JPH11161618A - Mobile computer management device, mobile computer device, and mobile computer registration method - Google Patents

Abstract

(57) [Problem] To enable a mobile computer to authenticate a user operating a mobile computer when the mobile computer transmits a registration message of a current location from a destination network to a mobile computer management device (home agent). To provide a mobile computer management device. SOLUTION: A mobile computer management device which is installed in a home network of the mobile computer and enables the mobile computer to move between networks and communicate with each other, based on a registration message transmitted from the mobile computer, the current status of the mobile computer. A registration function for registering location information, and prior to execution of registration by the registration function, the validity of the user of the mobile computer is checked using information based on a user input received from the mobile computer, and the check result is obtained. A user authentication function for controlling execution of registration of the information of the current position by the registration function based on the registration function; and transferring a packet addressed to the mobile computer to the current position of the mobile computer based on the information registered by the registration function. It has a transfer function.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system comprising a plurality of computers for mutually exchanging data between a plurality of interconnected networks and providing necessary services, and moving between networks for communication. The present invention relates to a mobile computer device capable of performing a mobile computer, a mobile computer management device for managing mobile location information of the mobile computer, and transferring a packet addressed to the mobile computer to a current location of the mobile computer, and a mobile computer registration method.

[0002]

2. Description of the Related Art The use of computer systems has expanded rapidly and widely in various fields as computer systems have become smaller, lower in price, and network environments have been enriched, and there has been a shift from centralized systems to distributed systems. Is progressing. In particular, in recent years, in addition to the progress and spread of computer network technology in addition to the advancement and enhancement of computer systems, not only sharing of resources such as files and printers within the office, but also communication outside the office and outside the organization (e-mail , E-news, file transfer, etc.), and these have begun to be widely used. In particular, in recent years, the use of the world's largest computer network "Internet" has become widespread. External users who connect to the Internet and use published information and services, or conversely, access the Internet through the Internet On the other hand, by providing information and services, a new computer business has been developed. New technologies are being developed and deployed for the use of the Internet.

[0003] In addition, with the spread of such networks, technical development for mobile communication has been performed. In mobile communication, a user having a portable terminal and a computer moves and communicates on a network. In some cases, the position on the network is changed while performing communication, and a method for managing the address of the mobile computer, which changes in such communication, on the network and correctly reaching the communication content is required.

In general, when performing mobile communication, a router (home agent) for managing the destination data of the mobile computer is placed in the network to which the mobile computer belongs, and when the mobile computer moves, the home agent is Send a registration message indicating the location. When the registration message is received, transmission of data addressed to the mobile computer is performed by encapsulating an IP packet addressed to the original address of the mobile computer in a packet addressed to the current location address of the mobile computer via the home agent. Of the data is controlled. For example, in FIG. 1, the mobile computer 2 originally belonging to the home network 1a
Moves to another network 1b, and the network 1c
When communicating with another computer (CH) 3 in the
The home agent (HA) 5 performs the above role for the mobile computer 2. This system is a system called Mobile IP, which is being standardized by the IETF mobile-IP working group, which is an Internet standardization organization (literature: RFC2002, IP mobile).
city support (C. Perkins)).

In the mobile IP system, when the mobile computer moves to a new destination, it is necessary to send a registration message of the current location to the home agent. In order to avoid an attack such as impersonation on the mobile computer, an authentication code is added to the location registration message according to security information exchanged in advance between the mobile computer and the home agent. If the registration message is not a registration message to which a correct authentication code is added, the location registration of the mobile computer is not performed.

However, the security measures specified by the mobile IP are security for each host (mobile computer), and do not authenticate the entity of the user using the mobile computer. That is, for example, if the host itself is stolen by an unauthorized user while security information for authentication between the hosts is held in the mobile computer, the unauthorized user becomes a legitimate user and retrieves information on the home network. Can be very dangerous.

Further, even if the host is not stolen, confidential information on the home network may be taken out only by temporarily borrowing the mobile computer for which the authorized user has performed the registration process.

[0008] That is, the security measures in the conventional mobile IP system can cope with impersonation on a host basis, but can be said to be extremely weak against attacks in which an unauthorized user impersonates a legitimate user. For this reason, there is a possibility that confidential information of the internal network may be extracted to the destination (external network).

[0009]

Although the conventional security measures in the mobile IP system correspond to the impersonation of each host, it can be said that they are extremely weak against an attack in which an unauthorized user impersonates a legitimate user. for that reason,
There is a possibility that confidential information of the internal network may be taken out to the destination (external network).

[0010] The present invention has been made in view of the above circumstances, and when a mobile computer connects to a destination network and transmits a registration message of a current location to a home agent, a user operating the mobile computer. It is an object of the present invention to provide a mobile computer management device, a mobile computer device, and a mobile computer registration method that can authenticate a user.

[0011] The present invention also copes with the case where a mobile computer once sends a registration message of the current location to a home agent, periodically performs user authentication, and uses a mobile computer by an unauthorized user after a session is established. It is an object of the present invention to provide a mobile computer management device, a mobile computer device, and a mobile computer registration method that can be performed.

[0012]

Means for Solving the Problems The present invention (claim 1) provides:
A mobile computer management device (home agent) installed in a home network of a mobile computer and enabling the mobile computer to move between networks and perform communication, based on a registration message transmitted from the mobile computer. Registration means for registering information on the current position of the mobile computer, and prior to execution of registration by the registration means,
Using the information based on the user input received from the mobile computer, the validity of the user of the mobile computer is checked, and based on the check result, execution of registration of the information on the current position by the registration unit is controlled. And a transfer means for transferring a packet addressed to the mobile computer to a current location of the mobile computer based on the information registered by the registration means.

Preferably, prior to execution of registration by the registration means, the validity of the mobile computer is checked based on a registration message received from the mobile computer, and both the mobile computer and a user of the mobile computer are checked. The apparatus may further include a host authentication unit that controls to permit execution of registration of the information on the current position by the registration unit when the validity is confirmed.

Preferably, when a new registration message is received from the mobile computer, a return request message for requesting the mobile computer to return information for user authentication prior to execution of registration by the registration means. The user authentication unit further includes a transmission unit that transmits the information based on a user input to the mobile computer as information for the user authentication returned from the mobile computer in response to the return request message. The legitimacy of the user may be checked using information based on the user in the written response message.

[0015] Preferably, when the transmitting means receives a registration message for re-registering the same current position from the mobile computer, it is indicated that the user authentication should be performed again under a predetermined condition. In this case, the return request message may be transmitted again to the mobile computer before re-registration is executed by the registration unit.

[0016] Preferably, the registration message for re-registration is received at a predetermined interval, and the condition predetermined in the transmitting means is that the return request message is transmitted at an interval longer than the predetermined interval. May be determined to be transmitted.

The predetermined conditions include, for example, that a predetermined time has elapsed since the last time user authentication was performed, or that re-registration was performed when the user authentication was previously performed. For example, the number of times this reception may be performed a predetermined number of times after the registration message is received may be used. Note that the user authentication may be performed every time a registration message for performing re-registration is received.

Preferably, for the same mobile computer, if the validity of the user has not been confirmed from the returned response message for a predetermined number of consecutive times, the mobile computer will not be able to use the mobile computer thereafter. The registration request from the computer may be rejected.

Preferably, the message requesting user authentication includes a challenge code, and checks the one-time password based on the challenge code returned from the mobile computer as information based on the user input, thereby verifying the validity of the user. Sex may be determined.

Preferably, the legitimacy of the user may be determined based on whether or not the password returned from the mobile computer as information based on the user input matches a password registered in advance.

The present invention (Claim 9) is a mobile computer device capable of performing communication by moving between mutually connected networks, wherein the mobile computer device is provided from a destination outside its own home network. Installed on the home network,
Transmitting means for transmitting a registration message including information on the current position to a mobile computer management device (home agent) having means for transferring a packet addressed to the own device to the current position of the own device, and user input for user authentication Receiving means for receiving, and returned from the mobile computer management device that has received the registration message, when receiving a return request message requesting the return of information for user authentication,
Returning means for returning a response message, in which the information based on the user input is written as the information for user authentication, to the mobile computer management device.

Preferably, the mobile computer management device further comprises means for judging the validity of the mobile computer management device based on the return request message received from the mobile computer management device. If it is determined that the response message is correct, the response message including information based on the user input may be returned.

Preferably, in a case where a message indicating that the validity of the user has not been transmitted from the mobile computer management apparatus in response to the returned response message has been transmitted continuously for a predetermined number of times, May suppress transmission of a registration request message from the own device thereafter.

According to the present invention (claim 12), the mobile computer
A mobile computer management device (home agent) that manages the current location information of the mobile computer and transfers a packet addressed to the mobile computer to the current location of the mobile computer so that the mobile computer can perform communication by moving between networks. On the other hand, a mobile computer registration method for registering, wherein the mobile computer is, when connected to a destination outside the home network of the own device, addressed to the mobile computer management device installed in the home network. The mobile computer management device transmits a registration message including information on the current position, and uses the information based on the user input transmitted from the mobile computer to check the legitimacy of the user of the mobile computer. When it is determined that the mobile computer is valid, the current position of the mobile computer is registered.

The present invention (claim 13) provides a method for registering a mobile computer in a mobile computer management device (home agent) which is installed in a home network of a mobile computer and enables the mobile computer to move between networks and perform communication. When registering information on the current position of the mobile computer based on a registration message transmitted from the mobile computer, prior to performing the registration, using information based on a user input received from the mobile computer It checks the validity of the user of the mobile computer, controls the execution of registration of the information on the current position based on the check result, and, based on the information on the registration, transmits a packet addressed to the mobile computer to the mobile computer. Is transferred to the current position.

The present invention (claim 14) relates to a mobile computer registration method for a mobile computer device capable of performing communication by moving between mutually connected networks, wherein the mobile computer registration method is provided outside the home network of the own device. A registration message including the current location information is transmitted from the destination to a mobile computer management device (home agent) having means for transferring a packet addressed to the own device to the current location of the own device, which is installed in the home network. When receiving a return request message returned from the mobile computer management device that has received the registration message and requesting the return of information for user authentication, the information based on the user input is used as the information for user authentication. A response message written as a response message is returned to the mobile computer management device.

Note that the above-described invention relating to the apparatus is also valid as an invention relating to a method, and the invention relating to the method is also valid as an invention relating to an apparatus. Further, the above-described invention is also realized as a machine-readable medium storing a program for causing a computer to execute a corresponding procedure or means.

Although the conventional security measures in the mobile IP system deal with impersonation on a host-by-host basis, they can be said to be extremely weak against attacks in which an unauthorized user impersonates a legitimate user. For this reason, there is a possibility that confidential information of the internal network may be extracted to the destination (external network).

According to the present invention, when the mobile computer connects to the destination network and transmits a registration message of the current location to the mobile computer management device (home agent),
Since the mobile computer and the mobile computer management device exchange information that cannot be known unless the user is a registered valid user, the user operating the mobile computer can be authenticated, and the mobile computer can be more safely protected. Can be operated.

According to the present invention, user authentication is periodically performed even after the mobile computer once sends the current location registration message to the mobile computer management device (home agent). It can also respond to the case of using. Further, if the unauthorized user has failed the authentication more than a certain number of times, subsequent registration can be disabled. As a result, unauthorized operation due to theft of the mobile computer or impersonation of the user can be prevented.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a basic configuration of a communication system according to the present embodiment. It is assumed that the communication system of FIG. 1 supports communication of a mobile computer by a mobile IP (RFC2002). In the mobile IP protocol, a mode that assumes the existence of a router called a foreign agent that performs packet delivery to a mobile computer in a destination network and a mode in which a foreign agent is not provided (the mobile computer itself also serves as a foreign agent) are used. of a
There is an address mode, but in the present embodiment, the latter will be described as being adopted.

In FIG. 1, the home network 1a, the first network
The other department network 1b and the second other department network 1c are interconnected via the Internet 6, and the mobile computer (MN) 2 and the communication partner (C
H) 3 are connected to these networks or to the Internet 6 as external nodes.

In the present embodiment, a case will be described in which the mobile computer 2 having the home position inside the network 1a has moved to the other department network 1b. The home network 1a is provided with a home agent (HA) 5 that manages information on the current location where the mobile computer has moved to support the mobile IP protocol. The number of mobile computers to be managed is arbitrary. As described above, the IP packet transferred to the moving mobile computer 2 passes through the home agent 5 and transfers the IP packet addressed to the original address of the mobile computer 2 (the address in the home network 1a) to the mobile IP. By encapsulating the packet in a packet addressed to the current position address in the format, data path control for the mobile computer 2 can be performed.

When the mobile computer 2 moves out of the home network, the mobile computer 2 acquires an address to be used in the destination network by a protocol such as DHCP or PPP in the destination network (1b in this case). . After acquiring the address, mobile computer 2
Transmits a registration message including information on the current location to the home agent 5 of the home network 1a.

FIG. 2 shows a format of a registration message transmitted from the mobile computer 2 to the home agent 5. The flag (FLAG) indicates the operation mode (encapsulation method, etc.) of the mobile IP.

Lifetime indicates the expiration date of this registration. When the expiration date has passed, the mobile computer 2 has to transmit a registration message to the home agent 5 again to perform re-registration.

Home Address indicates the home position of the mobile computer, Care-of Address indicates the current position of the mobile computer, and Home Agent indicates the address of the home agent 5.

Identification is an ID for registration and is added to prevent a replay attack.
Extensions include at least authentication information (for host authentication) between the mobile computer 2 and the home agent 5. This Extension part is shown in FIG. SPI indicates a security parameter index exchanged between the two, and Authenticator indicates an authentication code.

When this registration message is received by the home agent 5 and the registration processing is correctly performed, a registration response message shown in FIG. 4 is returned to the mobile computer 2. co
In de, a response code 0 or 1 indicating successful registration is described. On the other hand, if the registration fails, a registration response message in the same format as in FIG. 4 is returned to the mobile computer 2. In this case, response codes indicating various reasons for registration failure are described.

The response code (Reply code)
es). The number on the left is a code, and the description on the right is the meaning indicated by the code. <Success Case> 0: Registration acceptance (registration accept)
ted) 1: Registration is accepted, but simultaneous movement binding is not supported (registration accepted, bu
t simultaneous mobile b
indices unsupported) <failur for foreign agent
e for Foreign agent> 64: reason unspecified
d) 65: prohibited for administrative reasons (administrati)
very prohibited 66: Insufficient resources
resources 67: Mobile node authentication failure (mobile node)
failed authentication 68: Home agent failed authentication (home a
gent failed authenticated
n) 69: Requested Lifeme is too long (req
used Lifetime too long 70: The request format is incorrect (poorly for
med Request) 71: Response format is incorrect (poorly for)
Med Reply 72: Request encapsulation not available (requests)
ted encapsulation unvail
able) 73: Requested Van Jacobson compression not available (requested Van Jacobson)
compression unavailable 80: Home network is unreachable (ICMP error received) (home network unreachable)
ble (ICMP error received) 81: Home agent host is unreachable (ICM
P error reception) (home agent host u
nreachable (ICMP error release
82): Home agent port is unreachable (ICM
P error reception) (home agent port u
nreachable (ICMP error release
iv)) 88: Home agent unreachable (ICMP error received) (home agent unreachable)
e (ICMP error received)) <failure for home agent
case of for home agent> 128: reason unknown (reason unspecified)
ed) 129: Prohibited for administrative reasons (administrate)
immediately prohibited 130: Insufficient resources
resources 131: Authentication failure of mobile node (mobile node)
e failed authentication 132: Foreign agent failed authentication (for
eign agentfailed authorente
133): Registration identifier does not match (registra)
Tion Identification Mismat
ch) 134: Request format is incorrect (poorly fo)
rmed Request) 135: The number of simultaneous movement binds is too large (too ma)
ny simultaneous mobility
bindings 136: unknown home agent address (unk)
Now, in the present embodiment, even if the home agent 5 receives the registration message from the mobile computer 2, the home agent 5 does not immediately perform the registration process, authenticates the user of the mobile computer 2, and succeeds in the user authentication. The registration process is performed only when the registration is performed.

In the following, an example in which the home agent 5 exchanges messages by challenge-response in order to authenticate the user using the mobile computer 2 is shown in FIG.
This will be described with reference to FIG.

FIG. 6A shows the format of the challenge message.
FIG. 6B shows the format of the response message.
In this example, when the mobile computer 2 sends a registration request message to the home agent 5, the home agent 5
First checks the authentication information and performs host authentication. And
If the host authentication is successful, home agent 5
Sends a challenge message to the mobile computer 2 requesting a password input.

Upon receiving the challenge message, the mobile computer 2 prompts the user to enter a password by displaying the message or the like. When the password is input, the home agent 5 sends a response message in which the password input by the user is written.

The home agent 5 having received the response message compares the password registered in advance with the mobile computer at the time of residence in the home network, and as a result of the comparison, the password returned from the mobile computer is correct. If it is confirmed that the registration is successful, the registration of the current position is permitted, and a registration response message including a response code indicating the success of the registration is returned. Start the transfer.

By performing the password authentication on the home agent 5 side in this way, it becomes unnecessary to carry information for user authentication in the mobile computer and carry it, thereby avoiding the danger of the mobile computer being stolen. be able to. In addition, since the administrator of the entire system can also centrally manage the use password of the computer being moved on the home agent 5, it is easy to cope with abnormal situations such as unauthorized use of the computer, and more secure. System operation can be enabled.

Further, the home agent verifies whether the host that transmitted the registration message of the mobile IP is a legitimate host, and verifies whether the user who intends to perform the mobile IP communication is a legitimate user. Can be operated independently, so that mobile IP communication can be permitted to any combination of a user and a host (mobile computer). That is, for example, in a system where user authentication is performed between the host and the user instead of the home agent and host authentication is performed between the host and the home agent, authentication cannot be performed unless the combination of the host and the user is fixed. On the other hand, more flexible management becomes possible.

For the subsequent re-registration message, various methods such as a method of performing user authentication each time in the same procedure, a method of performing user authentication only once and several times, and a method of not performing user authentication are considered. .

In the above description, the password is returned from the mobile computer to the home agent 5, but a set of the password and the user ID is returned, and the home agent 5 checks whether or not this set has been registered beforehand to confirm the validity of the user. Sex may be determined.

In the above description, first, host authentication is performed in response to a registration request from the mobile computer to the home agent.
Although the example of performing the user authentication procedure again after the message prompting the transmission of the password is returned from the home agent to the mobile computer has been described, by transmitting the first registration request including the password when the mobile computer transmits the first registration request, It is also possible to perform host authentication and user authentication in one step.

However, the steps of host authentication by registration request and user authentication by password transmission are separated,
Alternatively, it is also possible to perform management based on stronger security by sending a user name and a password twice at the time of user authentication. In the latter case, for example,
The home agent 5 sends the user name first and returns a one-time password challenge message based on the initial data registered for each user in advance.
On the other hand, a method is adopted in which a formal registration is performed when the user returns a response message again. In the former case, the mobile computer that has received the reply message from the home agent in response to the registration request can send the user authentication information (password) after verifying whether the communication partner is a valid home agent. .

As described above, the registration request and the user authentication information are
Process as a set, or enter a user name and password
Whether to process as a set or to treat them as separate messages should be determined according to the requirements for the security of the system and the requirements for the user interface on the mobile computer side.

In the above example, an example of user authentication by simple password collation has been described, but other methods can be used for user authentication. For example, a method of performing authentication using a one-time password can be considered. Hereinafter, an example of user authentication using a one-time password will be described with reference to FIG.

FIG. 8A shows the format of the challenge message.
FIG. 8B shows the format of the response message.
In this example, when the mobile computer 2 sends a registration request message to the home agent 5, the home agent 5 first checks the authentication information and performs host authentication. And
If the host authentication is successful, a challenge code of a one-time password is obtained based on the registration information of the user who uses the mobile computer 2. Then, the mobile terminal 2 returns a challenge message to which the challenge code is added and requesting the input of the password.

The mobile computer 2 having received the challenge message uses another utility to reflect the one-time password challenge code in the challenge message and the password entered by the user.
Data responding to the challenge is calculated, and a response message including the data is transmitted to the home agent 5.

The home agent 5 having received the response message performs the same calculation as that performed by the mobile computer 2 based on the registration information, and performs data collation.
If the registration is correct, the registration of the current position is permitted, and a registration response message including a response code indicating successful registration is returned, and the transfer of the data packet to the mobile computer 2 is started by registering the current position.

For the subsequent re-registration message, various methods such as a method of performing user authentication each time in the same procedure, a method of performing user authentication only once and several times, and a method of not performing user authentication are considered. .

When the user authentication fails in each of the above examples, a registration response message including a code indicating the user authentication failure may be immediately returned to the mobile computer. Alternatively, if the user authentication is not successful even after the exchange of the challenge message and the response message has been repeated a prescribed number of times, a registration response message including a code indicating the user authentication failure may be returned to the mobile computer.

In the above two examples, the user authentication at the time when the mobile computer 2 connects to the destination network and starts the registration process has been described. However, in actual operation, an unauthorized user connects the mobile computer 2 after the registration is completed. It is desirable to cope with a case where information in the home network is leaked by unauthorized use (for example, a legitimate user leaves his / her desk with the mobile computer 2 connected, and is used by an unauthorized user during that time).

As a corresponding process for this, the mobile computer 2
It is conceivable that the home agent 5 transmits a user authentication request message to the mobile computer 2 at regular time intervals even after the registration process has succeeded once. FIG. 9 shows such an example.
This will be described with reference to FIG. FIG. 9 is an example of a block diagram showing a function added to the home agent 5 in this case, and FIG. 10 is an example of the procedure.

In the home agent 5 having the function shown in FIG. 9, the re-user authentication interval time designated by the user (or the system administrator) is input to the register 51 in advance.

When the user authentication sequence is executed for a certain mobile computer 2 (step S15), the timer counter 52 corresponding to the mobile computer 2 is cleared to 0 (step S11). Note that the first user authentication sequence is, for example, when a mobile computer receives the first registration message after moving, as shown in FIGS.

Thereafter, each time a re-registration message of the current position is received from the mobile computer and the re-registration is performed, the corresponding timer counter 52 is updated to the elapsed time (step S1).
2 to S14).

At the time of this position re-registration, the interval time of the register 51 and the value of the corresponding timer counter 52 are compared by the comparator 53 (step S14). If the content of the timer counter 52 is smaller than the interval time,
It re-registers the current location and sends a registration success message without user authentication.

On the other hand, when the content of the timer counter 52 reaches the interval time, the user authentication sequence as shown in FIGS. 5 and 7 is executed again (step S).
15). When the user authentication is correctly performed, re-registration of the current position is permitted, a registration response message including a response code indicating successful registration is returned, and the re-registration of the current position is performed to transmit a data packet to the mobile computer 2. The transfer is continued, and the corresponding timer counter 52 is set to 0 again.
Is cleared (step S11).

A series of procedures such as repetition of location re-registration without user authentication and updating of the timer counter, user authentication after a lapse of a predetermined time, and location re-registration when succeeded, are now performed. This is repeated until the expiration date of the location elapses or the user authentication fails or the location registration fails.

If the user authentication fails,
As described above, the registration response message including the code indicating the user authentication failure may be immediately returned to the mobile computer, or even if the exchange of the challenge message and the response message is repeated a specified number of times, the user authentication does not succeed. In such a case, a registration response message including a code indicating the failure of the user authentication may be returned to the mobile computer.

In the above description, an example in which user authentication is performed every fixed time has been described. However, a method of performing user authentication each time a re-registration message is received, a method of performing user authentication only once in several times, and the like. Various methods are conceivable.

In the case where the mobile computer 2 is stolen and an unauthorized user attempts to make a registration request from outside the home network, for example, if the user authentication as illustrated in FIGS. In this method, it is extremely difficult to succeed in user authentication), the current position cannot be registered, and unauthorized use cannot be performed. However, by repeatedly sending and receiving registration (user authentication) messages, such as by an unauthorized user trying to break a password brute force,
There is a risk that normal operation cannot be performed due to congestion of home network traffic. Further, there is a possibility that an unauthorized user may be subjected to a password analogy attack using a dictionary or the like.

To cope with these problems, if the user authentication fails a certain number of times, the mobile computer 2
It is conceivable that the sending of a message from is impossible. Such an example will be described with reference to FIGS. FIG. 11 is an example of a block diagram showing functions added to the mobile computer 2 in this case, and FIG. 12 is an example of the procedure.

In the mobile computer 2 having the function shown in FIG. 11, the number of consecutive user authentication failures designated by a user (a system administrator or a user of the mobile computer) is input to the register 121 in advance (step S21).

Each time the mobile computer 2 receives from the home agent 5 a message indicating that user authentication has failed,
The failure counter 122 (preliminarily initialized) is incremented (steps S22 to S25). on the other hand,
If the user authentication is successful (Yes in step S23), the failure counter 122 is reset to zero.

In step S25, the register 123 and the authentication failure counter 1
22 are compared and if they match (step S
In the case of “Yes” at 25), the mobile computer 2 activates the message transmission stop control unit 124 and stops any message transmission thereafter (step S26). In order to release the message transmission suspension by the message transmission suspension control unit 124, it is necessary to use information stored in the home agent unique to the mobile computer 2.

In the above description, the message transmission suppression function is provided in the mobile computer. However, as another example (FIGS. 13 and 14), the home agent 5 side has a user authentication failure counter 1
52, and if the value of the failure count register 151 is the same as this, it is also conceivable that the registration will not succeed even if any message is transmitted thereafter.

In this case, the home agent 5 having the function shown in FIG.
Is input to the register 151 corresponding to each mobile computer (step S3).
1).

The home agent 5 increments the corresponding (initialized) failure counter 152 every time the user authentication is not successful (steps S23 to S25). On the other hand, if the user authentication succeeds (Yes in step S33), the failure counter 152 is reset to 0.

In step S35, the register 151 and the authentication failure counter 1
52, and if they match (step S
In the case of “Yes” at 35), the home agent 5 activates the registration message reception rejection control unit 154, and rejects any subsequent reception of the registration message from the mobile computer 2 (step S26).

Although this method cannot prevent the exchange of unnecessary messages, it is considered that the security standard is somewhat looser than the examples in FIGS. 11 and 12, but the method shown in FIG. And which method of FIG. 13 should be used.

In addition to the above two examples, the failure of the specified number of times is detected by the mobile computer 2, and this is detected by the mobile computer 2.
, The home agent 5 may notify the home agent 5, and the home agent 5 may refuse to accept any registration message from the mobile computer 2 thereafter.

In the above three examples, the registration of the mobile computer 2 may be deleted when a specified number of authentication failures are detected, or the transfer may be supported until the expiration date.

Next, the configuration of the home agent 5 according to the present embodiment will be described. FIG. 15 shows a block diagram of a configuration example of a main part of the home agent 5. As shown in FIG. 15, the home agent 5 includes a mobile registration processing unit 201 that performs processing related to mobile registration, a communication processing unit 203 that performs processing other than mobile registration, and a data input / output that performs data input / output processing to a network. It has a unit 202.

The mobile registration processing unit 201 includes a user authentication database 211 for registering data necessary for authentication such as a password, a challenge generation unit 212 for performing processing for generating a challenge message to be transmitted to the mobile computer, A password extracting unit 213 for extracting a password from the transfer registration message, a user information extracting unit 214 for extracting user information from the transfer registration message, and a registration for performing a process for generating a registration response message. It has a response generation unit 215.

For example, in the case of the example of the authentication procedure shown in FIG. 5, a registration request message transmitted from the mobile computer 2 is first transmitted from the data input unit 202 to the mobile registration processing unit 201 via the network. Then, host authentication is performed by the user information extraction unit 214 of the movement registration processing unit 201 based on the registration request message and the contents of the user authentication database 211. If the host authentication is successful, the password is input by the challenge generation unit 212. Is generated and returned to the mobile computer 2 via the data input / output unit 202.

Here, as described above, the mobile computer 2
Upon receiving the challenge message, the user is prompted to enter a password by displaying a message or the like. Then, if the password is input, a response message in which the password input by this user is written is
Send to home agent 5.

The response message transmitted from the mobile computer 2 is as follows. The information is transmitted from the data input unit 202 to the movement registration processing unit 201 via the network. Then, the password extraction unit 213 of the mobile registration processing unit 201 performs user authentication based on the response message and the contents of the user authentication database 211. If the user authentication is successful, the registration response generation unit 215 determines that the registration was successful. A registration response message including the response code is generated, and the registration response message is returned to the mobile computer 2 via the data input / output unit 202. At the same time, the current position of the mobile computer is registered, and the transfer of the data packet to the mobile computer is started.

Other authentication procedures described so far can be executed by the transfer registration processing unit 201. of course,
The home agent 5 can be entirely or partially realized by a program.

The security measures in the conventional mobile IP system can cope with impersonation on a host basis, but can be said to be extremely weak against an attack in which an unauthorized user impersonates a legitimate user. For this reason, there is a possibility that confidential information of the internal network may be extracted to the destination (external network).

According to the present embodiment, when the mobile computer connects to the destination network and sends a registration message of the current position to the home agent, the registered valid user between the mobile computer and the home agent. Since information that cannot be known otherwise is exchanged, the user operating the mobile computer can be authenticated, and the mobile computer can be operated more safely.

Further, according to the present embodiment, even after the mobile computer once sends the current location registration message to the home agent, user authentication is periodically performed, and after a session is established, an unauthorized user may use the mobile computer. Can also respond. Further, when the unauthorized user has failed the authentication for a fixed number of times, the transmission of the registration message thereafter can be stopped or the acceptance of the registration message can be prohibited.

As a result, it is possible to prevent unauthorized operation due to theft of the mobile computer or impersonation of the user. In the present embodiment,
Colocated Care-of Address
Although the communication system based on the mode has been described, the present invention is also applicable to a mobile communication system assuming the existence of a foreign agent.

The present invention is applicable not only to the mobile IP described in RFC2002 but also to various other mobile communication protocols. Further, in addition to the above functions, for example, the processing part, a setting counter for specifying the number of re-registrations at which the mobile computer performs user authentication, a counter for counting the number of registrations, and the like can be realized as hardware or software. Further, the present invention can be embodied as a machine-readable medium storing a program for causing a computer to execute the above-described procedures or means. The present invention is not limited to the above-described embodiment, and can be implemented with various modifications within the technical scope.

[0091]

According to the present invention, when a registration message of the current location is transmitted from a mobile computer connected to a destination network to the mobile computer management device, the registration between the mobile computer and the mobile computer management device is performed. Since information that cannot be known unless the user is a valid user is exchanged, the user operating the mobile computer can be authenticated. As a result, unauthorized operation due to the theft of the mobile computer or impersonation of the user can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of a network according to an embodiment of the present invention.

FIG. 2 is a view showing a registration request message format transmitted by the mobile computer according to the embodiment;

FIG. 3 is an exemplary view showing an extended registration request message for host authentication transmitted by the mobile computer according to the embodiment;

FIG. 4 is an exemplary view showing a registration request response message from the home agent according to the embodiment;

FIG. 5 is an exemplary view for explaining a user authentication method according to the embodiment;

FIG. 6 is a diagram showing an example of a message format for user authentication.

FIG. 7 is an exemplary view for explaining another user authentication method according to the embodiment;

FIG. 8 is a diagram showing another example of a message format for user authentication.

FIG. 9 is a diagram showing a configuration of a home router that performs user authentication accompanying location re-registration.

FIG. 10 is a flowchart showing an operation procedure of the home router of FIG. 9;

FIG. 11 is a diagram showing a configuration of a mobile computer that addresses attacks related to user authentication.

FIG. 12 is a flowchart showing an operation procedure of the mobile computer of FIG. 11;

FIG. 13 is a diagram showing a configuration of a home router that addresses attacks related to user authentication.

FIG. 14 is a flowchart showing an operation procedure of the home agent of FIG. 11;

FIG. 15 is an exemplary view showing a configuration example of a home agent according to the embodiment;

[Explanation of symbols]

 1a, 1b, 1c Network 2 Mobile computer 3 Communication partner computer 5 Home agent 6 Internet 51 Interval register 52 Timer counter 53 Comparison unit 121 Failure count register 122 Failure counter 123 Comparison unit 124 ... Message transmission stop control unit 151... Failure number register 152. 212: challenge generator 213: password extractor 214: user information extractor 215: registration response generator

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H04L 12/28 H04L 11/20 B 12/66 (72) Inventor Etsuyuki Tsuda 1 Kosuka Toshiba-cho, Saiwai-ku, Kawasaki City, Kanagawa Prefecture Toshiba R & D Center (72) Inventor Toshio Okamoto 1 Toshiba R & D Center, Komukai Toshiba-cho, Kawasaki-shi, Kanagawa

Claims (14)

[Claims] 1. A mobile computer management device which is installed in a home network of a mobile computer and enables the mobile computer to perform communication by moving between networks, based on a registration message transmitted from the mobile computer. Registration means for registering information on the current location of the mobile computer; and prior to execution of the registration by the registration means, using the information based on the user input received from the mobile computer, the validity of the user of the mobile computer. A user authentication unit that controls execution of registration of the information on the current position by the registration unit based on the inspection result; and a packet addressed to the mobile computer based on the information registered by the registration unit. Transfer means for transferring the data to the current location of the mobile computer. 2. Prior to execution of registration by said registration means,
The validity of the mobile computer is checked based on the registration message received from the mobile computer, and if the validity of both the mobile computer and the user of the mobile computer is confirmed, the current position by the registration unit is checked. The mobile computer management device according to claim 1, further comprising a host authentication unit that controls execution of registration of the information. 3. When a new registration message is received from the mobile computer, a return request message for requesting the mobile computer to return information for user authentication is issued prior to execution of registration by the registration means. Transmitting means for transmitting, the user authentication means writes information based on a user input to the mobile computer as information for the user authentication returned from the mobile computer in response to the return request message 2. The mobile computer management device according to claim 1, wherein the validity of the user is checked using information based on the user in the response message obtained. 4. When the transmitting means receives a registration message for re-registering the same current position from the mobile computer, it is indicated that the user authentication should be performed again under a predetermined condition. 4. The mobile computer management device according to claim 3, wherein the return request message is transmitted to the mobile computer again before the re-registration is executed by the registration unit. 5. A registration message for performing the re-registration is received at a predetermined interval, and a condition predetermined in the transmitting means is that the return request message is transmitted at an interval longer than the predetermined interval. The mobile computer management device according to claim 4, wherein transmission is set. 6. If the validity of the user has not been confirmed from the returned response message for the same mobile computer for a predetermined number of consecutive times, then the mobile computer is no longer valid. 6. The mobile computer management device according to claim 4, wherein a registration request from the mobile computer is rejected. 7. The message requesting user authentication includes a challenge code, and checks the one-time password based on the challenge code returned from the mobile computer as information based on the user input, thereby verifying the user's validity. The mobile computer management device according to any one of claims 3 to 5, wherein the determination is made as follows. 8. The validity of a user is determined based on whether or not a password returned from the mobile computer as information based on the user input matches a password registered in advance. The mobile computer management device according to any one of the above. 9. A mobile computer device capable of performing communication by moving between mutually connected networks, wherein the mobile computer device is installed in the home network from a destination outside the home network of the own device. Transmitting means for transmitting a registration message including information on the current position to a mobile computer management device having means for transferring a packet addressed to the own device to the current position of the own device; and receiving means for receiving a user input for user authentication When receiving a return request message requesting the return of information for user authentication, returned from the mobile computer management device that has received the registration message, the information based on the user input is used for the user authentication. Return means for returning a response message written as information to the mobile computer management device. Calculation machine equipment. 10. The mobile computer management apparatus further comprising: means for judging the validity of the mobile computer management apparatus based on the return request message received from the mobile computer management apparatus. The mobile computer device according to claim 9, wherein the response message including information based on the user input is sent back when the response message is determined. 11. When the mobile computer management apparatus has transmitted a message indicating that the validity of the user has not been confirmed to the returned response message for a predetermined number of consecutive times, 11. The mobile computer device according to claim 9, wherein transmission of a registration request message from the own device thereafter is suppressed. 12. The mobile computer manages current location information of the mobile computer and transfers a packet addressed to the mobile computer to the current location of the mobile computer so that the mobile computer can perform communication by moving between networks. A method of registering with a mobile computer management device, wherein the mobile computer is addressed to the mobile computer management device installed in the home network when connected to a destination outside the home network of the mobile computer. Transmitting a registration message including information on the current position, the mobile computer management device checks the validity of the user of the mobile computer using information based on a user input transmitted from the mobile computer, and Registering the current location of the mobile computer when it is determined that the mobile computer is valid. 13. A method of registering a mobile computer in a mobile computer management device installed in a home network of the mobile computer and enabling the mobile computer to move between networks and perform communication, the method comprising: When registering information on the current position of the mobile computer based on the registration message, prior to execution of this registration, the validity of the user of the mobile computer is checked using information based on the user input received from the mobile computer. Controlling the execution of registration of the information of the current position based on the check result, and transferring a packet addressed to the mobile computer to the current position of the mobile computer based on the information on the execution of the registration. Mobile computer registration method. 14. A mobile computer registration method for a mobile computer device capable of performing communication by moving between mutually connected networks, comprising the steps of: The mobile computer, which has received the registration message, transmits a registration message including information on the current position to a mobile computer management device having means for transferring a packet addressed to the own device to the current position of the own device. When receiving a return request message returned from the management device and requesting the return of information for user authentication, the mobile computer management device writes a response message in which information based on user input is written as information for user authentication. A method for registering a mobile computer, which is returned to