Method for admitting or intercepting selectively access to internet by users on a private network

Abstract

The present invention relates to a method for selectively allowing and blocking internet access by obtaining a private IP using an agent including a user computer that intends to access the internet through a web browser, comprising the steps of: storing the number of allowed IP policies, which is the number of private IPs available per private network, in a Policy Management Table (PMT); storing IDs, public IPs, and private IPs for user computers currently connected to the internet in an IP pool; executing an agent on user computers intending to access the internet through a web browser to obtain the private IP of the user computer intending to access the internet; based on the obtained private IP, when users of the private IP simultaneously access the internet, comparing the IP pool information with the PMT to ensure that one device subscribed by the internet service provider is allowed internet access, while selectively allowing and blocking internet access for the others according to the number of PMT policies; and, if the result of the comparison with the policy indicates that the private IP is blocked from internet access, redirecting the user by transmitting a page embedded with a function that blocks internet access by analyzing packets, instead of the page requested by the user, so that the user receives the page first. Includes.

Description

Technology Field

[0001] The present invention relates to a method for selecting clients capable of simultaneous internet use in a private network and allowing or blocking internet access. More specifically, it relates to a technology for obtaining a private IP and selectively allowing or blocking internet access by utilizing an agent including a user computer that intends to access the internet through a web browser. Background Technology

[0002] Recently, it is common for subscribers to share a single public IP address and for multiple users to use an IP sharing router simultaneously. Additionally, there is a growing trend of companies and enterprises configuring and using NAT. However, such cases are accompanied by serious problems, including increased network traffic, hacking, viruses, and worms.

[0003] However, while it is necessary to track the actual user's IP address to identify the user causing these problems, the user's actual IP address is converted to a public IP address when passing through NAT or an IP router, making it impossible to track the actual IP address from the outside. Furthermore, unlike public IPs, where information regarding which public IPs are in use on the network can be identified through domains or Whois, private IPs lack such information; consequently, it is impossible to determine how many private IPs are being used for a specific public IP.

[0004] Meanwhile, in the infrastructure built by existing internet service providers, equipment and network maintenance costs and network speeds are limited, whereas indiscriminate traffic increases occur on a single line due to NAT, routers, etc. As a result, users who use only one line normally, or those who apply for and use multiple lines normally, are suffering significant damages.

[0005] Prior Patent No. 10-0723657 addresses the aforementioned problem and relates to a technology for distinguishing private IP users who are simultaneously using the Internet with the same public IP. The prior patent utilizes an applet already installed on a computer, in which the applet transmits the public IP and private IP currently being used by the user's computer to be connected to a server. However, since recent browsers restrict the use of applets, there are limitations to allowing or blocking Internet access using applets. The problem to be solved

[0006] The objective of the present invention is to propose a technology that uses an agent installed on a user's computer to obtain a private IP and selectively allow and block internet access.

[0007] The objective of the present invention is to provide a selective internet access blocking method that can identify private IP users using the internet with the same public IP simultaneously, thereby enabling tracking users who use the internet improperly or for unauthorized purposes and blocking their internet access.

[0008] However, the technical problems that the present invention aims to solve are not limited to the above problems, and can be expanded in various ways without departing from the technical concept and scope of the present invention. means of solving the problem

[0009] A method for selecting clients that can simultaneously use the Internet in a private network according to an embodiment of the present invention and allowing and blocking Internet access comprises: a step of storing the number of allowed IP policies, which is the number of private IPs available for each private network, in a Policy Management Table (PMT); a step of storing an ID, a public IP, and a private IP in an IP pool for user computers currently connected to the Internet; a step of executing an agent on user computers that intend to connect to the Internet through a web browser to obtain the private IP of the user computer intending to connect to the Internet; a step of, based on the obtained private IP, when users of the private IP simultaneously connect to the Internet, comparing the IP pool information with the PMT to ensure that one device subscribed by the Internet service provider is allowed to access the Internet, and selectively allowing and blocking the Internet for the others according to the number of PMT policies; and a step of redirecting the user by transmitting a page in which a function that blocks Internet access is embedded by analyzing packets instead of the page requested by the user, so that the user can receive it first.

[0010] The step of obtaining the private IP of the user computer can use an agent that is executed and completed simultaneously with the completion of booting of the user computer, regardless of whether a web browser is running, maintains a waiting state, and enters an active mode upon a call from the server.

[0011] In addition, the method for selecting clients capable of simultaneously using the Internet in a private network according to an embodiment of the present invention and allowing and blocking Internet access further includes the step of counting the number of private IP users with the same ID as the public IP stored in the IP pool when there are IDs and public IPs identical to the user's ID and public IP in the IP pool, but no private IPs identical to the user's private IP exist therein; and if the count value is less than the number of policies specified in the policy table, the Internet access of the user computer intending to access the Internet is permitted, and if the count value is greater than or equal to the number of policies specified in the policy table, the Internet access of the user computer intending to access the Internet is blocked.

[0012] In addition, the method for selecting clients capable of simultaneously using the Internet in a private network according to an embodiment of the present invention and allowing and blocking Internet access may further include the step of informing that, in the case of a private IP where Internet access is blocked, a page with a function performing a specific role transmitted is blocked, and providing an allowed IP change button, and when the allowed IP change button is selected, selectively blocking one from the list of IPs of the corresponding private network in the IP pool and allowing Internet access for a user computer that wishes to access the Internet.

[0013] In addition, the method for selecting clients capable of simultaneously using the Internet in a private network according to an embodiment of the present invention and allowing or blocking Internet access may further include the step of inspecting the IP pool at preset intervals, and if there is no history of Internet usage of a user computer stored in the IP pool for a certain period of time, removing that list from the IP pool. Effects of the invention

[0014] According to an embodiment of the present invention, an agent installed on a user computer can be used to obtain a private IP and selectively allow and block internet access.

[0015] According to an embodiment of the present invention, by selectively allowing and blocking users who can simultaneously use the Internet within a private network using a specific public IP, it is possible to allow and block an unauthorized number of unspecified TCP / IP-based Internet users.

[0016] According to an embodiment of the present invention, by analyzing TCP / IP packets and redirecting all sessions that access a domain with a primary domain for a shared target from a requested page, the private IP of a user within a private network using a specific public IP (Internet IP) can be identified, thereby enabling accurate identification of user information that is simultaneously using the Internet.

[0017] According to an embodiment of the present invention, accurate analysis is made possible by creating a database of user information, and by using the database of IP pool information and jobs, when private IP users simultaneously access the internet, the internet can be selectively allowed and blocked under a TCP / IP-based private network.

[0018] According to an embodiment of the present invention, for users intending to access the Internet, it is possible to determine whether a user is using a router and whether they are using more than the allowed number of private IPs, without requiring user recognition or authentication, thereby enabling effective permission or blocking of Internet access. While it is possible to identify which public IPs are in use on a network and determine public IP information using domains, Whois, etc., it was previously impossible to determine the IP information used for private IPs; however, this technology provides a basis for determining how many private IPs are in use for a specific public IP.

[0019] According to an embodiment of the present invention, it is possible to distinguish private IP users who use the internet with the same public IP at the same time, thereby providing a means to track and charge users who use the internet improperly or for unauthorized purposes.

[0020] However, the effects of the present invention are not limited to the above effects and can be extended in various ways without departing from the technical concept and scope of the present invention. Brief explanation of the drawing

[0021] FIG. 1 illustrates a configuration diagram of a system applying a method for allowing and blocking internet access according to an embodiment of the present invention. FIG. 2 illustrates an example of a policy table (PMT) according to an embodiment of the present invention. FIG. 3 illustrates a signal flow diagram for a method of allowing and blocking internet access according to an embodiment of the present invention. Figure 4 illustrates a diagram showing the permission and blocking of internet access when only one line of internet usage is allowed. Figure 5 illustrates a diagram showing the permission and blocking of internet access when only three lines of internet usage are allowed. Figure 6 is a table illustrating the IP pool in Figure 5. Figure 7 illustrates a diagram showing a module that compares IP pool information and PMT. Specific details for implementing the invention

[0022] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0023] The terms used herein are for describing the embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used herein, "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components, steps, actions, and / or elements to the mentioned components, steps, actions, and / or elements.

[0024] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0025] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the attached drawings. Identical components in the drawings are denoted by the same reference numerals, and redundant descriptions of identical components are omitted.

[0027] FIG. 1 illustrates a configuration diagram of a system applying a method for allowing and blocking internet access according to an embodiment of the present invention. FIG. 2 also illustrates an example of a policy table (PMT) according to an embodiment of the present invention.

[0028] A system (100) that applies a method for selecting clients capable of simultaneous internet use in a private network according to an embodiment of the present invention and allowing and blocking internet access includes a server (10), an IP pool (11), and a policy table (12).

[0029] The server (10) performs the function of selectively allowing and blocking internet access for user computers (Cn) that wish to access the internet of the private network (N). The private network (N) has one ID and one public IP configured, and multiple user computers (C1, C2, …, Cn) are connected to each.

[0030] In the case of a private network (N) that does not use a router, only one user computer among the user computers (C1, C2, …, Cn) can connect. However, as shown in FIG. 1, in the case of a private network (N) that uses a router (20), multiple user computers (C1, C2, …, Cn) can connect simultaneously using different private IPs through the router (20).

[0031] The server (10) analyzes the TCP / IP packets transmitted from the user computer (Cn) connected to the internet and redirects all sessions connecting to the domain that has a primary domain for the shared target on the requested page, thereby identifying the user's private IP within a private network (N) using a specific public IP (Internet IP).

[0032] The server (10) stores the IDs, public IPs, and private IPs of user computers connected to the internet in the IP pool (11). Afterward, the server (10) registers a job scheduler that operates at regular intervals so that the IP pool (11) can maintain the latest information. At this time, the regular time may be about 10 minutes, but is not limited to this and can be pre-set by an administrator.

[0033] As described above, the server (10) selectively allows and blocks access to the internet based on TCP / IP when private IP users access the internet simultaneously using IP pool information and jobs stored in a database. To this end, the server (10) has a policy management table (12) that stores the number of private IPs that can be accessed simultaneously, and blocks and allows internet access for user computers (Cn) of the private network (N) according to the number of private IPs stored in the policy management table (12).

[0034] As illustrated in FIG. 2, the policy table (12) stores an ID and the number of allowed policies for that ID. Accordingly, the server (10) allows connections up to the number of allowed private IPs in the private network (N) using the router (20) based on the policy table (12).

[0036] FIG. 3 illustrates a signal flow diagram for a method of allowing and blocking internet access according to an embodiment of the present invention.

[0037] Figure 3 is a flowchart showing a method for allowing and blocking internet access according to an embodiment of the present invention using an agent method rather than an applet when the browser version capable of executing an applet is not available.

[0038] Referring to FIG. 3, an agent on a user computer (C) is executed immediately after the user computer starts and enters a waiting state (step S300). At this time, the agent represents a process operating on the client (or user computer). The agent used in the present invention is executed and enters a waiting state as soon as the user computer finishes booting, regardless of whether a web browser is running, and enters an active mode upon a call from a security server.

[0039] In steps S301 and S302, the user on the user computer (C) launches a web browser and requests the HTTP of the domain to be accessed. Accordingly, the server (10) analyzes the TCP / IP packets and redirects all sessions connecting to the domain containing the primary domain for the sharing target from the requested page, and calls the agent (step S303).

[0040] At this time, the redirection page has a frame structure of two or more layers, with the frame that displays the webpage the user originally intended to access being composed of 100% (hereinafter referred to as the 100% frame) and the remaining frames being composed of 0% (hereinafter referred to as the 0% frame). The frame with a frame size of 0% is a frame that executes a module, and the 100% frame is a frame that provides information about the page the user originally requested via HTTP and a blocked page.

[0041] When an event occurs through a call, the public IP and private IP currently being used by the user computer (C) to connect are transmitted to the server (10) (step S304). Methods for the agent within the user computer (C) to recognize the call include direct communication, packet capture, and calling the agent via the web. At this time, during the process of step S304, the server (10) can protect the IP information of the user computer (C) through encryption.

[0042] To specifically explain the steps S302 to S304 described above for detecting the public IP and private IP of a user computer (C) within a private network, the server (10) calls an agent after transmitting a notification window from a notification web server using the HTTP protocol when the user computer (C) uses the internet through a web browser. Since there are technically various methods for the calling method, no restrictions are placed on the communication mechanism (TCP-based, UDP-based, etc.) between the agent and the server (10).

[0043] After the call is made, the agent retrieves the private IP of the user computer (C), includes it in the data, and transmits it to the server (10). At this time, the IP and Port of the server (10) may be transmitted during the call, or they may be transmitted via the IP and Port fixed within the agent. The private IP of the user computer (C) is transmitted via the corresponding IP and Port, including it in the data.

[0044] Next, the packet that reached the server (10) was transmitted via the user's public IP, and since the data includes a private IP, both the public IP and the private IP can be detected, and the server (10) stores this in a database.

[0045] In order to protect IP information in intermediate devices (firewall, IPS, IDS, etc.) during the process of transmitting private IP in the aforementioned steps, the agent may include a process of encryption and the server (10) may include a process of decryption.

[0046] The server (10) explains the process of allowing and blocking internet usage for the user who is currently trying to connect, using the user's public IP and private IP obtained in this way.

[0047] First, when a user connects to use the Internet, it is checked whether the user's ID exists in the IP pool (step S305). If the user's ID does not exist in the IP pool (step S306), since the user has connected from a new private network, the user's ID, public IP, private IP, and connection time are registered in the IP pool, the currently connected user is allowed to use the Internet normally (step S307), and the requested HTTP page information is displayed (step S308).

[0048] And, if there is an ID, public IP, and private IP in the IP pool that are identical to the user's ID, public IP, and private IP (step S309), since the user is already connected, the connection time of the corresponding user is modified and the internet is used normally (step S307), and the requested HTTP page information is displayed (step S308).

[0049] However, if there is an ID and public IP in the IP pool that are identical to the user's ID and public IP, but no private IP that is identical to the user's private IP, the following two cases are processed by considering the number of policies in the PMT (Policy Management Table).

[0050] First, count the number of private IP users with the same ID stored in the IP pool, and in the first case where the result is less than the number of policies in the PMT (Policy Management Table) (step S310), register the ID, public IP, private IP, and connection time in the IP pool, allow the currently connected user to use the internet normally (step S307), and display the requested http page information (step S308).

[0051] In the second case, when the number of private IP users with the same ID stored in the IP pool is counted and the result is greater than or equal to the number of policies in the PMT (Policy Management Table), the currently connected user is blocked from using the Internet (step S311). The blocking is performed by receiving the result value of the module executed in the 0% frame and controlling the 100% frame according to the result value.

[0052] At this point, if the result is determined to be internet allowed, the HTTP page requested by the user is provided, and if it is determined to be internet blocked, a connection blocking indicator screen is displayed in the 100% frame (step S312). A "Change Allowed IP" button is displayed on the connection blocking indicator screen, and when this Change Allowed IP button is selected, the internet usage rights of other users existing in the current IP pool who use the same ID as the user currently attempting to connect are blocked, and the user currently attempting to connect gains internet usage rights.

[0053] Then, a job scheduler is registered to operate at regular intervals (10 minutes) so that the IP pool can maintain the latest information (step S313). At this time, the criteria for the job scheduler to keep the contents of the IP pool up to date is to check the registration time and delete records that have not changed for a certain period of time, thereby continuously maintaining the latest information.

[0054] The present invention selectively allows and blocks private IPs of users who can use the internet while proceeding in the same manner as above.

[0056] Figure 4 illustrates a diagram showing the permission and blocking of internet access when only one line of internet usage is allowed.

[0057] When allowing only one line of internet usage in the PMT (Policy Management Table), up to one private IP user using the same ID and the same public IP is allowed, and the rest are blocked.

[0058] As shown in Figure 4, users attempting to access the internet are A, B, and C, and they are all private IP users using the same ID and the same public IP. Since only one line of internet usage is allowed in this case, internet access is permitted by giving priority to the first user to connect.

[0059] First, when user 192.168.0.1(A) attempts to access the internet for the first time, check the IP pool to see if there is a private IP user with the same ID and the same public IP. If there is not, register the ID, public IP, private IP, and connection time in the IP pool to allow access to the internet.

[0060] After that, since user 192.168.0.1(A) continues to use the internet until 20 minutes, users 192.168.0.2(B) or 192.168.0.3(C) are blocked from using the internet even if they attempt to connect. At this time, when the JOB scheduler runs at 30 minutes, the record of user 192.168.0.1(A), who was currently using the internet, is deleted from the IP pool because there is no usage history between 20 minutes and 30 minutes.

[0061] When user 192.168.0.3(C) attempts to access the internet at 31 minutes, there are no private IP users in the IP pool using the same ID and the same public IP, so user 192.168.0.3(C) registers the ID, public IP, private IP, and connection time in the IP pool, and then user 192.168.0.3(C) is able to access the internet. As user 192.168.0.3(C) accesses the internet until 70 minutes, private IP users 192.168.0.1(A) and 192.168.0.2(B) continue to attempt to access the internet but fail to do so, and a connection blocking screen is displayed on the monitor screens of users A and B. At this time, if user 192.168.0.2(B) wants to use the Internet, he / she clicks the "Change Allowed IP" button displayed on the connection blocking screen on his / her monitor screen to change user 192.168.0.3(C), who exists in the current IP pool and uses the same ID as user B, to 192.168.0.2(B), thereby blocking user 192.168.0.3(C) and granting user 192.168.0.2(B) the right to use the Internet.

[0063] FIG. 5 illustrates a diagram showing the permission and blocking of internet access when only three lines of internet usage are allowed. In addition, FIG. 6 illustrates the IP pool in FIG. 5 as a table, and FIG. 7 illustrates a diagram showing a module that compares IP pool information with PMT.

[0064] In cases where only 3 lines are allowed for internet usage in the PMT (Policy Management Table), up to 3 private IP users using the same ID and the same public IP are allowed, and the rest are blocked.

[0065] As shown in Figure 5, the users attempting to access the internet are A, B, C, and D, and they are all private IP users using the same ID and the same public IP. Since only three lines of internet access are allowed in this case, internet access is permitted by giving priority to the three users who connect first.

[0066] First, when user 192.168.0.1(A) attempts to access the internet for the first time, check the IP pool for any private IP users with the same ID and the same public IP. If there are none, register the ID, public IP, private IP, and connection time in the IP pool to allow access to the internet.

[0067] After that, if user 192.168.0.2(B) attempts to connect at 10 minutes, check if there is a public IP with the same ID in the IP pool. If a private IP exists in the IP pool, allow access to the internet. If it does not exist, count the number of private IP users with the same ID and public IP in the IP pool. If the result (here, return value: 1) is less than the number of PMT policies (here, 3 lines allowed), register the private IP of 192.168.0.2(B) and allow access to the internet. Conversely, if the result is greater than or equal to the number of PMT policies, block access to the internet.

[0068] Here, at the time when user 192.168.0.2(B) attempts to connect, the number of private IP users with the same ID and the same public IP in the IP pool is 1, which is less than the number of policies in PMT, 3, so the private IP of 192.168.0.2(B) is registered and allowed to use the Internet.

[0069] Next, when user 192.168.0.3(C) attempts to connect at 15 minutes, check if there is a public IP with the same ID in the IP pool. Since the number of private IP users with the same ID and public IP in the IP pool at the time user 192.168.0.3(C) attempts to connect is 2, which is less than the number of PMT policies of 3, register the private IP of 192.168.0.3(C) and allow it to use the internet.

[0070] After that, when user 192.168.0.4(D) attempts to connect at 17 minutes, it is confirmed that there is a public IP with the same ID in the IP pool. Since the number of private IP users with the same ID and public IP in the IP pool at the time user 192.168.0.4(D) attempts to connect is 3, the number of PMT policies is not less than 3, so the private IP of 192.168.0.4(D) is not registered and internet usage is blocked.

[0071] By continuing in the same manner as above, you can selectively allow and block internet access under a private network.

[0073] The system or device described above may be implemented as a hardware component, a software component, and / or a combination of a hardware component and a software component. For example, the device and component described in the embodiments may be implemented using one or more general-purpose or special-purpose computers, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a Field Programmable Gate Array (FPGA), a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing unit may execute an operating system (OS) and one or more software applications executed on said operating system. Additionally, the processing unit may access, store, manipulate, process, and generate data in response to the execution of the software. For ease of understanding, the processing unit may be described as being used as a single unit, but those skilled in the art will understand that the processing unit may include multiple processing elements and / or multiple types of processing elements. For example, the processing unit may include multiple processors or one processor and one controller. Additionally, other processing configurations, such as parallel processors, are also possible.

[0075] Software may include computer programs, code, instructions, or a combination of one or more of these, and may configure a processing unit to operate as desired or command the processing unit independently or collectively. Software and / or data may be permanently or temporarily embodied in any type of machine, component, physical device, virtual equipment, computer storage medium or device, or transmitted signal wave so as to be interpreted by the processing unit or to provide instructions or data to the processing unit. Software may be distributed over networked computer systems and may be stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

[0077] The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., either alone or in combination. The program instructions recorded on the medium may be those specifically designed and configured for the embodiment, or they may be those known and available to those skilled in the art of computer software. Examples of computer-readable recording media include hard disks, magneto-optical media, solid-state drives (SSDs), and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Examples of program instructions include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc. The hardware devices described above may be configured to operate as one or more software modules to perform the operation of the embodiment, and vice versa.

[0079] Although the embodiments have been described above with reference to limited examples and drawings, those skilled in the art can make various modifications and variations from the description above. For example, suitable results can be achieved even if the described techniques are performed in a different order than described, and / or the components of the described system, structure, device, circuit, etc. are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents.

[0081] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims set forth below.

Claims

Claim 1 A method for selecting clients capable of simultaneously using the Internet in a private network and allowing or blocking Internet access, comprising: a step of storing the number of allowed IP policies, which is the number of private IPs available per private network, in a Policy Management Table (PMT); a step of storing the ID, public IP, and private IP of user computers currently connected to the Internet in an IP pool; a step of executing an agent on user computers intending to connect to the Internet via a web browser to obtain the private IP of the user computer intending to connect to the Internet; a step of, based on the obtained private IP, when users of the private IP simultaneously connect to the Internet, comparing the IP pool information with the PMT to ensure that one device subscribed by the Internet Service Provider is allowed to access the Internet, while selectively allowing or blocking the Internet for the remainder according to the number of PMT policies; a step of counting the number of private IP users with the same ID as the public IP stored in the IP pool when there is an ID and public IP identical to the user's ID and public IP in the IP pool, but no private IP identical to the user's private IP exists; and the count A step of allowing internet access for a user computer intending to access the internet if the value is less than the number of policies specified in the policy table, and blocking internet access for a user computer intending to access the internet if the count value is greater than or equal to the number of policies specified in the policy table; a step of redirecting the user by transmitting a page that has a function to block internet access embedded in it by analyzing packets instead of the page requested by the user, if the result of comparison with the policy is that the private IP is blocked from internet access;A method comprising: a step of providing information that, in the case of a private IP with blocked internet access, a page with a function performing a specific role transmitted is blocked from access, and providing a button to change allowed IP, wherein when the button to change allowed IP is selected, one of the IPs in the list of the corresponding private network in the IP pool is selectively blocked and the internet access of a user computer that wishes to access the internet is allowed; and a step of inspecting the IP pool at preset intervals and removing the list from the IP pool if there is no history of internet usage by the user computer stored in the IP pool for a certain period of time, wherein the step of obtaining the private IP of the user computer is characterized by using an agent that is executed and completed simultaneously with the completion of booting of the user computer, regardless of whether a web browser is running, maintains a standby state, and enters an active mode upon a call from a server. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete

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