transmits information. Begins.

Next, the mobile terminal 2-7a connects the sub-networks 2-9a to 2-9b (the radio cells 2-6a to 2-6a).
Moving to b), the inter-network interface 2
-8b issues a connection request for the connection 5-5 to the database 2-4b, and the database 2-4b notifies the fixed terminal of the start of movement of the partner terminal. The fixed terminal that has received this notification stops information transmission or transmits only information that may be delayed until it receives the other terminal movement completion notification.

When the new connection 5-5 can be connected, the database 2-4b notifies the inter-network interface unit 2-8t on the fixed terminal side of the completion of the movement of the partner terminal, and transmits information between the fixed terminal and the mobile terminal. Is resumed. If the new connection 4-5 cannot be connected, the connection is disconnected. According to the above method, even if the mobile terminal moves, network resources can always be used effectively. Further, in the above method, the connection switching only needs to be performed up to the database closest to the mobile terminal, so that the connection switching time is further reduced as compared with the second embodiment.

Although the embodiment has been described above, the following modifications are also conceivable. In the embodiment, the example has been disclosed in which the inter-network interface unit after moving issues a connection request for a new connection to the inter-network interface unit on the partner terminal side or the database through which the connection passes. If there is an ATM transfer device through which a connection must pass, or if it is found that a particular transfer device will follow the same route after re-establishing a new connection, the transfer device Then, a connection request for a new connection may be issued.

The inter-network interface unit is not always an essential component, and a radio base station may be connected to the ATM transfer device, and the control device of the ATM transfer device may execute the connection switching process of the present invention. In the third and fourth embodiments, the control unit of the ATM transfer device to which the database is connected controls the database at the same time, or processes a connection connection request to the mobile terminal, and the connection is established in the database. Instead of passing through an ATM transfer device to which the database is connected.

[0033]

As described above, in the first invention, the inter-network interface unit on the mobile terminal side issues a connection request for a connection after movement to any device on the virtual path, and connects the connection. Therefore, without increasing the number of passing ATM cell transfer devices,
There is an effect that network resources can be saved.

In the second aspect of the present invention, the inter-network interface unit on the mobile terminal side issues a connection request for the connection after the movement to the inter-network interface unit on the other side to establish a new connection. This has the effect of minimizing the number of cell transfer devices.

In the third invention, the database relays the connection between the terminals, and after the mobile terminal moves between the sub-networks, the inter-network interface unit on the mobile terminal side issues a connection request for a new connection after the movement. Since the connection is made to the database and the connection is established, the number of ATM cell transfer devices passing therethrough is reduced to save network resources. Further, according to the second invention, the ATM cell required for setup at the time of connection switching (reconnection) is provided. There is an effect that the number of transfer devices can be reduced and the switching time can be reduced.

In the fourth invention, the connection between the terminals is relayed by the database closest to the mobile terminal, and after the mobile terminal moves between the sub-networks, the inter-network interface unit on the mobile terminal side moves to a new network. By issuing a connection request for connection to the database and performing connection connection, the number of ATM cell transfer devices passing through is reduced, thereby saving network resources.
Further, according to the third aspect of the invention, there is an effect that the number of ATM cell transfer devices required for setup at the time of connection switching (reconnection) can be reduced, and the switching time can be shortened.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining a connection operation according to a first embodiment.

FIG. 2 is a block diagram showing a configuration of a conventional ATM mobile communication network.

FIG. 3 is an explanatory diagram illustrating an example of a table that stores the presence of a mobile terminal.

FIG. 4 is a block diagram showing a basic configuration of a communication network to which the present invention is applied.

FIG. 5 is an explanatory diagram for explaining a connection operation according to the second embodiment.

FIG. 6 is an explanatory diagram for explaining a connection operation according to a third embodiment.

FIG. 7 is an explanatory diagram illustrating a procedure of connection connection.

FIG. 8 is an explanatory diagram illustrating a procedure of connection connection.

FIG. 9 is an explanatory diagram showing an operation procedure of the first embodiment.

FIG. 10 is an explanatory diagram showing an operation procedure of the second embodiment.

FIG. 11 is an explanatory diagram showing an operation procedure of the third embodiment.

[Explanation of symbols]

2-1 ... ATM communication network, 2-2 ... ATM cell transfer device,
2-3 line, 2-4 database, 2-5 radio base station, 2-6 radio cell, 2-7 mobile terminal, 2-8
Inter-network interface unit, 2-9 ... subnetwork, 2-10 ... fixed terminal, 3-3, 3-4
…connection

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yoneo Watanabe 1-32 Shinrashima-cho, Kanagawa-ku, Kanagawa-ku, Kanagawa-ku, Japan WIP Co., Ltd. Mobile Communication Technology Laboratory (72) Inventor Masaya Nishio Kanagawa, Japan 1-32 Shinrashima-cho, Kanagawa-ku, Yokohama-shi WRP Corporation Mobile Communication Technology Laboratory (56) References JP-A-6-77989 (JP, A) JP-A-9-8827 (JP, A) JP-A-8-186580 (JP, A) JP-A-1-154635 (JP, A) JP-A-3-214889 (JP, A) JP-A 8-265844 (JP, A) JP-A-3 175750 (JP, A) JP-A-6-30460 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04L 12/28 H04Q 7/22

Claims (2)

(57) [Claims] A plurality of ATM cell transfer devices are connected by a line, an inter-network interface unit is connected to the ATM cell transfer device, and a radio base station for performing radio communication with a mobile terminal is provided below the inter-network interface unit. Connected, and further, a database for registering location information of the mobile terminal is connected to any of the ATM cell transfer devices, and the mobile terminal communicates between the sub-networks which are the total area of the radio base stations managed by the inter-network interface unit. in mobile communication network position information of the database is updated each time the move, when the fixed terminal communicates with the mobile terminal by calling, the
The ATM cell transfer device to which the fixed terminal belongs and the database
Connection between ATM cell transfer devices to which the source is connected
ATM cell transfer to which the database is connected
Transmitting device and the network corresponding to the location of the mobile terminal.
Through the connection of the interface unit between workpieces
The fixed terminal and the mobile terminal are connected to each other, and when the mobile terminal moves between the sub-networks, a network corresponding to the destination sub-network
Interface unit connects to the database
New connection for continued ATM cell transfer equipment
A connection request is issued, and the AT to which the database is connected
M-cell transfer device and network between the mobile terminal side
A mobile communication network, wherein a connection between interface units is set . 2. A plurality of ATM cell transfer devices are connected by a line, an inter-network interface unit is connected to the ATM cell transfer device, and a radio base station for performing radio communication with a mobile terminal is provided below the inter-network interface unit. Connected to each other, and a plurality of databases for registering the location information of the mobile terminals are each connected to one of the ATs.
In a mobile communication network connected to an M-cell transfer device, the location information of the database is updated every time a mobile terminal moves between sub-networks, which is the total area of radio base stations managed by the inter-network interface unit. , when the fixed terminal communicates with the mobile terminal by calling, the
The fixed terminal and the database closest to the mobile terminal are connected
Connection between the established ATM cell transfer devices , and
AT to which the database closest to the mobile terminal is connected
M cell transfer device and the location corresponding to the location of the mobile terminal.
Network interface unit connection
Connecting the fixed terminal and the mobile terminal via the network , and when the mobile terminal moves between the sub-networks, a network corresponding to the destination sub-network.
Interworking interface unit is the most
For ATM cell transfer equipment with a close database connected
And issues a new connection connection request to the mobile terminal.
Cell transfer equipment connected to the database closest to
Interface between the mobile device and the mobile terminal
A mobile communication network wherein a connection between units is set .