KR101307803B1 - Network traffic distributed method and network system using the same - Google Patents

Abstract

The present invention relates to a network traffic distribution method and a network system using the same.

The network traffic distribution method of the present invention includes a route port having a shortest path to a root bridge, a degginated port first passing through a path from a specific link to a root bridge, and received from another bridge than a received path cost. Checking whether the bridge including the alternate port blocked because the route path cost is less than the predetermined value by checking the traffic amount of the frame; Checking whether the frame is a frame transmitted from an edge port configured to be directly connected to the bridge when the traffic amount is greater than or equal to a predetermined value; And outputting the frame to the alternate port when the frame is transmitted from an edge port.

Network, STP, RSTP, Alternate Port, Root Port, Desigant Port

Description

Network traffic distribution method and network system using the same {NETWORK TRAFFIC DISTRIBUTED METHOD AND NETWORK SYSTEM USING THE SAME}

1 is a block diagram showing an initialization step of a network system according to an embodiment of the present invention;

2 is a two-sided view showing the path formation of the network system according to an embodiment of the present invention,

3 is a diagram illustrating path formation in an extended network system according to another embodiment of the present invention;

4 illustrates a conventional path formation in an extended network system;

5 is a flowchart illustrating a network traffic distribution method according to an embodiment of the present invention.

The present invention relates to a method for distributing network traffic and a network system using the same. The present invention relates to network traffic that can distribute traffic centralization in a network by performing a path configuration using conditional selection of a specific port based on STP and RSTP routing. A distributed method and a network system using the same.

Spanning Tree Protocol (SIP) and Rapid STP (RSTP) form a spanning tree in a LAN environment in which multiple Ethernets are connected to each other. This routing protocol delivers user frames from stations to the desired destination station without infinite loops. to be. When the existing link or bridge is added or deleted, the STP and RSTP reconstruct the spanning tree, and the user's data transmission is stopped until the reconfiguration is completed. LAN reconfiguration time in STP averaged 35 seconds and maximum 50 seconds, but RSTP, the current LAN routing standard protocol, significantly reduces the time required for reconfiguration by adding state variables and using the proposal / negotiation technique in hundreds of msec. Doing.

RSTP distinguishes between the port connected to the bridge and the user, that is, the edge port connected to the station, for each port of the bridge to achieve fast reconfiguration time. In addition, the ports connected to the bridge are subdivided into four types: a root port, a delegated port, an alternate port, and a backup port. Here, the backup port is defined only when using a shared link. The root port is the port with the shortest path to the root bridge, and the desigated port is the first port that passes through the path to the root bridge on a particular link. The alternate port is a blocked port because the route path cost received from another bridge is less than the route cost received by this port. The edge port cannot be connected to other bridges, so the edge port is not considered when changing the routing path.

On the other hand, in addition to the port role, RSTP defines three port states: revocation state, learning state, and forwarding state. The discarded state is a state in which a LAN is initially started or disabled by an administrator. The learning state is a state in which routing information starts to be added to the filtering database (FDB) by the data generated at the station, and the forwarding state is a state where normal data transmission and reception are performed. In a stable topology, the root port and the delegated port are forwarded, and the alternate and backup ports are retired.

In RSTP, the alternate ports are mostly obsolete and are not used, only the root port is used for the upstream route. In other words, in a steady state with a stable routing path, a bridge port is divided into a port that is always used and a port that is not used at all. From the point of view of the links that make up the LAN, it means that some links in the LAN are intensively used for data transfer, and others are not used at all. As a result, there is a problem that the utilization efficiency of the link is inferior and the throughput of the LAN is limited at a low level.

Therefore, the present invention was devised to solve the above-mentioned problems of the prior art, and an object of the present invention is to improve LAN performance by mitigating concentration at the expense of the shortest path principle when traffic congestion becomes severe in a network. To provide a network traffic distribution method and a network system using the same.

Network traffic distribution method according to an embodiment of the present invention for achieving the above object, the root port having the shortest path to the root bridge, the degginated port passing through the path from the specific link to the root bridge for the first time Checking whether the bridge including the alternate port blocked because the route path cost received from the other bridge is less than the received path cost by checking the amount of traffic in the frame is greater than or equal to a predetermined value; Checking whether the frame is a frame transmitted from an edge port configured to be directly connected to the bridge when the traffic amount is greater than or equal to a predetermined value; And outputting the frame to the alternate port when the frame is transmitted from an edge port.

A network system according to an embodiment of the present invention for achieving the above object, the root port having the shortest path to the root bridge, the deggiated port passing through the path from the specific link to the root bridge for the first time, receiving A plurality of bridges including at least one of the alternate ports that are blocked because the route path costs received from other bridges are less than the route costs that are routed and are linked to each other; And a station that transmits and receives a frame to and from the root bridge through the bridge, wherein the bridge including the replacement port has a predetermined value or more by inspecting a traffic amount of the frame, and the edge is formed so that the frame is directly connected to the bridge. In the case of a frame transmitted from a port, the frame is output to the alternative port.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, only parts necessary for understanding the operation according to the embodiment of the present invention will be described, and the description of other parts will be omitted so as not to disturb the gist of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and the inventor is not limited to the meaning of the terms in order to describe his invention in the best way. It should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, It is to be understood that equivalents and modifications are possible.

For example, in the following description, an embodiment of the present invention is described with respect to Rapid Spanning Tree Protocol (RSTP), but it is obvious that the present invention can be applied to STP (Spanning Tree Protocol) in the same manner.

On the other hand, the present invention defines the ports on both ends of the link that is not used in RSTP as an alternate port and a digitized port. The alternate port is inactive and the delegated port is active. The present invention has a closed port due to an alternate port that is inactive in RSTP, i.e., only one of the ports on both sides of the link is inactive, and this closed port can be selectively opened according to the characteristics of the traffic. Suppose that only a bridge having an alternate port is implemented by the method proposed in the present invention, and a bridge connected with the bridge implements only RSTP. In this case, since the bridge connecting the unused link is already opened as a digitized port from the standpoint of a bridge that implements RSTP only, if a frame is input to this port, it is normally received according to the RSTP rule. On the other hand, if an alternate port is used instead of a deg- gested port, the other bridge can also be operated by converting related software.

1 is a view schematically showing the configuration of a network system according to an embodiment of the present invention.

Prior to description, each port illustrated in FIG. 1 is arbitrarily arranged and configured to describe an embodiment of the present invention, and the present invention is not limited to the number of ports or an arrangement position between the ports.

Referring to FIG. 1, in the network system of the present invention, a bridge 10 and ports formed on one side of the bridge 10, that is, a root port R, a first digitized port D1, and a second digital signal are formed. The combined port D2, the first replacement port A1 and the second replacement port A2, and the first to third edge ports e1, e2, and e3 formed on one side of the bridge 10, and the first to It comprises a first to third stations (S1, S2, S3) directly connected to the bridge 10 through the third edge port (e1, e2, e3), respectively. The solid line shows the frame transmission path according to RSTP, and the dotted line shows the frame transmission path according to the present invention.

The bridge 10 is a network connection device that enables interconnection between two local area networks (LAN), which constitute a LAN, and operates at a data link layer of an Open System Interconnection (OSI) reference model.

The root port (R) is the port with the shortest path to the root bridge with the smallest Bridge Identification (BID).

The first degginated port (D1) and the second degginated port (D2) are the first ports to pass in the path from the particular link to the root bridge.

The first alternative port A1 and the second alternative port A2 are blocked ports because the route path cost received from another bridge is less than the route cost received by this port. The first alternative port A1 and the second alternative port A2 may be opened under a certain condition when traffic of a predetermined value or more occurs at the root port R of the network.

The first to third stations S1, S2, and S3 may be personal computers (PCs) and servers connected to the bridge 10.

On the other hand, Figure 1 shows the flow of frames in the network system according to an embodiment of the present invention. In detail, FIG. 1 illustrates that the second station S2 transmits a data frame from the bridge 10 through the second edge port e2, and a destination address of the frame to be transmitted is transmitted to the filtering database. It is not registered, indicating the situation of broadcasting to all non-edge ports.

In the bridge 10 of the present invention, a root port R for going to the shortest distance to the root freeze is used for frame transmission, and the bridge 10 includes two first alternate ports A1 and one of its own ports. There is a second alternate port A2. The bridge 10 confirms that the second station S2 is not currently registered in its FDB and checks whether t1 time has elapsed since the port state changed to the most recently forwarding state. When the above two conditions are satisfied, the frame from the second station S2 may select one of the root port R, two first alternative ports A1, and a second alternative port A2 as an output port. Here, the time t1 is a time when the network system including the bridge 10 is stabilized, and may be a predetermined time after frame transmission according to the RSTP rule is made. This t1 time may be set by the system designer in consideration of system characteristics.

2 is a diagram illustrating a network system transmitting a frame through a specific alternative port when the amount of traffic exceeds a predetermined value after FDB registration is completed according to an embodiment of the present invention.

Prior to the description, since each configuration of the network system of the present invention shown in FIG. 2 has the same configuration as that shown in FIG. 1, a detailed description of the configuration will be omitted.

Referring to FIG. 2, in the network system of the present invention, the second station S2 transmits a data frame from the bridge 10 through the second edge port e2, and may receive the data frame. In FIG. 2, a destination address of a frame must be registered in the FDB and transmitted to a corresponding port. If the output port to be forwarded is the first digitized port (D1) or the second digitized port (D2), the output port is the root port (R). Only consider. Assuming that the second station S2 is registered in the FDB of the bridge 10 and that traffic of a predetermined value or more is concentrated in the root port R, the second station S2 is the root port of the bridge 10. Any one of (R), the first alternative port A1 and the second alternative port A2 can be selected as the output port. In FIG. 2, it is assumed that the first alternative port A1 is selected as the output port. In this case, the frame from the second station S2 is transmitted through the second edge port e2, the bridge 10 and the first alternative port A1 as indicated by the dotted line. On the other hand, the frame of the second station (S2), if the traffic of the root port (R) is a predetermined value or less by setting the root port (R) as an output port, as shown by the solid line second edge port (e2) Is transmitted through the bridge (10) and the root port (R).

3 is a diagram illustrating an extended form of a network system according to another exemplary embodiment of the present invention.

Prior to the description, an extended network system according to another embodiment of the present invention shows a certain number of bridges, ports, and stations, but the present invention is not limited thereto. That is, the present invention can be configured to include multiple bridges, multiple ports, and multiple stations that can be connected to each bridge. In addition, in the drawing, an edge port formed at one side of a bridge for connecting each station may be further provided.

Referring to FIG. 3, the extended network system of the present invention includes a first bridge 11, a second bridge 22, a third bridge 33, a fourth bridge 44, and a fifth bridge 55. Include.

The first bridge 11 is a root bridge, and the twelfth digitized port D12 for connecting the eleventh digitized port D11 to the third bridge 33 for connecting with the second bridge 22. ).

The second bridge 22 is directly connected to the first to third stations S1, S2 and S3, and is connected to the first bridge 11 which is an upward bridge. This second bridge 22 is connected to the twenty-second root port R22 for connecting with the eleventh digitized port D11 of the first bridge 11 and the fourth bridge 44 by an inactive link. And a twenty-second digitized port D22.

The third bridge 33 is directly connected to the fourth to sixth stations S4, S5 and S6, and is connected between the first bridge 11 and the fourth bridge 44, which are root bridges. The third bridge 33 is responsible for transmitting and receiving frames of the fourth to sixth stations S4, S5, and S6, and plays a role of relaying frames transmitted from the fourth bridge 44. To this end, the third bridge 33 is a thirty-third root port R33 for connecting to the twelfth digitized port D12 of the first bridge 11 and a thirty-third for connecting to the fourth bridge 44. It may be provided with a digitized port (D33).

The fourth bridge 44 is directly connected to the 12th to 14th stations S12, S13, and S14, and is connected to the second bridge 22 and the fifth bridge 55 by an active link, and the fifth bridge 44. 55 is connected to an inactive link. The fourth bridge 44 is responsible for transmitting and receiving frames of the twelfth to fourteenth stations S12, S13, and S14, and relays the frames transmitted from the fifth bridge 55 to the third bridge 33. Do this. For this purpose, the fourth bridge 44 is the 44th root port R44 for connecting with the 33rd digitized port D33 of the third bridge 33 and the 44th for connecting with the fifth bridge 55. And a 44 th replacement port A44 for connecting to the port 22 and the 22nd digitized port D22 of the second bridge 22.

The fifth bridge 55 is directly connected to the seventh to eleventh stations S7, S8, S9, S10 and S11, and is connected to the fourth bridge 44. The fifth bridge 55 is responsible for frame transmission and reception of the seventh to eleventh stations S7, S8, S9, S10, and S11, and is connected to the 44th daged port D44 of the fourth bridge 44. In order to include the forty-fifth root port R55.

In the figure, arrows and numbers indicated on the link side indicate the transmission direction and the transmission station number of the frame transmitted to the root bridge, respectively. Paths according to an embodiment of the present invention show the routing paths respectively by dotted lines.

In the extended network system of the present invention having the structure as described above, it is assumed that all ports are stabilized in a normal state at the time t = 0 when the LAN starts to operate, and thus, the station starts to transmit frames in the following order. lets do it. First, at the time t1, the first to tenth stations S1, S2, S3, S4, S5, S6, S7, S8, S9, and S10 immediately transmit a frame through the 54th link 54, and the time t1 elapses. After that, the twelfth station S12 is transmitted at time t2, the thirteenth station S13 is transmitted at time t3, the fourteenth station S14 is transmitted at time t4, and the eleventh station ( S11) additionally connects to the fourth bridge 44 to transmit the frame (t1 <t2 <t3 <t4 <t5). Any station can transmit to any station, but for the sake of convenience, suppose that all frames are sent to the first bridge 11 which is the root bridge. In addition, due to transmission of the first to tenth stations S1, S2, S3, S4, S5, S6, S7, S8, S9, and S10, the traffic amount of the frame is greater than a predetermined value in the fourth bridge 44. Let's assume.

By applying the present invention, traffic can be transmitted in a more distributed manner. That is, according to the present invention, if the twelfth station S12 is added at time t2 after the reconfiguration is completed and time t1 passes, the fourth bridge 44 selects and transmits the 44th root port R44 or the 44th alternative port. Can be. Since all stations currently use the 43rd link 43, the fourth bridge 44 transmits the frame in which the 12th station S12 occurs to the 42nd link 42 through the 44th replacement port A44. Similarly, the frames of the thirteenth station S13 and the fourteenth station S14 added at time t3 and t4 may select two links, and the 42nd link 42 is selected and transmitted. In addition, since the eleventh station S11 added at time t5 is a station connected through the fifth bridge 55, it transmits only to the 43rd link 43 according to the RSTP method. As a result, eight stations are virtually connected via the thirty-first link 31 and six stations are connected through the twenty-first link 21 to the first bridge 11. Here, each of the bridges can determine the load of traffic on the bridges as storage and transmission buffers. In addition, a frame transmitted from the fourth bridge 44 through the 44th replacement port A44 is directly connected to the fourth bridge 44 to achieve traffic distribution without forming an infinite loop, that is, a closed loop. It is preferable to allow only the frame of the station and not the frame relayed through the 44th digitized port D44 of the fourth bridge 44.

On the other hand, Figure 4 shows a frame transmission according to the existing RSTP.

Referring to FIG. 4, the 44th replacement port A44 is an inactive link and has a discarded state. Accordingly, the fourth bridge 44 does not transmit the frames of the twelfth through fourteenth stations S12, S13, and S14 directly connected to the fourth bridge 44 through the 44th replacement port A44. As a result, the seventh to fourteenth stations S7, S8, S9, S10, S11, including the twelfth through fourteenth stations S12, S13, and S14 added to the fourth bridge 44 at times t2, t3, and t4. The frames of S12, S13 and S14 are all transmitted to the first bridge 11 which is the root bridge using the 43rd link 43. As a result, in the case of RSTP, 11 stations are virtually connected through the 31st link 31 and 3 stations are connected through the 21st link 21.

As described above, according to the present invention, since the frame is transmitted by using an alternative port that is not used and wasted, the use efficiency of the link can be improved and the load that is concentrated to the root port can be distributed to improve the performance of the entire network. There is. In addition, the present invention does not modify all the operations of the existing RSTP protocol and does not define a new frame, so it can be used only by simple modification of software. As such, the present invention has excellent implementation convenience in that the proposed operation is implemented even if only a part of the bridges are changed in the existing bridge network.

5 is a flowchart illustrating a network traffic distribution method according to an embodiment of the present invention.

Prior to the description, the network described below has completed the registration initialization process for each station in the Bridge's Filtering Database (FDB), and after each port has completed the separation of its port state, that is, forwarding state and revocation state, In this case, it is assumed that a certain time has passed since the system has stabilized. In addition, the bridge described below includes a root port for delivering a frame to the root bridge, a degginated port for receiving a frame from another bridge, and an alternative port selectively discarded due to cost.

Referring to FIG. 5, in the network traffic distribution method of the present invention, a bridge having an alternative port first checks its traffic amount (S101).

In step S101, the bridge is a store and forward buffer, and the traffic amount may be inspected by temporarily storing the amount of frames delivered to the bridge.

Next, the bridge checks whether the traffic amount is a predetermined value or more (S102).

In the step S102, the predetermined value is a characteristic of the network system including the bridge, for example, the capacity of the bridge constituting the system, the number of ports, the characteristics of the link connecting the bridge, the setting of the system designer, each bridge It may have a fixed value and a change value arbitrarily set according to various characteristics such as the number of stations to be connected and the use time.

Next, in the step S102, if the traffic amount is more than a certain value, it is checked whether the frame currently delivered to the bridge is transmitted from the station directly connected to the bridge (S103).

In step S103, the bridge checks whether the frame is transmitted from a deggated port or a frame transmitted from an edge port to which the stations are connected to directly connect to the bridge.

Next, in step S103, when the frame is transmitted from a station directly connected to the bridge, the frame is output to an alternative port of the bridge (S104).

In step S104, when the bridge is a frame transmitted through an edge port, the bridge outputs the frame to an alternative port of the bridge. At this time, the frame is transmitted to the destroyed port of the other bridge connected to the alternate port.

On the other hand, in step S102, when the traffic amount is less than a predetermined value, the bridge outputs the frame using the root port regardless of the origin of the frame (S105).

When the bridge determines that network traffic distribution is not necessary because the amount of traffic is equal to or less than a certain value, the bridge does not distribute the traffic, and a protocol set in a network system, for example, STP (Spanning Tree Protocol) and RSPT (Rapid) Frame is delivered according to STP).

On the other hand, in the step S103, when the frame is a frame transmitted from the bridged port of the bridge, not from the directly connected station, the bridge outputs the frame using a root port (S106). ).

In the step S106, the frame transmitted through the alternate port allows only the frame of the station directly connected to the bridge in order to achieve traffic distribution without forming an infinite loop, that is, a closed loop, and the bridged port of the bridge The frames relayed through are forwarded through the root port, so that the frames relayed do not allow the use of alternate ports.

Before the step S101, when the bridge including the replacement port is to transmit the replacement port to the frame of the station directly connected through the edge port, the station is newly connected to the bridge and the FDB (Filtering Database) ) May be set to transmit the frame to the alternate port. This setting is applied when a certain amount of traffic occurs in the bridge.

In the above-described present invention, a difference occurs when a station that is not directly registered in a filtering database (FDB), which is directly connected to a bridge itself, uses a root port to transmit a frame for the first time. In RSTP, all stations must go through the root port, whereas the present invention allows the user to select either a root port or an alternate port when a new station directly connected to the bridge itself is created. However, once the selected port is no longer overturned, it is desirable. In the present invention, when the reconfiguration is performed, it is preferable to operate in the same manner as RSTP for a predetermined time (t1) for several seconds after the reconfiguration is completed and transferred to the forwarding state in order to increase stability. Do. The information divided by the root / alternative port may be lost when the station terminates the transmission and disappears from the FDB, or when the LAN environment is changed and reconfiguration occurs. In the present invention, since the value of t1 may be set by the characteristics of the system or the system designer, it is preferable not to limit it to a specific value. In the present invention, the selection of the root port / alternative port may be possible under various conditions. That is, when the amount of traffic around a specific station is greater than or equal to a certain value, the present invention can be applied to change the path through the root port to the path through the alternative port. It can be set to a fixed value or a variable value according to the characteristics of the network, the characteristics of the cable, the number of stations, the traffic capacity required by each station, the network configuration characteristics, the change of traffic over time, and the like.

Meanwhile, in the present invention, like the RSTP, the infinite loop is not formed in the forwarding state. It can be determined that an infinite loop is formed in a situation in which transmission paths of multiple stations are overlapped. However, when a routing path is selected for only one specific station, an infinite loop does not occur because it is fixed as a tree. The present invention can improve the performance of the LAN by mitigating the bias phenomenon at the expense of the shortest path principle when the traffic is heavily biased to a part of the network.

In addition, the present invention can be applied to routing in units of stations. In addition, when a virtual local area network (VLAN) is used, it is desirable to further check whether the bridge connected through the alternate port to be selected can pass through the VLAN. LANs have a hierarchical structure, and the links used in each layer usually have the same speed. In most cases, most bridges can find alternative ports with the same root and path values. Because of this feature, the present invention hardly increases the path value, which is the distance to the destination bridge, even when using a specific alternative port instead of the root port. Due to the above characteristics, the present invention can be used while coexisting with the existing bridge.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and similarities. Therefore, the scope of the present invention should not be limited by the illustrated embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

As described above, according to the network traffic distribution method of the present invention proposed by the present invention and a network system using the same, traffic can be distributed by selectively opening and closing ports according to the amount of network traffic.

Claims (8)

Root ports with the shortest path to the root bridge, degginated ports for the first time on a path from a particular link to the root bridge, alternate ports blocked because the route path cost from the other bridge is less than the incoming path cost In the bridge-based network traffic distribution method comprising: Checking whether the bridge checks a traffic amount of the frame to determine whether the bridge is equal to or greater than a predetermined value; And outputting a frame transmitted from an edge port directly connected to the bridge to the replacement port when the traffic amount is greater than or equal to a predetermined value. The method of claim 1, And outputting the frame to the root port according to a predetermined protocol when the predetermined value is less than the predetermined value. The method of claim 2, The protocol is At least one of Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP). The method of claim 1, If the frame is passed from a bridged port of the bridge, the frame further comprises outputting to the root port of the bridge. Root ports with the shortest path to the root bridge, degginated ports for the first time on a path from a particular link to the root bridge, alternate ports blocked because the route path cost from the other bridge is less than the incoming path cost A plurality of bridges including at least one of the plurality of bridges; And And a station configured to transmit and receive a frame with the root bridge through the bridge. And the bridge inspects the amount of traffic in the frame and outputs a frame transmitted from an edge port directly connected to the bridge to the replacement port when the amount of traffic exceeds a predetermined value. 6. The method of claim 5, The bridge including the alternate port Further comprising the root port and the desigated port, And outputting the frame to the root port according to a preset protocol when the traffic amount is less than or equal to a predetermined value. The method of claim 6, The protocol is Network system, characterized in that at least one of Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP). 6. The method of claim 5, The bridge is And the frame transmitted from the bridged port of the bridge outputs to the root port of the bridge.

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