KR101260646B1 - Method for transferring data and network system using the same - Google Patents

Abstract

Disclosed are a data transfer method and a network system using the same. The disclosed network system includes a plurality of data transfer devices connected in the form of a dual ring topology, wherein each of the plurality of data transfer devices transfers data according to a first spanning tree protocol through a first ring topology of the dual ring topology, Data is transmitted according to a second spanning tree protocol through a second ring topology among the double ring topologies.

Description

TECHNICAL FOR TRANSFERRING DATA AND NETWORK SYSTEM USING THE SAME

Embodiments of the present invention relate to a data transfer method and a network system using the same, and more particularly, an efficient data transfer method and a network system using the same in a network system including a plurality of data transfer apparatuses connected in the form of a dual ring topology. It is about.

If a loop is formed on a network topology that transmits Ethernet packets, a packet that does not find a destination may end up in an infinite loop and waste network resources.

Therefore, it is necessary to maintain so that any two terminals can transmit and receive a frame to be one. One of the protocols for this is the Spanning Tree Protocol (STP).

More specifically, Spanning Tree Protocol detects and disables loops on network topologies and is used to provide backup links between devices.

The protocol interacts with other devices to ensure that there is a single path between any two devices in the topology, and when a loop is detected, one or more ports are blocked to remove redundant paths, i.e. It is placed in a suspended state in packet forwarding.

Furthermore, if a failure of the paths occurs in a secure spanning tree topology, the protocol can automatically reestablish the connection with the devices by changing the port state from blocking to forwarding.

The spanning tree protocol as described above is basically a protocol for preventing loops, and has a problem in that it is not suitable to be applied to a dual ring topology because all topologies are communicated by making a tree structure.

In order to solve the problems of the prior art as described above, the present invention proposes an efficient data transfer method and a network system using the same in a network system including a plurality of data transfer apparatus connected in the form of a double ring topology.

Other objects of the present invention may be derived by those skilled in the art through the following examples.

According to a preferred embodiment of the present invention to achieve the above object, it comprises a plurality of data transfer devices connected in the form of a double ring topology, each of the plurality of data transfer devices is a first ring topology of the double ring topology A network system is provided through which data is transmitted according to a first spanning tree protocol or data is transmitted according to a second spanning tree protocol through a second ring topology of the double ring topologies.

Each of the plurality of data transfer devices refers to a first port and a second port connected to a first adjacent data transfer device located counterclockwise with respect to a center point of the double ring topology shape and a center point of the double ring topology shape. And a third port and a fourth port connected to a second adjacent data transfer device located in a clockwise direction to form the first ring topology through the first port and the third port, and the second port. And the second ring topology through the fourth port.

Data transfer according to the first spanning tree protocol is performed by blocking any one of the first port and the third port of the first data transfer device among the plurality of data transfer devices, and the second spanning tree protocol. The data transfer may be performed by blocking any one of the second port and the fourth port of the second data transfer device among the plurality of data transfer devices.

The number of hops from the first data transfer device to the second data transfer device may correspond to the quotient of the total number of hops of the dual ring topology divided by two.

When the first port of the first data transfer device is blocked, the second port of the second data transfer device is blocked, and when the third port of the first data transfer device is blocked, the second data transfer. The fourth port of the device may be blocked.

Each of the plurality of data forwarding devices has a smaller cost among a path cost to a destination data delivery device according to the first spanning tree protocol and a path cost to the destination data delivery device according to the second spanning tree protocol. According to the data can be delivered to the target data transfer device.

The path cost may be the number of hops from each of the plurality of data delivery devices to the destination data delivery device.

Further, according to another embodiment of the present invention, in a data delivery method of a network system including a plurality of data transfer devices connected in the form of a double ring topology, the first ring topology of the double ring topology according to the first spanning tree protocol Creating a first data transfer path through the network; Creating a second data transfer path through a second ring topology of the dual ring topologies according to a second spanning tree protocol; And transferring data using one of the first data transmission path and the second data transmission path.

In the transferring of the data, data may be delivered using a data transfer path having a smaller number of hops to the destination data transfer device among the first data transfer path and the second data transfer path.

According to the present invention, an efficient data transfer is possible in a network system including a plurality of data transfer devices connected in a dual ring topology.

1 is a diagram schematically illustrating a network system according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a virtual LAN configured on a network system of a dual ring topology and a spanning tree protocol operated in each virtual LAN.
3 is a diagram illustrating a spanning tree protocol operated in each virtual LAN when a link failure occurs in a network system according to an embodiment of the present invention.
4 is a flowchart illustrating the overall flow of a data transfer method of a network system including a plurality of data transfer devices connected in a dual ring topology according to an embodiment of 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.

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

1 is a diagram schematically illustrating a network system according to an embodiment of the present invention.

Prior to the description, since each port shown in Figure 1 is arbitrarily arranged and configured in order to explain the embodiment of the present invention, the present invention is not limited to the number of ports or arrangement positions between the ports.

As shown in FIG. 1, the network system according to the present invention has a dual ring topology and may include, for example, four data transfer devices 100, 200, 300, and 400.

The network may be, for example, an Ethernet based network.

The data transmission apparatuses 100 to 400 are communication network connection devices for connecting two local area networks (LAN), which constitute a network, to be interconnected, and may be, for example, bridges. In the present invention, for convenience of description, it will be described assuming that the data transfer device (100 to 400) according to an embodiment of the present invention is a bridge.

Each bridge 100-400 may include four ports 102, 104, 106, 108, 202, 204, 206, 208, 302, 304, 306, 308, 402, 404, 406, 408, Ports 102, 104, 106, 108, 202, 204, 206, 208, 302, 304, 306, 308, 402, 404, 406, 408 are each bridges 100-400 disposed in a network in the form of a dual ring topology. ) May be connected to a link connecting each other.

That is, the ports 102, 104, 202, 204, 302, 304, 402, and 404 of each bridge 100 to 400 are connected to the bridge located counterclockwise of the bridge with respect to the center point of the double ring topology shape. Ports 106, 108, 206, 208, 306, 308, 406, and 408 of each bridge 100 to 400 may be connected to the bridges 100 to 400 located in the clockwise direction of the corresponding bridge.

The dotted line represents the packet transmission path according to the Spanning Tree Protocol. Hereinafter, an embodiment of the present invention will be described assuming that it is applied to a spanning tree protocol, but it is obvious that an embodiment of the present invention can be applied to a rapid spanning tree protocol (RSTP) in the same manner.

In order to form the spanning tree, all the bridges 100 to 400 that are involved in the operation of the spanning tree protocol exchange information with each other through a bridge protocol data unit (BPDU) message which is a spanning tree configuration message.

That is, by exchanging BPDUs between the bridges 100 to 400, information about a link in the network and each bridge 100 to 400 may be obtained, and the spanning tree protocol may operate based on the information.

In addition, through the BPDUs exchanged with each other, each bridge (100 to 400) can determine which ports to disable (disable). In IEEE 802.1D, a disabled port is defined as a blocking state, and an enabled port is defined as a forwarding state.

Meanwhile, the BPDU message includes a root ID, a root path cost, a transmission bridge ID, and the like, and the BPDU according to an embodiment of the present invention may further include information for identifying a topology type of a network system. In that the network system according to the present invention relates to a plurality of data transfer devices 100 to 400 connected in the form of a dual ring topology, the BPDU may preferably further include information for identifying the dual ring topology.

According to an embodiment of the present invention, two virtual LANs (VLANs) are configured for a dual ring topology, and a Spanning Tree Protocol (PVSTP) may be operated for each virtual LAN. Hereinafter, a data transmission path in a network system according to the present invention will be described in detail with reference to FIG. 2.

FIG. 2 is a diagram illustrating a virtual LAN configured on a network system of a dual ring topology and a spanning tree protocol operated in each virtual LAN.

A VLAN is a logical network that organizes physically separated LANs into workgroups within a dynamic organization, enabling efficient control of broadcast packets.

In the network system according to an embodiment of the present invention, as shown in FIG. 2, the VLAN having a low ID may be set to VLAN1 and the remaining ports to VLAN2.

That is, at each bridge 100-400, ports 102, 106, 202, 206, 302, 306, 402, 406 are connected to VLAN1, and ports 104, 108, 204, 208, 304, 308, 404 408 may be connected to VLAN2.

The spanning tree protocol operating in VLAN1 may be defined as PVSTP1, and the spanning tree protocol operating in VLAN2 may be defined as PVSTP2.

According to an embodiment of the present invention, each bridge 100 to 400 in PVSTP1 selects the bridge having the smallest bridge ID (BID) among the bridges 100 to 400 as the root bridge based on the BPDU. That is, the bridge 100 having the bridge ID of 1 may be the root bridge.

In addition, the bridge 400 separated from the root bridge 100 by the number corresponding to the quotient of the total hop count of the ring topology divided by two may block the port 402 having the low port ID among its ports 402 and 406. Can be.

According to an embodiment of the present invention, since the total number of hops in the dual ring topology is 4, the bridge 400 that is two hops away from the root bridge 100 blocks the lower port ID among its ports according to the following equation. .

Where m is the total number of hops in the dual ring topology, and q is the number of hops from the root bridge, respectively.

As another example, even when the total number of hops in the dual ring topology is 5, q is 2 according to Equation 1, so that a bridge 2 hops away from the root bridge may set a lower port ID among its ports as a blocking port.

By the setting of this blocking port, a spanning tree in VLAN1 can be configured, and loop occurrence can be prevented.

Subsequently, according to one embodiment of the present invention, in PVSTP2, the root bridge 100 may configure a spanning tree by setting a port 104 having a low port ID as a blocking port.

Meanwhile, in the present invention, each of the bridges 400 and 100 in PVSTP1 and PVSTP2 blocks a port having a low port ID among its own ports, but the present invention is not limited thereto. May set a port having a higher port ID among its ports as a blocking port.

That is, in PVSTP1, the bridge 400 may block a port 406 with a high port ID among its ports 402, 406, and in PVSTP2 the bridge 100 may have a high among its ports 104, 108. The port 108 of the ID may be blocked.

According to the spanning tree protocols in PVSTP1 and PVSTP2 operated as described above, each of the bridges 100 to 400 according to an embodiment of the present invention may generate information about a transmission path.

That is, based on the BPDU message exchange between the bridges 100 to 400, each of the bridges 100 to 400 may generate information about a forwarding path, where the information about the forwarding path is related to a path cost. May contain information.

The following tables show the routing table as an example of the information about the propagation paths generated in each bridge 100 to 400 in order.

Table 1 is a routing table generated in the bridge 100, Table 2 is a routing table generated in the bridge 200, Table 3 is a routing table generated in the bridge 300, Table 4 is a routing table generated in the bridge 400 Represent each table. Here, Linked Bridge ID is a bridge ID that can be accessed through a corresponding port of each bridge (100 to 400), Linked Port ID is the port ID of the Linked Bridge, Path Cost is the number of hops with the corresponding Linked Bridge, Blocked is the corresponding It means whether the path to the Linked Bridge is blocked.

By using the routing table as shown in Table 1 to Table 4, the plurality of bridges (100 to 400) of the network system according to an embodiment of the present invention can efficiently transfer data.

More specifically, each of the plurality of bridges 100 to 400 has a lower path cost among VLAN1 and VLAN2 to which it belongs, and transfers data to an unblocked port, thereby efficiently transferring data and preventing occurrence of a loop. It has an advantage that can be prevented.

In addition, when the path costs of VLAN1 and VLAN2 are the same, the plurality of bridges 100 to 400 according to an embodiment of the present invention may transfer data through VLAN1 previously set up as a virtual LAN.

For example, bridge 100 with bridge ID 1 is an unblocked path in passing data to bridge ID 2 (except PORT ID 2, 3 of its ports), and at VLAN1. Data can be transferred to the path through the low-hop VLAN1 (PORT ID 1) of the path (hop number 1) and the path in VLAN 2 (hop number 3).

Also, in passing data to Bridge ID 3 (Linked Bridge ID 3), it is an unblocked path (except for PORT ID 1 and 2 of its ports), the path in VLAN1 (hop count 1) and the path in VLAN2 ( Since the hop count of 1) is the same, data can be delivered to the path through VLAN1 (PORT ID 3).

Similarly, in passing data to Bridge ID 4 (Linked Bridge ID 4), it is an unblocked path (except for PORT IDs 2 and 3 of its ports), the path in VLAN1 (hops 2) and the path in VLAN2 ( Since hop counts of hops 2) are the same, data can be delivered to a path through VLAN1 (PORT ID 1).

Meanwhile, when some connection is lost in the network system, the spanning tree protocol may provide an alternative path. Hereinafter, the data transmission path of the network system according to the present invention will be described in detail with reference to FIG. 3.

3 is a diagram illustrating a spanning tree protocol operated in each virtual LAN when a link failure occurs in a network system according to an embodiment of the present invention.

As shown in FIG. 3, when a link fails in a dual ring network, the logically blocked link may be physically failed and moved to the blocked link, thereby ensuring continuous connection of the bridge.

More specifically, in the event of a failure in the link for VLAN2 between bridge 100 and bridge 300, bridge 100 unblocks the blocked port 104 as a spanning tree configuration of PVSTP2, thereby continuing the To ensure connectivity.

To this end, each of the bridges 100 and 300 of the failed link broadcasts a link disconnection BPDU message that further includes information about the ports 108 and 304 of the bridge that are disconnected through the ports 104 and 308 toward the other bridge. Can cast

Each bridge 100 to 400 that receives the link disconnection BPDU message stops packet forwarding and updates its information about its data forwarding path, ie the routing table, based on the received link disconnection BPDU message.

In this case, when each of the bridges 100 and 300 of the failed link receives the link disconnection BPDU transmitted from the other bridge, broadcasting of the link disconnection BPDU is terminated.

The following tables show the updated routing table at each bridge 100-400 in order.

Through the above process, the network system according to the present invention can ensure the continuous connection of the bridges 100 to 400 and can also prevent the occurrence of loops at the same time.

On the other hand, when all of the failed links in the network are restored, the blocking resulting from the occurrence of the failure is eliminated and each bridge 100 to 400 resets logical blocking.

When resetting logical blocking, all bridges 100 to 400 need to generate information about the new forwarding path since the information about the forwarding path previously used is no longer valid.

Accordingly, all the bridges 100 to 400 may erase the contents of each updated routing table and then create a new routing table based on the BPDU message flowing into the bridge.

4 is a flowchart illustrating the overall flow of a data transfer method of a network system including a plurality of data transfer devices connected in a dual ring topology according to an embodiment of the present invention.

As shown in FIG. 4, the data transmission method of the network system according to an embodiment of the present invention may include generating a first data transmission path (S410), generating a second data transmission path (S420), and data. It includes the step of transmitting (S430).

In step S410 according to an embodiment of the present invention, a first data transfer path is generated through a first ring topology of the double ring topologies according to a first spanning tree protocol.

In operation S420, the second data transmission path is generated through the second ring topology of the double ring topology according to the second spanning tree protocol.

In this case, the first ring topology and the second ring topology according to an embodiment of the present invention may mean two virtual LANs set on a network system having a double ring topology.

That is, the first data transmission path and the second data transmission path generated in steps S410 and S420 may be paths generated according to spanning tree protocols operated in two virtual LANs, respectively.

In step S430 according to an embodiment of the present invention, data is transmitted using one of the first data transmission path and the second data transmission path.

In this case, in operation S430, data may be transmitted using a data transfer path having a smaller number of hops to the target data transfer device among the first data transfer path and the second data transfer path.

As described above, according to the present invention, in a network system including a plurality of data transfer apparatuses connected in a dual ring topology, there is an advantage in that data can be efficiently transferred and a loop can be prevented.

So far, embodiments of the data transfer method of the network system according to the present invention have been described, and the configuration of the network system described above with reference to FIGS. 1 to 3 is applicable to the present embodiment as it is, and thus a detailed description thereof will be omitted. Let's do it.

In addition, embodiments of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Examples of program instructions, such as magneto-optical and ROM, RAM, flash memory and the like, can be executed by a computer using an interpreter or the like, as well as machine code, Includes a high-level language code. The hardware device described above may be configured to operate as at least one software module to perform the operations of one embodiment of the present invention, and vice versa.

In the present invention as described above has been described by the specific embodiments, such as specific components and limited embodiments and drawings, but this is provided to help a more general understanding of the present invention, the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations are possible from these descriptions. Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

100, 200, 300, 400: multiple data transfer devices
102, 104, 106, 108, 202, 204, 206, 208, 302, 304, 306, 308, 402, 404, 406, 408: Multiple ports

Claims (9)

Includes; a plurality of data transfer devices connected in the form of a double ring topology,
Each of the plurality of data transfer apparatuses transmits data according to a first spanning tree protocol through a first ring topology of the double ring topology, or according to a second spanning tree protocol through a second ring topology of the dual ring topologies. Pass data,
A first port and a second port connected to a first adjacent data transfer device located counterclockwise with respect to the center point of the double ring topology shape, and a second port located clockwise with respect to the center point of the double ring topology shape A third port and a fourth port connected to an adjacent data transfer device, wherein the first ring topology is formed through the first port and the third port, and through the second port and the fourth port; Forming a second ring topology. delete The method of claim 1,
Data transfer according to the first spanning tree protocol is performed by blocking any one of the first port and the third port of the first data transfer device among the plurality of data transfer devices, and the second spanning tree protocol. The data transfer according to claim 1, wherein any one of the second port and the fourth port of the second data transfer device of the plurality of data transfer devices is performed by blocking. The method of claim 3,
And the number of hops from the first data transfer device to the second data transfer device corresponds to the quotient of the total number of hops in the dual ring topology divided by two. The method of claim 3,
When the first port of the first data transfer device is blocked, the second port of the second data transfer device is blocked, and when the third port of the first data transfer device is blocked, the second data transfer. The fourth port of the device is blocked. Includes; a plurality of data transfer devices connected in the form of a double ring topology,
Each of the plurality of data transfer apparatuses transmits data according to a first spanning tree protocol through a first ring topology of the double ring topology, or according to a second spanning tree protocol through a second ring topology of the dual ring topologies. Pass data,
Delivering the data to the destination data according to the spanning tree protocol having a smaller cost between the path cost to the destination data delivery device according to the first spanning tree protocol and the path cost to the destination data delivery device according to the second spanning tree protocol. Network system, characterized in that the transmission to the device. The method according to claim 6,
The route cost is the number of hops from each of the plurality of data transfer devices to a destination data transfer device. In the data transfer method of a network system including a plurality of data transfer devices connected in the form of a double ring topology,
Generating a first data transfer path through a first ring topology of the dual ring topologies according to a first spanning tree protocol;
Creating a second data transfer path through a second ring topology of the dual ring topologies according to a second spanning tree protocol; And
Delivering data using one of the first data transmission path and the second data transmission path;
Data delivery method of the network system comprising a. 9. The method of claim 8,
The transferring of data may include transferring data using a data transfer path having a smaller number of hops to a target data transfer device among the first data transfer path and the second data transfer path. .

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