KR20140051093A - Method for managing and sharing symmetric flow and asymmetric flow in duplexed network - Google Patents

Abstract

A network dualizing device according to the present invention comprises multiple network interface units which store information on a flow flowing in the network interface units when no information on the flow exists and which provide the information on the flow for a master unit when the flow accords with an asymmetric flow; and the master unit which stores the information on the flow provided by the network interface units and which provides information on an opposite flow for the network interface units when the information on the opposite flow is stored in the master unit. Therefore, the present invention enables integrated management and analysis for the asymmetric flow which has different paths for taking in and discharging packets. [Reference numerals] (210) First network interface unit; (220) Second network interface unit; (230) Third network interface unit; (240) Fourth network interface unit; (250) Master unit

Description

FIELD OF THE INVENTION [0001] The present invention relates to symmetric flows and asymmetric flows in duplexed networks,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to network duplexing and, more particularly, to an asymmetric flow in which a packet flow path to a network duplication device and a packet flow path from a network duplication device are configured differently, And more particularly to a method and apparatus for enabling flow information management and analysis.

When a network duplication is applied at a point of presence (PoP) point or an enterprise network of a communication company, a traffic flow path or an outflow path may be composed of two or more, respectively. In this case, a situation may occur in which a connection path from a remote place and a traffic generated from a node (terminal) corresponding to the management network use different paths.

As described above, when a flow of traffic generated from a remote location to a terminal and a flow of traffic generated at a terminal and directed to a remote location take different paths in the network duplication apparatus, this flow can be defined as an asymmetric flow . On the other hand, when the flow of traffic originating from a remote location to the terminal and the flow of traffic originating from the terminal to the remote location takes the same route in the network duplication apparatus, this flow can be defined as a symmetric flow.

At this time, since the flows constituting the asymmetric flows are managed in different network interface units, unified management of the flows becomes a difficult problem. This is a problem in the network redundancy environment, This makes the management difficult.

Therefore, if a unified information management method for such an asymmetric flow is provided in a redundant network having a plurality of interfaces, it is possible to provide advanced service such as service provision and QoS.

In the case of a network service provider, an enterprise network manager, and a telco operator, if a packet can be analyzed under the same conditions for packets entering all interfaces, scalability, stability (auto-load balancing) (Additional Capacity), and flexible deployment (Flexible Deployment).

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a network duplication apparatus capable of performing an integrated analysis and management of an asymmetric flow in which an inflow path and an outflow path of a packet are different.

Another object of the present invention is to provide a network duplication method capable of performing an integrated analysis and management of an asymmetric flow in which an entry route and an exit route of a packet are different from each other.

According to an aspect of the present invention, there is provided a network duplication apparatus having a master unit and a plurality of network interface units, the network duplication apparatus comprising: a storage unit configured to store information of the flow, Providing a master unit with information of the flow when it corresponds to an asymmetric flow, requesting and receiving information of the flow opposite to the flow to the master unit, and receiving the flow information from the network interface unit And a master unit for storing information of the opposite flow for the flow and providing the information of the opposite flow to the network interface unit when the information of the opposite flow is stored, The plurality of network interface units are composed of network interface cards mounted in a slot of one board, and the master unit includes a central processing unit (CPU).

Here, the network interface unit and the master unit may be configured to interface in a PCI-Express interface manner.

Here, the network duplication device may operate based on a connection-oriented protocol. In this case, when the SYN-ACK packet is received, the network interface unit corresponds to the asymmetric flow if the information of the flow to which the SYN packet corresponding to the SYN-ACK packet belongs is not stored in the network interface unit It can be recognized. At this time, when the ACK packet for the SYN-ACK packet is received, the network interface unit determines that the flow is an asymmetric flow if the information of the flow to which the SYN-ACK packet belongs is not stored in the network interface unit can do.

Here, the network duplication device may operate based on a non-connectionless protocol. At this time, the network interface unit can perceive the flow as an asymmetric flow if the flow opposite to the flow does not flow into the network interface unit for a predetermined period.

Wherein the network interface unit provides traffic information of flows corresponding to the asymmetric flow to the master unit at a traffic processing time of flows corresponding to the asymmetric flow or at a predetermined period, And to store traffic information of flows corresponding to the asymmetric flows provided from the asymmetric flows.

Here, the network interface unit may include a control interface unit for interfacing with the master unit, a network interface unit for transmitting / receiving the flow to / from the outside, a local flow header table storage unit for storing information on flows processed by the network interface unit, A traffic information storage unit for storing traffic information of the flows, and a packet analyzing unit for analyzing packets flowing through the network interface unit and generating information of the flow corresponding to the packets, When the flow corresponds to an asymmetric flow, provides the information of the flow to the master unit via the control interface unit and transmits information of the flow opposite to the flow to the master unit And storing the traffic information of the flow in the traffic information storage unit.

Here, the master unit may include a control interface unit for interfacing with the network interface unit, an asymmetric flow header table storage unit for storing information of asymmetric flows received from the network interface unit, a traffic storing traffic information of the asymmetric flows, The information of the opposite flow for the flow is stored by referring to the information of the asymmetric flow received from the network interface unit through the information storage unit and the control interface unit and if the information of the opposite flow is stored, And a control unit for providing the network interface unit with information of the opposite flow and storing the information of the flow.

According to another aspect of the present invention, there is provided a network duplication apparatus having a plurality of network interface units each including a master unit including a central processing unit (CPU) and network interface cards mounted in a slot of one board The method comprising the steps of: analyzing a flow of the network interface unit into the network interface unit; storing information of the flow when the information of the flow is not generated; The interface unit determines whether the flow corresponds to an asymmetric flow, and provides the information of the flow to the master unit when the flow is an asymmetric flow, and requests information of the flow opposite to the flow to the master unit The master unit stores information of the flow provided from the network interface unit, and the master unit checks whether information of the opposite flow for the flow is stored, so that the information of the opposite flow is stored And providing the information of the opposite flow to the network interface unit, if any.

Here, the network interface unit and the master unit may be configured to interface in a PCI-Express interface manner.

Here, the flow may be a flow according to a connection-oriented protocol. In this case, when the SYN-ACK packet is received, the network interface unit corresponds to the asymmetric flow if the information of the flow to which the SYN packet corresponding to the SYN-ACK packet belongs is not stored in the network interface unit It can be recognized. At this time, when the ACK packet for the SYN-ACK packet is received, the network interface unit determines that the flow is an asymmetric flow if the information of the flow to which the SYN-ACK packet belongs is not stored in the network interface unit can do.

Here, the flow may be a flow according to a non-connection-oriented protocol. At this time, the network interface unit can perceive the flow as an asymmetric flow if the flow opposite to the flow does not flow into the network interface unit for a predetermined period.

Here, the network duplication method may further include the step of the network interface unit providing traffic information of flows corresponding to the asymmetric flow to the master unit at a traffic processing time of the flows corresponding to the asymmetric flow or at a predetermined period . In this case, the network duplication method may further include storing the traffic information of the flows corresponding to the asymmetric flow provided from the network interface unit by the master unit.

In general, network equipment performs flow-based analysis, which is distributed through reflection of flow table, only for the traffic flowing into the interface. In such a case, it is impossible to accurately provide a flow-based analysis in a redundant or multi-path network environment.

When the clustering method for asymmetric flows using the PCIe NIC card proposed in the present invention is applied, asymmetric flows are managed integrally for a plurality of paths related to in-out, and traffic information of asymmetric flows is also managed in real time .

Therefore, using the present invention, it is possible to perform traffic analysis such as flow-based deep packet inspection, thereby enabling flow-based application recognition and control.

1 is a conceptual diagram for explaining the concept of a network duplication apparatus according to the present invention.
2 is a block diagram for explaining a configuration of an embodiment of a network duplication apparatus according to the present invention.
3 is a block diagram illustrating an exemplary configuration of a network interface unit of a network duplication apparatus according to the present invention.
4 is a block diagram for explaining a configuration example of a master unit of the network duplication apparatus according to the present invention.
5 is a conceptual diagram illustrating packet transfer between a client and a server according to a TCP protocol in order to explain operation of a connection-oriented protocol of the network duplication apparatus according to the present invention.
FIG. 6 is a message flow diagram illustrating an operation procedure for a connection-oriented protocol between elements of a network duplication apparatus according to the present invention.
7 is a conceptual diagram illustrating packet transfer between a client and a server according to a non-TCP protocol in order to explain operation of a non-connection-oriented protocol of the network duplication apparatus according to the present invention.
FIG. 8 is a message flow diagram illustrating an operation procedure for a non-connection-oriented protocol between elements of a network duplication apparatus according to the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

The terms first, second, A, B, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram for explaining the concept of a network duplication apparatus according to the present invention.

Referring to FIG. 1, the network duplication apparatus 110 provides services for packets flowing through four nodes 101, 102, 103, and 104. It is to be understood that the nodes 101 and 102 are connected to the IP backbone network 120 and the nodes 103 and 104 are connected to the subscriber access network 130. [ In the following description, it is assumed that the server 121 is located in the IP backbone network and the client 131 is located in the subscriber access network.

The interfaces 111, 112, 113 and 114 between the respective nodes 101, 102, 103 and 104 may be configured to include a plurality of strands of one-giga-lines or 10-giga-lines, Controller (NIC). That is, the network interface unit of the network duplication apparatus according to the present invention to be described later corresponds to the network interface controller responsible for the interface between each node.

The traffic flowing into the node 101 from the server 121 through the Internet line connected through the link 141 is transmitted to the client 131 using the node 103 or the node 104 where the corresponding client 131 is located. Lt; / RTI >

If the traffic of the client 131 has flowed into the node 103 through the connected line of the link 143, the traffic from the client is transferred to the node 103 by a function such as load balancing according to the network state of the session recognizing function and the processing equipment, (101) or node (102) to the server (121).

That is, if the traffic transmitted from the server 121 to the client 131 flows into the node 101 and is transmitted through the node 103, the traffic transmitted from the client to the server flows into the node 103, Or may be communicated to the server 121 via the node 102.

If the traffic from the client to the server flows from the client to the node 103 and is delivered to the server via the node 101 (i.e., the traffic from the client to the server and the traffic from the server to the client take the same path The flow from the client to the server and the flow from the server to the client can be defined as a symmetric flow.

On the other hand, if the traffic from the client to the server flows from the client to the node 103 and is delivered to the server via the node 102, the flow from the client to the server and the flow from the server to the client is asymmetric flow Can be defined.

The network duplication apparatus according to the present invention is capable of integrally managing asymmetric flow information and asymmetric flow traffic information in the duplicated network structure.

This enables network service providers, enterprise network managers, and telco operators to integrally manage flow information of flow information and flow information for asymmetric flows, and to analyze packets under the same conditions for packets entering all interfaces Function can be provided.

Asymmetry Flow  Configuration of Network Duplication Device for Management

2 is a block diagram for explaining a configuration of an embodiment of a network duplication apparatus according to the present invention.

2, a network duplication apparatus 200 according to the present invention includes a plurality of network interface units 210, 220, 230, and 240, at least one master unit 250 connected to the plurality of network interface units, As shown in FIG. For example, the network interface units 210, 220, 230, and 240 may be configured in the form of a PCI-Express network interface controller (NIC) mounted in a slot on one board And the master unit may be configured to include a main CPU 255 (e.g., an x86 CPU).

In one embodiment, the network duplication apparatus according to the present invention includes four network interface units 210, 220, 230, and 230 each having a network interface (e.g., SFP + interface: 10 Gigabit Ethernet; 211, 221, 231, And a master unit 250 including a CPU 255 connected to the network interface units. Since the main function of the master unit 250 can be implemented using the main CPU 255 without implementing the master unit in the form of a separate card, the cost required for implementation can be reduced. Thus, the network interface units and the master unit may be configured on one server board.

The network interface units and the master unit may be configured to perform mutual communication via predetermined high-speed interfaces 261, 262, 263, and 264. [ At this time, the network interface units and the master unit may communicate with each other through the interface buses of the slots in which the units are mounted.

In the network duplexer according to the present invention, the network interface units are responsible for transmitting and receiving traffic packets with the outside, analyzing packets transmitted and received through the network interface units, and storing and managing traffic information of the flows and traffic information of the flows. However, each network interface unit can not have information about the opposite flow that constitutes an asymmetric flow if the flow going through it is an asymmetric flow. Thus, the information about the asymmetric flow is managed integrally by the master unit.

3 is a block diagram illustrating an exemplary configuration of a network interface unit of a network duplication apparatus according to the present invention.

3, an exemplary configuration 300 of a network interface unit of a network duplication apparatus according to the present invention includes a control interface unit 310, a control unit 320, a local flow header table (LFHT) (330), a flow traffic information storage unit (340), and a network interface unit (350).

First, the control interface unit 310 is a component for interfacing with the master unit described above. At this time, the control interface unit 310 can communicate with the master unit through the interface buses of the slots in which the network interface units are mounted. The control interface unit may be connected to the master unit in a PCI-Express interface manner as an embodiment. The master unit may also include a control interface unit 410 corresponding to the control interface unit 310. The configuration of the master unit will be described later.

The network interface unit 350 is a component for processing a high-speed network interface such as an SFP + interface (10 Gigabit Ethernet), for example, and is a component for performing a function of a conventional NIC.

The control unit 320, the local flow header table storage unit 330, and the flow traffic information storage unit 340 correspond to the core components of the network interface unit for performing the operation of the network duplication apparatus according to the present invention.

The local flow header table storage unit 330 is a component for storing a local flow header table LFHT. The local flow header table LFHT is a component for storing information on a flow going through each network interface unit to be. The flows in which the information is recorded in the local flow header table may be both flows constituting the symmetric flow and one-side flows constituting the asymmetric flow.

The flow traffic information storage unit 340 is a component that stores traffic information of flows stored in the local flow header table storage unit. Here, the traffic information of the flow may include, for example, the number of packets of the flow, the total amount of data, the transmission rate, the number of hops, and the like. The flow traffic information storage unit 330 and the local flow header table storage unit 340 may be integrally configured according to the embodiment.

If the first flow information corresponding to the corresponding traffic packet is not generated in the LFHT, the control unit 320 generates the information of the first flow and outputs LFHT As shown in FIG.

Further, when the controller 320 recognizes that the flow opposite to the first flow (hereinafter referred to as the second flow) is processed in the network interface unit other than itself (i.e., when the first flow is recognized as belonging to the asymmetric flow) And provides the information of the first flow to the master unit 250 through the control interface unit 310. [ In addition, the control unit 320 can request and receive information of the second flow, which is the flow opposite to the first flow, to the master unit.

At this time, the method of recognizing that the control unit (the second flow) opposite to the first flow is processed in the other network interface unit may be performed in the case of the flow according to the connection-oriented protocol and the case of the flow according to the non- Can be configured differently.

The operation of the control unit 320 and the roles of the local flow header table storage unit 330 and the flow traffic information storage unit 340 will be described later with reference to concrete operation examples.

4 is a block diagram for explaining a configuration example of a master unit of the network duplication apparatus according to the present invention.

4, an exemplary configuration 400 of a master unit of a network duplication apparatus according to the present invention includes a control interface unit 410, a CPU 420, an asymmetric flow header table (AFHT) An asymmetric flow traffic information storage unit 440, and an asymmetric flow traffic information storage unit 440. [

First, the control interface unit 410 is a component for interfacing with the above-described network interface units. At this time, the control interface unit 410 may communicate with the network interface units through the interface buses of the slots in which the network interface units are mounted. The control interface unit may be connected to the network interface units described above in a PCI-Express interface manner as an embodiment.

Meanwhile, the CPU 420, the asymmetric flow header table storage unit 430, and the asymmetric flow traffic information storage unit 440 correspond to the core components of the master unit for performing the operation of the network duplication apparatus according to the present invention.

The asymmetric flow header table storage unit 430 is an element for storing the asymmetric flow header table AFHT, and the asymmetric flow header table AFHT stores information of asymmetric flows. That is, in the local flow header table of the network interface units, the symmetric flows belonging to the corresponding network interface units and the one-side flows of the asymmetric flows going through the corresponding network interface units are recorded, while the asynchronous flow header table Information about all asymmetric flows that are processed is integrated.

The asymmetric flow traffic information storage unit 440 is a component for storing traffic information of asymmetric flows stored in the asymmetric flow header table storage unit. Here, the traffic information of the asymmetric flow may include, for example, the number of packets of the corresponding asymmetric flow, the total amount of data, the transmission rate, the number of hops, and the like. The traffic information of the asymmetric flow is collected from the network interface units that process the one-way flow constituting the asymmetric flow.

The asymmetric flow traffic information storage unit 440 and the asymmetric flow header table storage unit 430 may be integrally configured according to the embodiment. The asymmetric flow traffic information storage unit 440 and the asymmetric flow header table storage unit 430 may be stored in a nonvolatile memory such as a FLASH memory or a volatile memory such as a RAM. Lt; RTI ID = 0.0 > a < / RTI > drive.

The CPU 420 receives the information about the asymmetric flow from the network interface unit and stores it in the asymmetric flow header table, and the information of the flow opposite to the one-side flow belonging to the asymmetric flow received from the network interface unit is already stored in the asymmetric flow header table If it is stored, it performs a control role of returning it to the network interface unit. That is, the CPU 420 executes the program code for performing the above-described operation.

The operations of the CPU 420 and the roles of the asymmetric flow header table storage unit 430 and the asymmetric flow traffic information storage unit 440 will be described later with reference to concrete operation examples.

Asymmetry Flow  Network redundancy method for management

Hereinafter, the operation of the network duplication apparatus according to the present invention will be described with respect to connection-oriented protocol and non-connectionless protocol, respectively. The connection-oriented protocol may include, for example, a Transfer Control Protocol (TCP), and the non-connection-oriented protocol may be a non-TCP protocol such as User Datagram Protocol (UDP) or Internet Control Message Protocol (ICMP) .

1) Operation method corresponding to connection-oriented protocol

FIG. 5 is a conceptual diagram illustrating packet transfer between a client and a server according to a TCP protocol in order to explain operation of a connection-oriented protocol of the network duplication apparatus according to the present invention. FIG. Lt; / RTI > is a message flow diagram for illustrating an operational procedure for a connection-oriented protocol between a plurality of networks.

5, the client 510 transmits a SYN (Synchronization) packet CP1 to the server 520 to request the generation of a TCP flow, and when the server 520 responds to the TCP flow generation . Of course, it is also possible to send a SYN packet from the server side to the client side to request the generation of the TCP flow.

In the TCP protocol, a party side (e.g., a server) transmits a SYN-ACK packet to a SYN packet sent from one side (e.g., a client), and an ACK packet for a SYN- By sending, a flow from the client to the server and a flow from the server to the client, two flows can be created.

In the following description, packets transmitted from the client side to the server side are denoted by CP # n, and packets transmitted from the server side to the client side are denoted by SP # n. Here, #n corresponds to a representation for designating the order of packets.

In this case, 'client' and 'server' are terms used for convenience only in order to distinguish the subject of packet transmission and reception. In the strict sense, the roles of client and server are not defined. It should be noted that the present invention is not limited thereto. For example, in the following description, the client and the server may be referred to as a first device (terminal) and a second device (terminal), respectively.

Hereinafter, the operational procedures of the network duplication apparatus according to the present invention will be described with reference to FIGS. 5 and 6. FIG.

In the following example, the flow from the client to the server (hereinafter referred to as the client flow or the "C->S" flow) is processed through the first network interface unit, but the flow from the server to the client Flow or "S- >C" flow) is processed through the third network interface unit, that is, a situation where an asymmetric flow is generated.

When the CP1 (Client Packet 1) first arrives at the first network interface unit 210 (601), the first network interface unit 210 searches its internal LFHT (Symmetric Flow Header Table) After confirming that the flow has not yet been created, a new client flow (Client Flow) 602 is added to the LFHT. That is, at this time, the LFHT of the first network interface unit stores information that the flow from the client to the server is processed through the first network interface unit. Illustratively, LFHT is represented as storing flow information in a notation such as "C- > S" (in FIG. 6, the shade of LFHT is to indicate the item currently being processed on LFHT).

At this time, since CP1 is a SYN packet, the first network interface unit determines whether SYN-ACK packet (i.e., traffic from the server to the client; SP1 to be described later) corresponding to the SYN packet is still transmitted through the first network interface unit, It is not yet known whether it will be transmitted through a network interface unit other than itself. Therefore, the first network interface unit only generates a flow corresponding to CP1 in its LFHT and does not make a separate request to the master unit 210. [

Next, when the server packet (SP1) first arrives at the third network interface unit 230 (603), the third network interface unit 230 searches its internal LFHT, and the flow corresponding to SP1 is still generated And adds a new server flow (server flow) 604 to the LFHT. That is, at this time, the information that the flow transmitted from the server to the client to the LFHT of the third network interface unit is processed through the third network interface unit is stored. Illustratively, LFHT is represented as storing flow information in a notation such as "S-> C ".

At this time, the control unit of the third interface unit requests the master unit to register the "S- > C" flow as an asymmetric flow through the control interface unit. The third network interface unit recognizes that SP1 is a SYN-ACK packet (confirms the indicator of the packet header), but recognizes that the SYN packet corresponding to the SYN-ACK packet has not been processed by the third network interface unit Since there is no information of the "C-> S" flow), it is possible to recognize that the SP1 packet corresponds to an asymmetric flow.

The master unit 210 adds the server flow ("S-> C") information received from the third network interface unit 230 to the AFHT 606 and sends the result to the control unit of the third network interface unit 230 Reply. At this time, the master unit stores together information indicating that the flow ("S- > C") is being processed in the third network interface unit in the AFHT. For example, in the AFHT of the master unit, it is recorded that the flow from the server to the client ("S-> C") is processed in the third network interface unit NIU3 (in FIG. 6, To indicate which item is being used).

At this time, if there is a record for the opposite flow ("C- >S") already in the AFHT, the master unit can notify the third network interface unit that the opposite flow is already stored in the AFHT of the master unit. In the example of Fig. 5 and Fig. 6, at this point, since the opposite flow ("C- >S") has not yet been generated in the AFHT of the master unit, the master unit notifies that the opposite flow is not stored in the master unit . On the other hand, the master unit implicitly refers to the opposite flow ("C- >S") by not explicitly responding to a query as to whether a record for the opposite flow C- > S ") is not present in the AFHT.

When the CP2 arrives (607), the control unit of the first network interface unit 210 searches the LFHT of its LFHT to confirm that there is no opposite flow ("S-> C"), Flow) is an asymmetric flow, transmits its client flow information to the master unit 210 via the control interface unit, and requests 608 the opposite flow ("S-> C") information. At this time, since the first network interface unit knows that the previous packet CP1 is a SYN packet, the fact that the opposite flow ("S- > C") is not generated in its LFHT causes the flow & Asymmetric flow.

The master unit receiving the client flow ("C- >S") information of the first network interface unit and the search request of the opposite flow from the first network interface unit adds the requested client flow information to the AFHT (609) If there is an SF, it returns the result to the corresponding AFA 221. At this time, the master unit records 609 the fact that the first network interface unit processes the client flow ("C->S") in the AFHT.

After the above-described procedures, the first network interface unit recognizes that the client flow ("C-> S") that it is processing corresponds to the asymmetric flow, and the third network interface unit also recognizes that the server flow S- > C ") corresponds to an asymmetric flow.

Therefore, in subsequent procedures, the first network interface unit continuously updates the traffic information (e.g., the number of packets, the total amount of data, the delivery rate, the number of hops, etc.) of its flow ("C-> S" , And the third network interface unit continuously updates and stores traffic information of its flow ("S- > C").

In addition, the first and third network interface units can transmit updated traffic information to the master unit at the time when packets belonging to each flow are transmitted and received. Alternatively, the first and third network interface units may transmit the traffic information of each flow to the master unit at predetermined intervals. The master unit stores the asymmetric flow traffic information received from each network interface unit in the asymmetric flow traffic information storage unit 440.

The predetermined period may be a predetermined time interval. Alternatively, the first and third network interface units may be configured to transmit traffic information of each flow to the master unit at a time when a predetermined event condition is met.

At this time, the first and third network interface units may be configured so that traffic information for flows other than an asymmetric flow is maintained only by itself and not provided to the master unit. By the above-described method, the first and third network interface units can distinguish whether the flow going through them is a symmetric flow or a flow belonging to an asymmetric flow, so that traffic information for the symmetric flow is kept only by itself, I can not.

This can reduce the communication bandwidth burden between the master unit and the network interface units. Meanwhile, the master unit integrally manages information on asymmetric flows of the network duplication apparatus to which the master unit belongs. The master unit can provide asymmetric flow information managed by an external (user / manager) request to enable integrated management.

Hereinafter, a procedure for processing flow termination in the network duplication apparatus according to the present invention will be described.

When the SPn (Fin packet) arrives (610), the third network interface unit deletes the server flow (S-> C) from its LFHT (611) and requests the master unit to terminate the server flow (612). When the master unit receives the termination request of the server flow from the third network interface unit, it deletes the server flow from the AFHT (613) and returns the result to the third network interface unit.

When the CPn (Fin packet) arrives at the first network interface unit (614), the client flow ("C-> S") is deleted from its LFHT (615) and the master unit is also requested to terminate the client flow (616). Upon receiving the termination request of the client flow from the first network interface unit, the master unit deletes the client flow from the AFHT (617) and returns the result to the first network interface unit.

As a result, at the request of the first network interface unit and the third network interface unit, the information about the asymmetric flow is deleted in the AFHT of the master unit.

2) Operation method corresponding to non-connection-oriented protocol

FIG. 7 is a conceptual diagram illustrating packet transfer between a client and a server according to a non-TCP protocol in order to explain the operation of the non-connection-oriented protocol of the network duplication apparatus according to the present invention. Is a message flow diagram for illustrating operational procedures for a non-connection oriented protocol between components of a device.

7, the client 710 and the server 720 exchange data with each other according to a non-connection-oriented protocol.

In the case of the connection-oriented protocol described above (for example, the TCP protocol), there is an explicit flow generation procedure by exchanging SYN, SYN-ACK, and ACK packets between one party and the other party. A flow is implicitly generated by sending and receiving data packets without a process, and the flow is implicitly released if there is no exchange of data packets for a predetermined period of time.

In the following description, a packet transmitted from the client side to the server side is represented by CP # n, and a packet transmitted from the server side to the client side is indicated by SP # n, as in the connection-oriented embodiment described above. Here, #n corresponds to a representation for designating the order of packets.

Hereinafter, with reference to FIGs. 7 and 8, operation procedures of the network duplication apparatus according to the present invention will be described.

In the following example, the flow from the client to the server (hereinafter referred to as the client flow or the "C->S" flow) is processed through the first network interface unit, but the flow from the server to the client Flow or "S- >C" flow) is processed through the third network interface unit, that is, a situation where an asymmetric flow is generated.

When CP1 (Client Packet) first arrives at the first network interface unit (801), the first network interface unit searches its LFHT to confirm that no flow information corresponding to CP1 is generated, and transmits a client flow "C->S") is newly added (802). In this case, the first network interface unit adds only the client flow to its LFHT once since it can not know whether the flow opposite to the flow (client flow) corresponding to CP1 (i.e., the server flow) will be introduced into the first network interface unit.

When the first server unit (SP1) first arrives at the third network interface unit (803), the third interface unit also searches its own LFHT to confirm that no flow information corresponding to SP1 has been generated and adds a server flow (" S- > C ") is newly added (804). In this case, since the third network interface unit can not yet confirm that the flow (server flow) opposite to the flow corresponding to SP1 (i.e., the client flow) has gone through the first network interface unit, do.

In the case of the non-connection-oriented protocol, unlike the case of the connection-oriented protocol of the prior art, there is no packet indicator such as a SYN packet or a SYN-ACK packet, It is impossible to judge whether or not the server flow corresponds to the asymmetric flow only by the fact that it has come to itself.

Accordingly, in the first network interface unit, a period of time during which a packet of a predetermined minimum number of packets (for example, basic 3) is transmitted / received via the first network interface unit after the CP1 packet or a predetermined timeout (805), the master unit is requested to register the client flow as an asymmetric flow in the AFHT and the opposite flow (server flow) is requested to the master unit, (806).

The master unit adds the client flow information received from the first network interface unit to the AFHT (807) and returns the result to the controller of the first network interface unit. At this time, if the information of the opposite flow (server flow) already exists in the AFHT, the master unit returns information of the opposite flow to the first network interface unit.

If the opposite flow already exists, if the master unit notifies the first network interface unit of the fact that the opposite flow exists, the first network interface unit is clearly aware that the client flow is a flow corresponding to an asymmetric flow. However, in the example of Fig. 8, since the server flow is not yet recorded in the AFHT, the master unit explicitly notifies the first network interface unit that the opposite flow (server flow) has not yet been recorded in the AFHT, It notifies the first network interface unit that the opposite flow (server flow) has not yet been recorded in the AFHT.

In addition, in the third network interface unit, a packet of a predetermined minimum number of packets (for example, basic 3) after the SP1 packet is transmitted or received via the third interface unit or during a predetermined timeout (809) a request to register the server flow ("S- > C") to the AFHT to the master unit if a packet belonging to the opposite flow (i.e., client flow) And requests information about the opposite flow ("C-> S") (809).

The master unit adds the server flow information received from the third network interface unit to the AFHT (810) and returns the result to the controller of the third network interface unit. At this time, if the information of the opposite flow (client flow) already exists in the AFHT, the master unit returns information of the opposite flow to the third network interface unit.

If the opposite flow already exists, if the master unit notifies the third network interface unit that there is an opposite flow, the third network interface unit is clearly aware that the server flow is a flow corresponding to an asymmetric flow. 8, since the client flow ("C- >S") is recorded in the AFHT, the master unit notifies the third network interface unit explicitly that the opposite flow (client flow) can do. Thus, the third network interface unit can explicitly recognize that its server flow is a flow corresponding to an asymmetric flow.

The control unit of the first network interface unit may process a certain number of packets (e.g., basic = 10) while the maximum number of packets (for example, basic = 100) is processed in the case where the opposite flow (server flow) Transmits the updated traffic information of the flow to the control unit of the master unit (e. G., 811) and sends a request message for the opposite flow information. The master unit adds the client flow traffic information received from the first network interface unit to the asymmetric flow traffic information storage unit and replies the result to the control unit of the first network interface unit. At this time, if there is an opposite flow, information about the opposite flow is returned together.

Likewise, the control unit of the third interface unit may continue to transmit a certain number of packets (e.g., basic = 10) while the maximum number of packets (e.g., basic = 100) Each time it is processed, it sends the flow of updated traffic information to the master unit (e.g., 812) and sends a request message for the opposite flow. The master unit adds the server flow traffic information received from the third network interface unit to the asymmetric flow traffic information storage unit and replies the result to the control unit of the third network interface unit. At this time, if there is an opposite flow, information about the opposite flow is returned together.

That is, the first interface unit and the third interface unit transmit traffic information of the flow to the master unit at a predetermined cycle, assuming that the flow is an asymmetric flow when the flow opposite to the flow already identified is not shown to the flow. In addition, the first interface unit and the third interface unit can receive information on the opposite flow at any time from the master unit, and when the opposite flow exists in another interface unit other than itself, It can be recognized that it belongs to the flow.

On the other hand, in the case of the non-connection-oriented protocol, the end of the flow is implicitly judged by the fact that, unlike the case of the connection-oriented protocol, each network interface unit does not allow packets belonging to the flow it is processing to flow for a predetermined time . For example, the first network interface unit judges that the client flow has ended when a packet belonging to its own flow (client flow) is not received for a predetermined time. Likewise, when the packet belonging to the flow (server flow) of the third network interface unit is not received for a predetermined time, it is judged that the server flow has ended. Hereinafter, a procedure in the case where the first network interface unit and the third network interface unit determine that their flows have ended, respectively will be described.

First, if the first network interface unit recognizes that the client flow has ended (813), it deletes (814) the client flow information in its LFHT and informs the master unit that the client flow has ended (815). When the master unit is notified of the end of the client flow from the first network interface unit, it deletes the information of the client flow from the AFHT (816) and returns the result.

In the same procedure, if the third network interface unit recognizes that the server flow has ended (817), it deletes (818) the server flow information in its LFHT and informs the master unit that the server flow has ended (819). When the master unit is informed of the end of the server flow from the third network interface unit, the master unit deletes the information of the server flow in the AFHT (820) and returns the result.

As a result, at the request of the first network interface unit and the third network interface unit, the information about the asymmetric flow is deleted in the AFHT of the master unit.

Comparing the connection-oriented and non-connection-oriented embodiments, in the case of the connection-oriented embodiment, there is an explicit flow generation procedure by the SYN / SYN-ACK / ACK message so that the network interface units are relatively early It can be confirmed whether the flow is an asymmetric flow or a symmetric flow. Also, in the case of the connection-oriented embodiment, since there is an explicit flow releasing procedure by the FIN message, the network interface units can notify the master unit by confirming whether or not the flow that it processes is relatively early.

On the other hand, in the case of the non-connection-oriented embodiment, there is no explicit flow generation procedure, so that each network interface unit can send a packet to the corresponding network interface unit when the predetermined number of packets is processed or until the predetermined timer value is completed, The asymmetric flow is determined.

However, in the case of a non-connection-oriented protocol, as in the case of the connection-oriented protocol, the NIC1 and the NIC3 can be configured such that traffic information for flows other than asymmetric flows are maintained only by itself and not provided to the master unit. By the above-described method, the NIC 1 and the NIC 3 can distinguish whether the flow going through them is a symmetric flow or a flow belonging to an asymmetric flow, so that the traffic information for the symmetric flow is kept only by itself and may not be provided to the master unit . This can reduce the communication bandwidth burden between the master unit and the network interface units. Meanwhile, the master unit integrally manages information on asymmetric flows of the network duplication apparatus to which the master unit belongs. The master unit can provide asymmetric flow information managed by an external (user / manager) request to enable integrated management.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims It can be understood that

200: Network duplication device
210, 220, 230, 240: Network interface unit
250: Master unit
300: Network interface unit
310: control interface unit 320:
330: LFHT storage unit 340: Flow traffic information storage unit
350: Network interface unit
400: master unit
410: control interface unit 420: CPU
430: AFHT storage unit
440: Asymmetric flow traffic information storage unit

Claims (18)

A network duplication apparatus having a master unit and a plurality of network interface units,
Storing information of the flow when the information of the flow introduced thereto is not generated and providing the information of the flow to the master unit when the flow corresponds to an asymmetric flow, A plurality of network interface units for requesting and receiving information of an opposite flow to the master unit; And
Storing information of the flow provided from the network interface unit and confirming whether information of the opposite flow for the flow is stored and storing information of the opposite flow in the network interface unit when the information of the opposite flow is stored Wherein the master unit comprises:
Wherein the plurality of network interface units comprise network interface cards mounted in a slot of one board, and the master unit comprises a central processing unit (CPU). The method according to claim 1,
Wherein the network duplication device operates based on a connection-oriented protocol. The method of claim 2,
When the SYN-ACK packet is received, the network interface unit recognizes that the flow corresponds to the asymmetric flow if the information of the flow to which the SYN packet corresponding to the SYN-ACK packet belongs is not stored in the network interface unit Network duplication device. The method of claim 2,
Wherein the network interface unit recognizes that the flow corresponds to an asymmetric flow when an ACK packet for a SYN-ACK packet is received, and if information of a flow to which the SYN-ACK packet belongs is not stored in the network interface unit, Duplication device. The method according to claim 1,
Wherein the network duplication device operates based on a non-connection-oriented protocol. The method of claim 5,
Wherein the network interface unit recognizes that the flow corresponds to an asymmetric flow if an opposite flow to the flow is not introduced to the network interface unit for a predetermined period. The method according to claim 1,
The network interface unit
And provides traffic information of flows corresponding to the asymmetric flow to the master unit at a traffic processing time of the flows corresponding to the asymmetric flow or at predetermined intervals. The method according to claim 1,
The network interface unit
And provides traffic information of flows corresponding to the asymmetric flow to the master unit at a traffic processing time of the flows corresponding to the asymmetric flow or at predetermined intervals. The method according to claim 1,
The network interface unit
A control interface unit for interfacing with the master unit;
A network interface unit for transmitting / receiving the flow to / from the outside;
A local flow header table storage unit for storing information on flows processed by the network interface unit;
A traffic information storage unit for storing traffic information of the flows; And
Analyzing a packet flowing through the network interface unit to generate information of the flow corresponding to the packet and storing the information in the local flow header table storage unit; The information of the flow is provided to the master unit through the control interface unit, the information of the flow opposite to the flow is requested to the master unit and received, and the traffic information of the flow is stored in the traffic information storage unit A network duplication device including a control unit. The method according to claim 1,
The master unit
A control interface unit for interfacing with the network interface unit;
An asymmetric flow header table storage unit for storing asymmetric flow information received from the network interface unit;
A traffic information storage unit for storing traffic information of the asymmetric flows; And
Wherein the network interface unit checks the information of the opposite flow for the flow by referring to the information of the asymmetric flow received from the network interface unit through the control interface unit and if the information of the opposite flow is stored, And a CPU for executing a program that provides information of the opposite flow and stores the information of the flow. 1. A method for operating a network duplicating apparatus having a plurality of network interface units each consisting of a master unit including a central processing unit (CPU) and network interface cards mounted in a slot of one board,
Analyzing the flow of the network interface unit into the network interface unit;
Storing information of the flow when the information of the flow is not generated by the network interface unit;
The network interface unit determines whether the flow corresponds to an asymmetric flow, and provides the information of the flow to the master unit when the flow is an asymmetric flow, requests information of the opposite flow for the flow to the master unit, ;
The master unit storing information of the flow provided from the network interface unit; And
Checking whether information of the opposite flow to the flow is stored in the master unit, and providing the information of the opposite flow to the network interface unit when the information of the opposite flow is stored. The method of claim 11,
Wherein the flow is a flow according to a connection-oriented protocol. The method of claim 12,
When the SYN-ACK packet is received, the network interface unit recognizes that the flow corresponds to the asymmetric flow if the information of the flow to which the SYN packet corresponding to the SYN-ACK packet belongs is not stored in the network interface unit Network redundancy method. The method of claim 12,
Wherein the network interface unit recognizes that the flow corresponds to an asymmetric flow when an ACK packet for a SYN-ACK packet is received, and if information of a flow to which the SYN-ACK packet belongs is not stored in the network interface unit, Duplication method. The method of claim 11,
Wherein the flow is a flow according to a non-connection-oriented protocol. 16. The method of claim 15,
Wherein the network interface unit recognizes that the flow corresponds to an asymmetric flow if an opposite flow to the flow is not introduced to the network interface unit for a predetermined period of time. The method of claim 11,
Further comprising the step of the network interface unit providing traffic information of flows corresponding to the asymmetric flow to the master unit at a traffic processing time of the flows corresponding to the asymmetric flow or at a predetermined period. 18. The method of claim 17,
Further comprising the step of the master unit storing traffic information of flows corresponding to the asymmetric flow provided from the network interface unit.

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