JP2008005078A - Relay communication system, relay device,method for band control by session, and program thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a relay communication system capable of performing optimum band control by route units. <P>SOLUTION: Once receiving a packet, a route selecting means 11 acquires a current route and holds information on, for example, IP address, protocol number, port number, the route, final use time, etc., in a session information recording section 21. A band control means 12 reads information regarding the route out of the session information recording section 21, specifies the session that the packet being processed belongs to, and reads out pieces of information on all other sessions using the route that the specified session uses to compute a permitted band from those pieces of information. According to the permitted band, the band control means 12 holds the packet in a TCP data buffer section 22, when the packet is a TCP packet and divides a TCP session to perform band control, but performs band control by queueing, when the packet is not a TCP packet. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a relay communication system, a relay apparatus, a session-specific bandwidth control method used in the relay communication system, and a program thereof, and more particularly to bandwidth control in data communication across a plurality of networks.

  In recent years, with the spread of the Internet, for example, a constant connection environment to the Internet such as CATV (CABle TeleVision), xDSL (x Digital Subscriber Line), FTTH (Fiber To The Home) has also spread.

  In addition, with the spread of this always-on environment, applications and contents on the Internet have been diversified, and multimedia applications such as video that require a wide band have appeared.

  In such multimedia applications, required quality such as required bandwidth and timing is high. As a quality assurance mechanism for satisfying the required quality, a bandwidth allocation mechanism such as RSVP (Resource Reservation Protocol) or bandwidth brokering (Bandwidth Brokering) is being considered instead of the conventional best effort service that does not guarantee quality at all. Yes.

  As this bandwidth allocation, a method of dynamically increasing or decreasing the bandwidth used for a user for each user has been proposed (see, for example, Patent Document 1). In this method, a connection service providing means for providing a connection service to a network to a user, a user side connection means for connecting a user terminal to the connection service providing means and enabling the use of the network connection service; Is provided in the communication system.

  In this method, the connection service providing means includes a path control means for determining a transmission destination of input data, a service information storage means for holding service information of a band change service set for each user, a service Additional service control means for controlling the bandwidth change service for each user based on the information is provided.

  Furthermore, as another bandwidth allocation, a method for performing bandwidth-controlled data communication in the case of communication across a plurality of ISPs (Internet Service Providers) has been proposed (see, for example, Patent Document 2). ).

  This method is a method of securing a transmission band in data transfer between two communication apparatuses (content servers) by data transfer across a plurality of ISPs in the Internet. In this case, one of the two communication devices makes an application for securing the bandwidth of the data transmission path on which data transmission is performed to the bandwidth securing mediation server that mediates securing of the transmission bandwidth in the Internet, The bandwidth securing mediation server secures the transmission bandwidth in the data transmission path instead of the two communication devices.

JP2003-8638 JP 2002-344499 A

  In the conventional bandwidth control method described above, in the bandwidth control including the techniques described in Patent Documents 1 and 2 above, the case where the communication path is dynamically changed is not taken into consideration. Despite being, there is a problem that it cannot be used.

  Further, in the conventional bandwidth control method, a technique of changing the interval of ACK (ACKnowledgement) packets is used for control of a TCP (Transmission Control Protocol) session, and packet loss occurs when burst communication occurs. There is a problem that occurs.

  Accordingly, an object of the present invention is to provide a relay communication system, a relay device, a session-specific bandwidth control method used therefor, and a program thereof that can solve the above-described problems and realize optimum bandwidth control for each path. It is in.

A relay communication system according to the present invention is a relay communication system in which a terminal and first and second networks perform bidirectional communication via a relay device,
The relay device selects a route selection unit that selects one of the first and second networks based on a parameter of the packet, and a packet selected for the route selected by the route selection unit. Session information recording means for storing session information determined by parameters, and for each session in communication based on the number of sessions and the amount of communication in the route based on the information of the session information recording means And bandwidth control means for calculating and controlling the permitted bandwidth.

A relay device according to the present invention is a relay device that relays communication between a terminal and first and second networks when performing bidirectional communication,
A route selection unit that selects one of the first and second networks based on a parameter of the packet for a packet passing through its own device, and a route selected by the route selection unit is determined by the parameter of the packet Based on the information of the session information recording means for storing session information and the session information recording means, the permitted bandwidth is calculated for each session in communication based on the number of sessions and the amount of communication on the route. And a bandwidth control means for controlling.

A session-specific bandwidth control method according to the present invention is a session-specific bandwidth control method used in a relay communication system in which a terminal and first and second networks perform bidirectional communication via a relay device,
The relay device selects a packet passing through the own device according to a parameter of the packet and selects one of the first and second networks, and the packet of each packet for each route selected by the route selection unit. Based on the information of the session information recording means for storing the session information determined by the parameters, the permitted bandwidth is calculated for each session in communication based on the number of sessions communicating and the traffic volume on the route. The bandwidth control processing to be controlled is executed.

The program according to the present invention is a program executed by a relay device that relays communication between a terminal and the first and second networks when performing bidirectional communication,
In the central processing unit of the relay device, a route selection process for selecting one of the first and second networks based on a parameter of the packet, and a route selected by the route selection unit. Based on the information of the session information recording means that stores the session information determined by the parameter of the packet, the permitted bandwidth for each session in communication based on the number of sessions communicating and the traffic volume on the route And bandwidth control processing for calculating and controlling.

  That is, according to the relay communication system of the present invention, when performing data communication while dynamically selecting a route between a terminal and a plurality of networks, the relay communication system depends on the selected route and the amount of data passing through the route. Optimal bandwidth control is performed to minimize packet loss.

  More specifically, in the relay communication system of the present invention, both the terminal and the first and second networks use TCP / IP (Transmission Control Protocol / Internet Protocol) as a communication protocol via the relay device. We are carrying out communications. Here, the first and second networks may be networks of any access method regardless of the type such as wireless or wired.

  The route selection means of the relay device selects a packet passing through the relay device from the first and second networks according to parameters such as the protocol number, port number, and IP address of the packet, and the session information is stored in the session. Record in the information recording unit. Note that the routing information may be in any pattern, such as when route information is acquired using a general routing protocol, when a user sets rules in advance, or in both cases.

  Based on the information in the session information recording unit, the bandwidth control means of the relay device calculates and controls the permitted bandwidth for each session in communication based on the number of sessions communicating on the route and the traffic volume. To do. As this control method, the TCP session is divided into two parts between the terminal and the relay device and between the relay device and the first and second networks, thereby buffering the TCP data buffer unit and receiving window. The speed is adjusted by increasing or decreasing the size (the amount of data that can be received without delivery confirmation).

  In this way, in the relay communication system of the present invention, by performing bandwidth control by the TCP division method following the traffic on a certain route, the packet loss due to the burstiness of the TCP session is suppressed, and the optimum route is determined. Throughput can be realized. Here, the session refers to what is uniquely determined by a combination of a protocol number, an IP address, and a port number in TCP / IP communication.

  In the present invention, by adopting the configuration and operation as described above, it is possible to obtain an effect that optimum bandwidth control can be realized in units of paths.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a relay communication system according to an embodiment of the present invention. In FIG. 1, a relay communication system according to an embodiment of the present invention includes a relay device 1 that operates by program control, a storage device 2 that records information, and a terminal such as a PC (Personal Computer) or a PDA (Personal Digital Assistant). 3 and networks 100 and 200.

  In the relay communication system according to an embodiment of the present invention, the terminal 3 and the networks 100 and 200 perform two-way communication using TCP / IP (Transmission Control Protocol / Internet Protocol) as a communication protocol via the relay device 1. ing. Here, the networks 100 and 200 may be networks of any access method regardless of the type such as wireless or wired. Further, not only one terminal 3 but also a plurality of terminals 3 may be connected.

  The relay device 1 includes a route selection unit 11 and a bandwidth control unit 12, and the storage device 2 includes a session information recording unit 21 and a TCP data buffer unit 22.

  The route selection means 11 is means for holding the route information by exchanging route information with the networks 100 and 200, manual operation by the device manager, etc., and selecting the optimum route at that time. When the packet is received, the route selection unit 11 acquires the route at that time, and holds information such as the IP address, protocol number, port number, route, and last use time in the session information recording unit 21. The information held in the session information recording unit 21 is the minimum information, and other information may be held.

  The bandwidth control means 12 reads information on the route from the session information recording unit 21 and identifies the session to which the packet being processed belongs. Further, the bandwidth control means 12 reads out all other session information using the route used by the identified session, and calculates the permitted bandwidth from the information.

  Further, the bandwidth control means 12 holds the packet in the TCP data buffer unit 22 in the case of a TCP packet according to the calculated permitted bandwidth, performs a bandwidth control by dividing the TCP session, and performs a UDP (User Datagram Protocol) packet, Bandwidth control is performed by queuing for other packets.

  Incidentally, the route information holding method in the route selection means 11 and the bandwidth control by the queuing of the bandwidth control means 12 are well known to those skilled in the art and are not directly related to the present invention. A description of the configuration and operation is omitted. The storage device 2 may be arranged in the relay device 1.

  FIG. 2 is a diagram showing a configuration example of the session information recording unit 21 of FIG. In FIG. 2, the session information recording unit 21 includes an IP address number [transmission source (“xx.x.x”, “xx.x.z”,...) And a transmission destination (“y.y. y ”,“ ccc ”,...]], protocol number (“ TCP ”,...), and port number [source (“ A ”,“ C ”,. ..) and destination (“B”, “D”,...)], Route (“1”, “2”,...), And last use time (“a”, “b”,. ..)) Are held in association with each other.

  FIG. 3 is a flowchart showing the operation of the relay apparatus 1 of FIG. The operation of the relay device 1 will be described with reference to FIGS. The processing shown in FIG. 3 can also be realized by executing a program by a CPU (central processing unit) (computer) (not shown) of the relay device 1.

  The relay apparatus 1 supplies the packet arriving from the terminal 3 to the route selection unit 11, and the route selection unit 11 acquires session information from the header of the packet, and whether there is a session to which the packet belongs in the session information recording unit 21. Is confirmed (step S1 in FIG. 3). When there is no session information in the session information recording unit 21, the route selection unit 11 extracts a parameter from the packet and records it as session information in the session information recording unit 21 (step S2 in FIG. 3).

  When the route selection unit 11 finds the session information in the session information recording unit 21 or records the session information in the session information recording unit 21, the route selection unit 11 specifies the route of the session from the route information (step S3 in FIG. 3). The identified route is recorded in the session information recording unit 21. Since this process is the same as the process performed by a general router or the like, a detailed description of the means and its operation is omitted.

  When the route is specified, the bandwidth control unit 12 acquires from the session information recording unit 21 all the session information on the specified route and the packet amount held in the TCP data buffer unit 22 in each session. The permitted bandwidth is calculated from the session information (step S4 in FIG. 3).

The calculation of the permitted bandwidth is
(1) In each session of the route, the session information and the packet amount are viewed to determine whether the session is valid at that time. In the case of TCP, it is valid if the packet is buffered, and in the case of UDP or other protocols, it is valid if it is within a certain time (for example, 10 seconds) from the last use time of the session. To do.
(2) Divide the available bandwidth by the number of valid sessions to calculate the current available bandwidth. At this time, the usable bandwidth is acquired by some means (for example, given by manual setting from the device manager).
The procedure is as follows. Here, the “number of valid sessions” in (2) may be subjected to priority processing such as weighting according to the priority of the session given by some means.

  Next, if the packet is not a TCP packet (step S5 in FIG. 3), the bandwidth control means 12 performs bandwidth control according to the permitted bandwidth calculated in the processing of step S4 using a technique such as queuing. This is performed (step S7 in FIG. 3).

  If the packet is a TCP packet (step S5 in FIG. 3), the bandwidth control unit 12 holds the packet in the TCP data buffer unit 22, and performs transmission processing similar to normal TCP processing on the held packet. Is transmitted to the networks 100 and 200 (step S6 in FIG. 3). This transmission process may be any processing method as long as it conforms to the TCP protocol. At this time, the reception window size (the amount of data that can be received without confirmation of delivery) is recalculated according to the permitted bandwidth calculated in the process of step S4, and an ACK (ACKnowledgement) is transmitted to the terminal 3.

  As a result, in this embodiment, when the terminal 3 is transmitting beyond the permitted bandwidth, the reception window size is 0, so transmission suppression is performed on the terminal 3 side, and bandwidth control is performed without packet loss. Can be realized. The same operation as described above is performed when a packet arrives from the networks 100 and 200.

  As described above, in this embodiment, the route selection unit 11 of the relay device 1 determines whether the packet passing through the relay device 1 is sent to either the network 100 or 200 depending on parameters such as the protocol number, port number, and IP address of the packet. And the session information is recorded in the session information recording unit 21.

  Based on the information in the session information recording unit 21, the bandwidth control unit 12 of the relay device 1 sets the permitted bandwidth for each session in communication based on the number of sessions communicating on the route and the communication amount. Calculate and control. As a control method, the TCP session is divided into two parts between the terminal 3 and the relay apparatus 1 and between the relay apparatus 1 and the networks 100 and 200, thereby buffering the TCP data buffer unit 22 and receiving windows. Adjust the speed by increasing or decreasing the size.

  Therefore, in this embodiment, by performing bandwidth control by the TCP division method following the traffic on a certain route, it is possible to achieve the optimum throughput of that route while suppressing packet loss due to the burstiness of the TCP session. it can. Here, the session refers to a session uniquely determined by a combination of a protocol number, an IP address, and a port number in TCP / IP communication.

  That is, in this embodiment, since session information is managed for each communication path, optimal bandwidth control can be realized on a path basis. In this embodiment, since TCP is divided and processed, bandwidth control can be realized without packet loss for a TCP session.

  FIG. 4 is a block diagram showing the configuration of a relay communication system according to another embodiment of the present invention. In FIG. 4, a relay communication system according to another embodiment of the present invention includes a relay device 1-1, 1-2, a storage device 2-1, 2-2, and terminals 3-1, 3-2 connected to a network 100, The configuration is the same as that of the relay communication system according to the embodiment of the present invention shown in FIG.

  In this embodiment, since control by the TCP reception window is effective for the terminals 3-1 and 3-2 at both ends of the networks 100 and 200, bandwidth control is realized without packet loss for the TCP session. It is possible to further improve the effect of being able to.

  In each embodiment of the present invention, the case where the relay apparatuses 1, 1-1, 1-2 and the recording apparatuses 2, 2-1, 2-2 are separated is described. , 2-2 may be arranged in the relay apparatuses 1, 1-1, 1-2, respectively, but is not limited thereto.

  Further, in each embodiment of the present invention, it has been described that there is only one network on the side of the terminals 3, 3-1, 3-2, but a plurality of networks may be used. The number is not limited to one, and any number is possible.

It is a block diagram which shows the structure of the relay communication system by one Example of this invention. It is a figure which shows the structural example of the session information recording part of FIG. It is a flowchart which shows operation | movement of the relay apparatus of FIG. It is a block diagram which shows the structure of the relay communication system by the other Example of this invention.

Explanation of symbols

1,1-1,1-2 relay device 2,2-1,2-2 storage device 3,3-1,3-2 terminal
11 Route selection means
12 Band control means
21 Session information recording part
22 TCP data buffer unit 100,200 network

Claims (19)

A relay communication system in which a terminal and first and second networks perform bidirectional communication via a relay device,
The relay device selects a route selection unit that selects one of the first and second networks based on a parameter of the packet, and a packet selected for the route selected by the route selection unit. Session information recording means for storing session information determined by parameters, and for each session in communication based on the number of sessions and the amount of communication in the route based on the information of the session information recording means And a bandwidth control means for calculating and controlling the permitted bandwidth.   2. The relay communication system according to claim 1, wherein the route selection unit records the parameter of the packet passing through the time device as session information of the selected route in the session information recording unit.   3. The bidirectional communication is performed between the terminal and the first and second networks using TCP / IP (Transmission Control Protocol / Internet Protocol) as a communication protocol. Relay communication system.   The relay communication system according to claim 3, wherein the parameters include at least a protocol number, a port number, and an IP (Internet protocol) address.   In the case of a TCP (Transmission Control Protocol) packet according to the permitted bandwidth, the bandwidth control unit holds the packet in a data buffer, performs bandwidth control by dividing a TCP session, and in the case of a packet other than the TCP packet 5. The relay communication system according to claim 3, wherein bandwidth control is performed by queuing.   Dividing the TCP session between the terminal and the relay device and between the relay device and the first and second networks, buffering the TCP packet to the data buffer, and delivering the packet 6. The relay communication system according to claim 5, wherein the bandwidth control is performed by increasing or decreasing a reception window size indicating an amount of data that can be received without confirmation. A relay device that relays communication between a terminal and a first and second network when performing bidirectional communication,
A route selection unit that selects one of the first and second networks based on a parameter of the packet for a packet passing through its own device, and a route selected by the route selection unit is determined by the parameter of the packet Based on the information of the session information recording means for storing session information and the session information recording means, the permitted bandwidth is calculated for each session in communication based on the number of sessions and the amount of communication on the route. And a bandwidth control means for controlling the relay device.   8. The relay device according to claim 7, wherein the route selection unit records a parameter of a packet passing through the time unit as session information of the selected route in a session information recording unit.   9. The bidirectional communication is performed between the terminal and the first and second networks using TCP / IP (Transmission Control Protocol / Internet Protocol) as a communication protocol. Relay device.   The relay apparatus according to claim 9, wherein the parameters include at least a protocol number, a port number, and an IP (Internet protocol) address.   In the case of a TCP (Transmission Control Protocol) packet according to the permitted bandwidth, the bandwidth control unit holds the packet in a data buffer, performs bandwidth control by dividing a TCP session, and in the case of a packet other than the TCP packet 11. The relay apparatus according to claim 9, wherein bandwidth control is performed by queuing.   The TCP session is divided into two parts between the terminal and the own apparatus, and between the own apparatus and the first and second networks, and the TCP packet is buffered in the data buffer, and there is no delivery confirmation. 12. The relay apparatus according to claim 11, wherein the bandwidth control is performed by increasing / decreasing a reception window size indicating the amount of data that can be received by the network. A session-specific bandwidth control method used in a relay communication system in which a terminal and first and second networks perform bidirectional communication via a relay device,
The relay device selects a packet passing through the own device according to a parameter of the packet and selects one of the first and second networks, and the packet of each packet for each route selected by the route selection unit. Based on the information of the session information recording means for storing the session information determined by the parameters, the permitted bandwidth is calculated for each session in communication based on the number of sessions communicating and the traffic volume on the route. A bandwidth control method for each session, characterized by executing a bandwidth control process to be controlled.   14. The bandwidth control method for each session according to claim 13, wherein, in the route selection process, a parameter of a packet passing through the time device is recorded in session information recording means as session information of the selected route.   15. The bidirectional communication is performed between the terminal and the first and second networks using TCP / IP (Transmission Control Protocol / Internet Protocol) as a communication protocol. Bandwidth control method for each session.   16. The bandwidth control method for each session according to claim 15, wherein the parameters include at least a protocol number, a port number, and an IP (Internet protocol) address.   In the bandwidth control process, in the case of a TCP (Transmission Control Protocol) packet according to the permitted bandwidth, the packet is held in a data buffer, the TCP session is divided to perform bandwidth control, and the packet is other than the TCP packet. 17. The bandwidth control method for each session according to claim 15, wherein bandwidth control is performed by queuing.   Dividing the TCP session between the terminal and the relay device and between the relay device and the first and second networks, buffering the TCP packet to the data buffer, and delivering the packet 18. The bandwidth control method for each session according to claim 17, wherein the bandwidth control is performed by increasing or decreasing a reception window size indicating an amount of data that can be received without confirmation. A program executed by a relay device that relays communication between the terminal and the first and second networks when performing bidirectional communication,
In the central processing unit of the relay device, a route selection process for selecting one of the first and second networks according to the parameter of the packet, and a route selected by the route selection unit. Based on the information of the session information recording means that stores the session information determined by the parameter of the packet, the permitted bandwidth for each session in communication based on the number of sessions communicating and the traffic volume on the route A program for executing a bandwidth control process for calculating and controlling the bandwidth.

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