JP2006013891A - COMPUTER NETWORK SYSTEM AND ITS QoS SETTING METHOD - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a computer network system which dynamically sets QoS (Quality of Service) for each user, and operates by only a priority control function supported by a router. <P>SOLUTION: A user authentication QoS server 10 performs user authentication of a client device 21 which request authentication by a user authentication part 12 if the user is authenticated, reads out a QoS class associated with a user name corresponding to the authentication from a memory part 13, and notifies to a router 31 and a router 3k through a QoS policy distribution part 11 so that the QoS is rewritten. The router 31 detects a sender's address in a coming packet, and if it agrees with the sender's address notified from the user authentication QoS server 10, rewrites the QoS class in the packet. The router 3k detects the destination's address in the coming packet, and if it agrees with the sender's address notified from the user authentication QoS server 10, rewrites the QoS class in the packet. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a computer network system and a QoS (Quality of Services) setting method thereof, and more particularly to a computer network system that dynamically changes a QoS class based on a QoS policy and a QoS setting method in this system.

  In a computer network system composed of a client and a server, service quality (QoS) may be set and operated so that the priority of processing in the network differs for each client. In such a computer network system, there is a system in which an apparatus (server) that manages authentication and QoS policy is provided in the system, and this apparatus distributes QoS information to devices that perform path control in the computer network system. .

  For example, in Patent Document 1, route information settings for routers and switches in the entire network, bandwidth and packet connection priority settings, and access right settings in gateways are automatically set based on pre-registered policies. An access control system that can perform a flexible network environment is disclosed. This system is an access control system for controlling communication connection / connection quality of the entire network in a wide area computer communication network connecting a plurality of local area networks, and connecting a plurality of local area networks. Information relating to a route for use, authentication information of a user who uses a local area network, and policy information for managing user access are received in advance and each time a user terminal logs in Based on at least the access information including the user authentication information and the authentication information registered in the storage unit, the authentication process for the user is executed. If the authentication process is successful, the wide area computer communication network and a plurality of local areas・ Routers or switches that make up the network Against, and executes processing for updating the setting based on the information relating to the route, in which includes a processing unit for executing processing for updating the setting based on the policy information corresponding to the user.

  Patent Document 2 discloses a user authentication QoS policy management system in which a PC client is authenticated by an authentication server via a LAN switch, and is also controlled for each user to access a business server and access priority. Is disclosed. In this system, a PC client that transmits logon information to a LAN switch, and logon information transmitted from the PC client is transmitted to the authentication server, and address information of the PC client is stored, and access control information is transmitted from the authentication server. And a QoS switch that controls the access of the PC client to the business server based on the access control information, and controls the access priority of the PC client to the business server based on the QoS information. The authentication is performed based on the transmitted logon information, and when the authentication result is positive, the access is performed by the authentication server and the LAN switch that transmit the access control information and QoS information corresponding to the logon information to the LAN switch. A configuration having a business server that receives the access from the PC client that received the control in accordance with control information and QoS information.

  Further, Patent Document 3 discloses a connection with a network such as a dial-up connection subscriber or a subscriber using a mobile terminal in IP-QoS control such as Diff-serv provided in an IP (Internet Protocol) network system. For a remote subscriber terminal whose node cannot be specified, a QoS service according to an SLA (Service Level Agreement) for each subscriber is provided for connection from any node to the network, and these QoS services are provided in the network. A system that centrally manages the system is disclosed.

JP 2004-48340 A (FIGS. 1 and 3) JP 2004-32525 A (FIGS. 1 and 2) JP 2003-234770 A (FIGS. 1 and 2)

  In recent computer network systems, an Internet protocol (IP) is often used as a network layer communication protocol, and is often configured as an IP network. Incidentally, the system described in Patent Document 1 has route information, and dynamically sets routes for all routers on the route. However, it is extremely difficult to implement such a system in a normal destination address-based IP network. That is, in a general IP network, routers autonomously control routes by using a routing protocol such as RIP (Routing Information Protocol) or OSPF (Open Shortest Path First), and control routes from other systems. Is very difficult. In order to realize this, an MPLS (Multiprotocol Label Switching) network is required and cannot be applied to a general IP network.

  On the other hand, in the system described in Patent Document 2, the LAN switch transmits logon information transmitted from the PC client to the authentication server, stores address information of the PC client, and receives access control information and The QoS information is received, the access control information is used to control the access of the PC client to the business server, and the access priority of the PC client to the business server is controlled based on the QoS information. Such a LAN switch is dedicated to the system and cannot be realized by a router that operates only with a priority control function used in a general IP network.

  In the system described in Patent Document 3, the edge node makes an authentication request to the authentication server in order to determine whether or not the subscriber can connect, and if the connection is possible as a result of the authentication, the edge node It operates to apply the Diff-serv information to the subscriber session based on the packet identification ID and policy map ID. Such an edge node cannot be realized by a router that operates only with a priority control function used in a general IP network.

  Accordingly, an object of the present invention is to provide a computer network system that operates by dynamically setting QoS for each user only by a priority control function supported by a general IP router, and a QoS setting method thereof. .

  A computer network system according to a first aspect of the present invention that achieves the above object is a system in which a first network and a second network are connected via a router. The system includes a first service class rewriting unit included in the first network and a second service class rewriting unit included in the second network. A distribution unit that distributes a QoS (Quality of Services) policy to the first service class rewriting unit and the second service class rewriting unit; a user authentication unit that processes an authentication request from a user; And a storage unit that stores a user name and a QoS class associated with the user name. The QoS server authenticates the user who requested the authentication by the user authentication unit. When the user is authenticated, the QoS server reads the QoS class associated with the user name corresponding to the authentication request from the storage unit and receives it when the authentication is requested. The QoS class in the packet having the source address that matches the source address in the received packet is notified to the first service class rewriting means via the distribution unit so that the QoS class in the packet is rewritten to the read QoS class, and received at the time of the authentication request The QoS class in the packet having the transmission destination address that matches the transmission source address in the received packet is notified to the second service class rewriting means via the distribution unit so as to be rewritten to the read QoS class.

  In the computer network system according to the first development mode, a client device used by a user is included in the first network, and a server device that transmits and receives packets to and from the client device in the second network. May be included.

  In the computer network system according to the second deployment mode, the first service class rewriting means is a first router included in the first network, and the second service class rewriting means is included in the second network. The first router and the second router may be configured to be connected directly or via one or more other routers.

  In the computer network system of the third development form, a packet sent from a client device used by an authenticated user to a server device reaches the server device after the QoS class is rewritten by the first router, and the server The packet sent from the apparatus to the client apparatus may reach the client apparatus after the QoS class is rewritten by the second router.

  In the computer network system according to the fourth deployment mode, the first service class rewriting unit is a first QoS agent existing in the client device, and the second service class rewriting unit exists in the server device. A second QoS agent, wherein a first router included in the first network and a second router included in the second network are connected directly or via one or more other routers; May be configured.

  In the computer network system according to the fifth deployment mode, a packet sent from the client device used by the authenticated user to the server device reaches the server device with the QoS class being rewritten by the first QoS agent, Packets sent from the server device to the client device may reach the client device after the QoS class is rewritten by the second QoS agent.

  In the computer network system according to the sixth embodiment, the packet may be an IP (Internet Protocol) packet, and the QoS class may be set in the service class existing in the header of the IP packet.

  In the QoS server according to the second aspect of the present invention, a first network including a first service class rewriting unit and a second network including a second service class rewriting unit are connected via a router. A QoS server for setting a QoS class in a computer network system. The QoS server includes a user authentication unit that processes an authentication request from a user, a storage unit that stores a user name to be authenticated and a QoS class associated with the user name, and a first service class rewriting unit. And a distribution unit that distributes the QoS policy to the second service class rewriting means. Further, when a user who has requested authentication is authenticated by the user authentication unit and the user is authenticated, the QoS class associated with the user name corresponding to the authentication request is read from the storage unit, and the packet received at the time of the authentication request The packet received at the time of the authentication request is notified to the first service class rewriting means via the distribution unit so that the QoS class in the packet having the source address matching the source address in the packet is rewritten to the read QoS class. The QoS class in the packet having the transmission destination address that matches the transmission source address is notified to the second service class rewriting means via the distribution unit so that the QoS class is rewritten to the read QoS class.

  In the QoS setting method in the computer network system according to the third aspect of the present invention, the first network including the first service class rewriting unit and the second network including the second service class rewriting unit are routers. The QoS server sets a QoS class in a computer network system connected through the QoS server. The method includes a step of authenticating a user who has requested authentication, a step of reading a QoS class stored in association with the user name of the user when the user is authenticated, A step of notifying the first service class rewriting means to rewrite the QoS class in the packet having the source address matching the source address in the received packet to the read QoS class, and the packet received at the time of the authentication request And notifying the second service class rewriting means so as to rewrite the QoS class in the packet having the transmission destination address that matches the transmission source address to the read QoS class.

  In the QoS setting method in the computer network system of the first deployment mode, a packet sent from a client device in the first network used by an authenticated user to a server device in the second network is The QoS class is rewritten by the first service class rewriting unit and reaches the server device, and the packet sent from the server device to the client device is rewritten by the second service class rewriting unit and the QoS class is rewritten. You may make it arrive at an apparatus.

  In the QoS setting method in the computer network system according to the second deployment mode, the first service class rewriting means is a first router included in the first network, and the second service class rewriting means is the second service class rewriting means. The first router and the second router may be connected directly or via one or more other routers.

  In the QoS setting method in the computer network system according to the third development mode, the first service class rewriting means is a first QoS agent existing in the client device, and the second service class rewriting means is the server device. The second router included in the first network and the second router included in the second network may be directly or via one or more other routers. It may be connected.

  In the QoS setting method in the computer network system according to the fourth development mode, the packet may be an IP (Internet Protocol) packet, and the QoS class may be set in the service class existing in the header of the IP packet.

  According to the present invention, the user authentication function is incorporated into the user authentication QoS server, and the edge router or the user authentication QoS agent is set so as to give priority to communication of the authenticated user. Therefore, the computer network system can be configured using a router that operates only with the priority control function used in a general IP network, and can be operated by dynamically changing the QoS for each user.

  In the computer network system according to the embodiment of the present invention, a first network and a second network are connected via two or more routers, and a client device and a first service class rewrite are connected in the first network. Means. The second network includes a server device and second service class rewriting means. Further, the computer network system includes a QoS server. The QoS server distributes a QoS (Quality of Services) policy to the first and second service class rewriting means, and sends an authentication request from the client device. An authentication unit to process, and a storage unit that stores a user name to be authenticated and a QoS class associated with the user name.

  The QoS server authenticates the user who requested the authentication by the user authentication unit. When the user is authenticated, the QoS server reads out the QoS class associated with the user name corresponding to the authentication from the storage unit and received it at the time of the authentication request. The QoS class in the packet having the source address that matches the source address in the packet is notified to the first service class rewriting means via the distribution unit so as to rewrite the QoS class in the read-out QoS class. In addition, the QoS class in the packet having the destination address that matches the source address in the packet received at the time of the authentication request is notified to the second service class rewriting means via the distribution unit so as to rewrite the QoS class in the read-out QoS class. To do.

  The first service class rewriting means is an agent that exists in the router or client device existing in the first network, detects the source address in the incoming packet, and is notified from the QoS server. If it matches the source address, the QoS class in the packet is rewritten.

  Further, the second service class rewriting means is an agent existing in the router or server device existing in the second network, detects the transmission destination address in the incoming packet, and is notified from the QoS server. If it matches the source address, the QoS class in the packet is rewritten.

  The computer network system operates as described above, and packets sent from the client device used by the authenticated user are distributed according to the priority rewritten by the first service class rewriting means. Further, the packet sent from the server device to the client device used by the authenticated user is distributed according to the priority rewritten by the second service class rewriting means. Such a computer network system incorporates a user authentication function in a conventional QoS server, and provides a QoS function for each user that is dynamically changed with respect to the communication of the authenticated user.

  Therefore, since the computer network system of the present invention is realized only by the priority control function supported by a general IP router, it has a wide range of applications and is effective even in a general corporate network that does not use the service of a telecommunications carrier. It is. Below, based on an Example, it demonstrates in more detail about a computer network system.

  FIG. 1 is a block diagram showing the configuration of a computer network system according to the first embodiment of the present invention. In FIG. 1, the computer network system includes a user authentication QoS server 10, client devices 21 to 2n, routers 31 to 3k that are network relay devices, and various server devices 41 to 4m. The user authentication QoS server 10 has a user authentication unit 12 in addition to the function of distributing a conventional fixed QoS policy to the router, and a QoS policy for distributing a dynamic QoS policy giving priority to authenticated user communication. A distribution unit 11 is provided. The storage unit 13 stores a registered user name, password, QoS class permitted to the user, and the like. The client devices 21 to 2n are personal computers or the like, and perform user authentication by communicating with the user authentication QoS server 10 through a Web browser or the like that is generally used. If authentication is permitted, it connects with predetermined server apparatuses 41-4m and receives provision of various services. The routers 31 to 3k have a function of determining and distributing the route of the IP packet. The server devices 41 to 4m have a function of providing various services in response to requests from the client devices 21 to 2n.

  In the computer network system shown in FIG. 1, the user authentication QoS server 10, the client devices 21 to 2n, and the router 31 are connected to one LAN, and the router 3i (i = 1 to k-1) is connected to the router. 3i + 1, and the router 3k and the server devices 41 to 4m are connected to another LAN. Here, a LAN (not shown) may exist between the router 3i and the router 3i + 1. The network architecture shown in FIG. 1 shows an example, and the present invention is not limited to this.

  Next, IP packets transmitted and received within the computer network system will be described. FIG. 2 is a diagram illustrating the configuration of an IP packet. In FIG. 2, the IP packet 50 includes a header 51 and data 52. Further, the header 51 includes a service class 53 representing the priority, delay, throughput, reliability, etc. of the IP packet 50, a source address 54 representing the IP address of the IP packet 50, and a destination of the IP packet 50. It consists of fields such as a transmission destination address 55 representing an IP address. There are other fields in the header 51, but they are not directly related to the present invention, so that the description thereof is omitted. The service class 53 includes a value for determining priority, such as TOS (Type of Service) or DSCP (Differentiated Services Code Point), and based on this value, priority control of IP packets is performed in a router or the like.

  Next, the operation of the computer network system will be described in detail with reference to FIGS. FIG. 3 is a flowchart showing the operation of the computer network system according to the first embodiment of the present invention.

  First, the user authentication QoS server 10 performs a static QoS setting on all the routers 31 to 3k in the network by a conventional QoS policy distribution function. Specifically, the setting for determining the priority is performed based on the value of TOS or DSCP, which is a field representing the service class in the IP header (step A1). Also, the administrator registers the user name, password, and QoS class permitted to the user in the user authentication QoS server 10 (step A2). The state in which the above steps A1 and A2 are set is set as an initial state (step A3), and then the operation is started.

  At the start of service, the user A logs in to the user authentication QoS server 10 from the client device 21 (step A4). The user authentication QoS server 10 determines authentication based on the contents of the storage unit 13 such as whether or not the user A is registered (step A5). If the authentication fails, the process returns to the initial state (step A3).

  When the authentication is successful, the user authentication QoS server 10 acquires the IP address of the client device 21 of the user A from the authentication packet and the QoS class of the user A from the storage unit 13 (step A6). Then, the routers 31 and 3k (edge routers) are configured to rewrite the TOS or DSCP in the packet whose acquired IP address (the IP address of the client device 21) matches the source address or the destination address to the value of the corresponding QoS class. Set (step A7). Note that the routers 32 to 3k-1 (core routers) are already set in step A1 so that priority control is performed with reference to the TOS or DSCP rewritten by the routers 31 and 3k, so that no new setting is required.

  Thus, the packet whose source or destination is the IP address of the client device 21 is preferentially controlled by all the routers 31 to 3k on the route, and communication between the client device 21 of the user A and the various server devices 41 to 4m. Is protected even when the communication load is high.

  When the service ends, the user authentication QoS server 10 is logged out (step A8). The user authentication QoS server 10 deletes the contents set in step A7 in the routers 31 and 3k (step A9). This returns to the initial state (step A3), and the band preferentially used by user A is released to general users.

  The computer network system according to the first embodiment operates as described above, incorporates a user authentication function in the user authentication QoS server 10, and sets each router in the network to give priority to authenticated user communication. . In other words, the priority control setting of the core router is statically performed at the time of initial introduction, and only the setting of marking (TOS or DSCP rewriting) at the edge router is dynamically performed. Accordingly, the QoS for each user can be dynamically changed and operated by each router.

  Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of a computer network system according to the second embodiment of the present invention. The computer network system shown in FIG. 4 includes a user authentication QoS server 10, client devices 21a to 2na, routers 31 to 3k that are network relay devices, and various server devices 41a to 4ma. 4, the same reference numerals as those in FIG. 1 represent the same items, and the description thereof is omitted. The client devices 21a to 2na and the server devices 41a to 4ma are substantially the same as the client devices 21 to 2n and the server devices 41 to 4m shown in FIG. 1, respectively, but the client devices 21a to 2na are respectively user authentication QoS agents. 15, and the server apparatuses 41 a to 4 ma are different from each other in that they each include a user authentication QoS agent 16.

  Next, the operation of the computer network system will be described in detail with reference to FIGS. FIG. 5 is a flowchart showing the operation of the computer network system according to the second embodiment of the present invention.

  First, the user authentication QoS server 10 performs a static QoS setting on all the routers 31 to 3k in the network by a conventional QoS policy distribution function. Specifically, the setting for determining the priority is performed based on the value of TOS or DSCP in the IP header (step B1). Further, the administrator registers the user name, password, and QoS class permitted to the user in the user authentication QoS server 10 (step B2). The state where the above steps B1 and B2 are set is used as an initial state (step B3).

  At the start of the service, the user A logs in to the user authentication QoS server 10 from the client device 21a (step B4). The user authentication QoS server 10 determines authentication based on the contents of the storage unit 13 such as whether or not the user A is registered (step B5). If the authentication fails, the process returns to the initial state (step B3).

  When the authentication is successful, the user authentication QoS server 10 acquires the IP address of the client device 21a used by the user A from the packet at the time of authentication and the QoS class of the user A from the storage unit 13, and the user of the client device 21a The acquired QoS class is notified to the authentication QoS agent 15 (step B6). Also, the acquired IP address of the client device 21a and the acquired QoS class are notified to the user authentication QoS agent 16 of the server devices 41a to 4ma (step B7).

  The user authentication QoS agent 15 of the client device 21a rewrites TOS or DSCP in the transmission packet (step B8). The user authentication QoS agent 16 of the server apparatuses 41a to 4ma rewrites TOS or DSCP in the packet addressed to the client apparatus 21a (step B9). Packets exchanged between the client device 21a and the server devices 41a to 4ma are rewritten to an appropriate TOS or DSCP, and therefore are preferentially controlled by all routers on the route, and the client device 21a of the user A and the server device 41a Communication between ˜4ma is protected even when the communication load is high.

  When the service ends, the user authentication QoS server 10 is logged out. The user authentication QoS server 10 notifies the user authentication QoS agent 15 of the client device 21a and the user authentication QoS agent 16 of the server devices 41a to 4ma so that TOS or DSCP is returned to the normal value (step B10). This returns to the initial state (step B3), and the band that was preferentially used by user A is released to general users.

  The computer network system according to the second embodiment operates as described above, and incorporates a user authentication function in the user authentication QoS server 10 so that the user authentication QoS agent 15 and the user are prioritized so as to give priority to authenticated user communication. The authentication QoS agent 16 is set. Accordingly, the QoS for each user can be dynamically changed by the agent for operation.

1 is a block diagram showing a configuration of a computer network system according to a first example of the present invention. It is a block diagram showing the structure of an IP packet. It is a flowchart showing operation | movement of the computer network system based on 1st Example of this invention. It is a block diagram showing the structure of the computer network system which concerns on 2nd Example of this invention. It is a flowchart showing operation | movement of the computer network system concerning the 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 User authentication QoS server 11 QoS policy distribution part 12 User authentication part 13 Storage | storage part 15, 16 User authentication QoS agent 21-2n, 21a-2na Client apparatus 31-3k Router 41-4m, 41a-4ma Server apparatus 50 IP packet 51 Header 52 Data 53 Service class 54 Source address 55 Destination address

Claims (13)

A computer network system in which a first network and a second network are connected via a router,
First service class rewriting means included in the first network;
Second service class rewriting means included in the second network;
A distribution unit that distributes a quality of service (QoS) policy to the first service class rewriting unit and the second service class rewriting unit, a user authentication unit that processes an authentication request from a user, and an authentication request target A storage unit that stores a user name and a QoS class associated with the user name, and a QoS server,
With
The QoS server authenticates the user requested to be authenticated by the user authenticating unit, and when authenticating the user, the QoS server associates a QoS class associated with the user name corresponding to the authentication request from the storage unit. Read, through the distribution unit, the first service class so that a QoS class in a packet having a source address that matches a source address in the packet received at the time of the authentication request is rewritten to the read QoS class Rewriting means is notified, and the QoS class in the packet having the transmission destination address that matches the transmission source address in the packet received at the time of the authentication request is rewritten to the read QoS class via the distribution unit. And a service class rewriting means of the computer network system. Temu.   The first network includes a client device used by the user, and the second network includes a server device that transmits and receives packets to and from the client device. The computer network system according to claim 1.   The first service class rewriting means is a first router included in the first network, and the second service class rewriting means is a second router included in the second network. 3. The computer network system according to claim 2, wherein the first router and the second router are connected directly or via one or more other routers.   The packet sent from the client device used by the authenticated user to the server device reaches the server device with the QoS class being rewritten by the first router, and the client device sends the packet to the server device. 4. The computer network system according to claim 3, wherein a packet sent to the device reaches the client device after the QoS class is rewritten by the second router.   The first service class rewriting means is a first QoS agent existing in the client apparatus, and the second service class rewriting means is a second QoS agent existing in the server apparatus. The first router included in the first network and the second router included in the second network are connected directly or via one or more other routers. Item 3. The computer network system according to Item 2.   The packet sent from the client device used by the authenticated user to the server device reaches the server device with the QoS class being rewritten by the first QoS agent, and the server device sends the packet to the client device. 6. The computer network system according to claim 5, wherein a packet transmitted toward the packet reaches the client device after the QoS class is rewritten by the second QoS agent.   The said packet is an IP (Internet Protocol) packet, The said QoS class is set to the service class which exists in the header of IP packet, The Claim 1 characterized by the above-mentioned. Computer network system. A QoS server that sets a QoS class in a computer network system in which a first network including a first service class rewriting unit and a second network including a second service class rewriting unit are connected via a router. There,
A user authentication unit for processing an authentication request from a user;
A storage unit for storing a username to be authenticated and a QoS class associated with the username;
A distribution unit for distributing a QoS policy to the first service class rewriting unit and the second service class rewriting unit;
With
When the user who has made an authentication request is authenticated by the user authentication unit and the user is authenticated, the QoS class associated with the user name corresponding to the authentication request is read from the storage unit, and the authentication request The QoS class in a packet having a source address that matches the source address in the received packet is notified to the first service class rewriting means via the distribution unit so as to rewrite the QoS class to the read QoS class. The second service class rewrite via the distribution unit so as to rewrite the QoS class in the packet having the transmission destination address that matches the transmission source address in the packet received at the time of the authentication request to the read QoS class. A QoS server characterized by notifying means. The QoS server sets the QoS class in the computer network system in which the first network including the first service class rewriting unit and the second network including the second service class rewriting unit are connected via the router. A method,
Authenticating a user who has requested authentication; and
When authenticating the user, reading a stored QoS class associated with the user name of the user;
Notifying the first service class rewriting means to rewrite the QoS class in the packet having a source address that matches the source address in the packet received at the time of the authentication request to the read QoS class;
Notifying the second service class rewriting means to rewrite the QoS class in the packet having a destination address that matches the source address in the packet received at the time of the authentication request to the read QoS class;
A QoS setting method in a computer network system, comprising:   A packet sent from the client device in the first network used by the authenticated user to the server device in the second network has a QoS class by the first service class rewriting means. A packet that is rewritten to reach the server device and is sent from the server device to the client device has its QoS class rewritten by the second service class rewriting means to reach the client device. The QoS setting method in the computer network system according to claim 9.   The first service class rewriting means is a first router included in the first network, and the second service class rewriting means is a second router included in the second network. 10. The QoS setting method in a computer network system according to claim 9, wherein the first router and the second router are connected directly or via one or more other routers.   The first service class rewriting means is a first QoS agent existing in the client apparatus, and the second service class rewriting means is a second QoS agent existing in the server apparatus. The first router included in the first network and the second router included in the second network are connected directly or via one or more other routers. Item 11. A QoS setting method in a computer network system according to Item 10. 11. The QoS setting method in a computer network system according to claim 9, wherein the packet is an IP (Internet Protocol) packet, and the QoS class is set in a service class existing in a header of the IP packet. .

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