KR102219270B1 - Method for processing traffic based on sdn - Google Patents

Abstract

The SDN-based traffic processing method according to the present invention includes a process of receiving a DHCP message of a source host from an openflow switch, and in response to receiving the DHCP message, a candidate IP set including at least one IP from a DHCP server. It may include the process of obtaining and transferring the obtained candidate IP set to the openflow switch for transmission to the source host.

Description

SDN-based traffic processing method {METHOD FOR PROCESSING TRAFFIC BASED ON SDN}

The present invention relates to a technique for processing network traffic, and more particularly, an SDN suitable for reducing broadcast traffic based on a software defined network (SDN) suitable for selectively providing various additional services to communication terminals. It relates to a traffic processing method based on.

As is well known, DHCP (Dynamic Host Configuration Protocol) is a protocol that provides a function of allocating an IP address to a communication terminal such as a computer or a server, and such a function can be performed through a DHCP server.

For example, when host A wants to be assigned an IP address, host A generates a DHCP discovery packet (DHCP discovery message) and broadcasts it to all hosts in the network, thereby receiving an IP address from a DHCP server that responds. I can.

In addition, ARP (Address Resolution Protocol) is a protocol that converts a network layer address into a data link layer address, that is, a protocol that provides a function of obtaining a MAC address from an IP address.

For example, when host A wants to obtain host B's MAC address, host A responds by generating a control packet (ARP request message) called ARP request and broadcasting it to all hosts in the network (subnet). Host B's MAC address can be obtained from host B.

In other words, DHCP message and ARP message functioning as control packets for connection between hosts are representative messages that cause broadcasting traffic. These messages increase traffic in the network, increase the load of the DHCP server, and consume excessive network bandwidth. Various problems are being caused.

Republic of Korea Patent Publication No. 10-2008-0097542, published on November 6, 2008.

In the present invention, when a DHCP discovery message or an ARP request message is generated, it is not broadcast to each host, but is transmitted to the SDN controller so that the SDN controller can respond to the DHCP discovery message or the ARP request message, respectively. Suggest. According to an embodiment of the present invention, when a DHCP discovery message or an ARP request message is generated, a traffic processing method in which the SDN controller responds to the DHCP discovery message or the ARP request message by transmitting it to the SDN controller without broadcasting to each host. Suggest.

The problem to be solved by the present invention is not limited to the ones mentioned above, and another problem to be solved that is not mentioned can be clearly understood by those of ordinary skill in the art from the following descriptions. will be.

According to one aspect, the present invention provides a message receiving unit for receiving a DHCP message of a source host from an openflow switch, and an IP for obtaining a candidate IP set including at least one IP from a DHCP server when the DHCP message is received. It provides an SDN-based traffic processing apparatus including an acquisition unit and a message transmission unit for transmitting the acquired candidate IP set to the open flow switch.

According to another aspect, the present invention extracts a DHCP message from a message received from a source host and transmits it to an SDN controller, and in response to this, when a candidate IP set is received from the SDN controller, the received candidate IP set is transmitted to the source. SDN-based including an openflow switch transmitted to a host, and the SDN controller transmitting to the openflow switch after acquiring the candidate IP set including at least one IP from a DHCP server when the DHCP message is transmitted It provides a traffic handling device.

According to another aspect, the present invention provides a process of receiving a DHCP message of a source host from an openflow switch, and obtaining a candidate IP set including at least one IP from a DHCP server in response to receiving the DHCP message. Provides an SDN-based traffic processing method including a process and a process of transferring the acquired candidate IP set to the openflow switch for transmission to the source host.

According to another aspect, the present invention includes a message receiving unit for receiving an ARP request message of a source host from an open flow switch, a network DB storing network configuration information including MAC addresses of each host in a network, and the ARP request message. SDN including a response generator for generating an ARP response message including the MAC address of a destination host by searching the network DB when is received, and a message transmitter for transmitting the generated ARP response message to the openflow switch It provides a traffic processing device based on.

According to another aspect, the present invention extracts an ARP request message from a message received from a source host and transmits it to an SDN controller, and in response to this, when an ARP response message is received from the SDN controller, the received ARP response message is When the ARP request message is transmitted to the source host and the ARP request message is transmitted, the ARP response message including the MAC address of the destination host is generated through search of network configuration information and then transmitted to the openflow switch. It provides an SDN-based traffic processing apparatus including the SDN controller.

According to another aspect, the present invention includes a process of receiving an ARP request message of a source host from an openflow switch, and a process of generating an ARP response message including a MAC address of a destination host through search of network configuration information, For transmission to the source host, it provides an SDN-based traffic processing method including the process of transmitting the generated ARP response message to the open flow switch.

The present invention does not broadcast to each host when a DHCP discovery message or an ARP request message is generated, and allows the SDN controller to respond to the DHCP discovery message or ARP request message, respectively, so that traffic in the network (subnet) due to broadcasting traffic This increase can be suppressed, and an increase in the load of the DHCP server and excessive consumption of network bandwidth can be effectively prevented.

1 is a block diagram of a network system suitable for applying an SDN-based traffic processing technique according to the present invention.
2 is a block diagram of an SDN-based traffic processing apparatus according to an embodiment of the present invention.
3 is a flowchart illustrating a main process of processing DHCP traffic based on SDN according to an embodiment of the present invention.
4 is a block diagram of an SDN-based traffic processing apparatus according to another embodiment of the present invention.
5 is a flowchart illustrating a main process of processing ARP traffic based on SDN according to another embodiment of the present invention.

First, the advantages and features of the present invention, and a method of achieving them will become apparent with reference to embodiments to be described later in detail together with the accompanying drawings. Here, the present invention is not limited to the embodiments disclosed below, but may be implemented in a variety of different forms, only the present embodiments are intended to complete the disclosure of the present invention, and are common in the technical field to which the present invention pertains. Since it is provided by way of example in order to allow a person skilled in the art to clearly understand the scope of the invention, the technical scope of the invention should be defined by the claims.

In addition, in the following description of the present invention, if it is determined that a detailed description of known functions or configurations may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the technical idea described throughout the specification.

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

1 is a block diagram of a network system suitable for applying an SDN-based traffic processing technique according to the present invention.

Referring to Figure 1, the network system may include at least two servers (110, 120) and a software defined network (SDN) controller 130, etc., the server 110, for example, one open flow switch (OVS #1) and a plurality of VMs (VM1 to VM9), and the server 120 may include, for example, one open flow switch (OVS#2) and a plurality of VMs (VM10 to VMn). Here, each OpenFlow switch can be defined as, for example, a virtual switch installed in Linux.

In addition, VMs included in each server can recognize themselves as a server or a computer as a virtualized device. Each of these VMs can be defined as, for example, a host, and a DHCP discovery message (DHCP) for communication access with other hosts. A variety of messages (packets) such as a discovery packet), a DHCP request message (DHCP request packet), an ARP request message (ARP request packet), and the like may be generated.

Here, a DHCP discovery message (DHCP discovery packet) and an ARP request message (ARP request packet) may be classified as representative broadcasting traffic.

Next, each open flow switch (OVS#1, OVS#2) processes packets (messages) received from each host based on a policy for each traffic or service provided by the SDN controller 130. , For an embodiment of the present invention, a DHCP discovery message (DHCP discovery packet) is extracted from the message received from the source host (the source VM) and transmitted to the SDN controller 130, and in response thereto, from the SDN controller 130 When a candidate IP set including at least one IP is received, a function such as transmitting the received candidate IP set to a source host (a source VM) may be provided.

In addition, each open flow switch (OVS#1, OVS#2), for another embodiment of the present invention, extracts the ARP request message (ARP request packet) from the message received from the source host (the source VM), SDN controller When an ARP response message is received from the SDN controller 130 in response to the transmission to 130, a function such as transmitting the received ARP response message to the source host (the source VM) may be provided.

Meanwhile, the SDN controller 130 searches for network configuration information stored in its own network DB when a DHCP discovery message is transmitted from an open flow switch (eg, OVS#1) for an embodiment of the present invention. A function such as selecting a candidate IP set including at least one IP set and transmitting it to the open flow switch (OVS#1) may be provided. For this purpose, a configuration as shown in FIG. 2 may be provided.

2 is a block diagram of an SDN-based traffic processing apparatus according to an embodiment of the present invention, including a message receiving unit 202, a network DB 204, an IP determining unit 206, a message transmitting unit 208, etc. can do.

2, the message receiving unit 202 may provide a function such as receiving a DHCP discovery message (DHCP discovery packet) transmitted from the open flow switch (OVS#1) and transmitting it to the IP determination unit 206. have.

Here, the network DB 204 stores network configuration information including the IP of the DHCP server 210 located in the network, the MAC address of each host (each VM) in the network (subnet), and the like. Can be updated and managed in real time.

In addition, when a DHCP discovery message (DHCP discovery packet) is received through the message receiving unit 202, the IP obtaining unit 206 obtains a candidate IP set including at least one IP through communication with the DHCP server 210 And, it is possible to provide a function of transmitting the obtained candidate IP set to the message transmission unit 208.

Here, the DHCP server 210 is a server that provides a function of selecting and assigning an IP address from its list, and the IP acquisition unit 206 in the SDN controller 130 according to the present invention sends a DHCP discovery message (DHCP When requesting an IP by transmitting a discovery packet), a function such as selecting a candidate IP set including at least one IP and transmitting it to the IP obtaining unit 206 may be provided.

Next, the message transmission unit 208 may provide a function such as forwarding the candidate IP set provided from the IP acquisition unit 206 to the open flow switch (OVS#1).

Therefore, when the open flow switch (OVS#1) receives a candidate IP set including at least one IP from the message transmission unit 208 in the SDN controller 130, it will be transmitted to the source host (the source VM).

Next, a series of processes of processing a DHCP discovery message (DHCP discovery packet) through the SDN-based traffic processing apparatus according to the present embodiment having the configuration as described above will be described in detail.

3 is a flowchart illustrating a main process of processing DHCP traffic based on SDN according to an embodiment of the present invention.

3, when messages (packets) are received from a source host (source VM) in the open flow switch (OVS#1) (step 302), only DHCP discovery messages (DHCP discovery packets) are received from the received messages. After extraction, it is transferred to the SDN controller 130 (step 304).

Next, when the IP acquisition unit 206 in the SDN controller 130 receives a DHCP discovery message through the message receiving unit 202, it searches for the IP of the DHCP server 210 from the network DB 204 and then searches the DHCP server ( 210) is requested for the IP address requested by the source host (the source VM) (step 306).

In response, the DHCP server 210 selects a candidate IP set including at least one IP and transmits it to the IP determination unit 206 in the SDN controller 130, so that the SDN controller 130 obtains the candidate IP set. (Step 308).

Thereafter, the candidate IP set obtained from the DHCP server 210 is transmitted to the openflow switch (OVS#1) through the message transmitting unit 208, and as a result, the openflow switch (OVS#1) transmits the received candidate IP set. Transfer to the source host (the source VM) (step 310). That is, the source host can be assigned a desired IP address through the SDN controller rather than broadcasting to all hosts in the network.

On the other hand, the SDN controller 130, for another embodiment of the present invention, when the ARP request message is transmitted from the open flow switch (eg, OVS#1), search for network configuration information stored in its own network DB The ARP response message including the MAC address of the destination host (destination VM) can be generated and transmitted to the open flow switch (OVS#1). For this purpose, as shown in FIG. Can have a composition.

4 is a block diagram of an SDN-based traffic processing apparatus according to another embodiment of the present invention, a message receiving unit 402, a network DB 404, a response generating unit 406, a broadcasting command unit 408, and It may include a message transmission unit 410 and the like.

4, the message receiving unit 402 receives the ARP request message (ARP request packet) of the source host (departure VM) transmitted from the open flow switch (OVS#1) and delivers it to the response generation unit 406. It can provide functions such as.

Here, network configuration information including MAC addresses of each host (each VM) in the network (subnet) is stored in the network DB 404, and such network configuration information can be updated and managed in real time.

And, when the ARP request message is received from the message receiving unit 402, the response generating unit 406 searches the network DB 404 to provide an ARP response message (ARP response packet) including the MAC address of the destination host (destination VM). It is possible to provide a function such as generating and transmitting the generated ARP response message to the message transmission unit 410.

In addition, if the MAC address of the destination host (destination VM) does not exist as a result of the search of the network DB 404, the response generation unit 406 may provide a function of notifying this to the broadcasting command unit 408. have.

Next, when the broadcast command unit 408 is notified from the response generation unit 406 that the MAC address of the destination host has not been searched in the network DB 404, a command message to process the corresponding ARP request message as broadcasting May be generated and transmitted to the message transmission unit 410.

And, the message transmission unit 410 provides a function such as transmitting the ARP response message provided from the response generating unit 406 or the command message provided from the broadcasting command unit 408 to the open flow switch (OVS#1). can do.

Therefore, in the open flow switch (OVS#1), when an ARP response message (ARP response packet) including the MAC address of the destination host is received from the message transmission unit 410 in the SDN controller 130, it is sent to the source host (the source VM). When a command message is received from the message transmission unit 410, broadcasting for the corresponding ARP request message (broadcasting to all VMs in the subnet) will be processed.

Next, a series of processes of processing an ARP request message (ARP request packet) through the SDN-based traffic processing apparatus according to the present embodiment having the configuration as described above will be described in detail.

5 is a flowchart illustrating a main process of processing ARP traffic based on SDN according to another embodiment of the present invention.

5, in the open flow switch (OVS#1), when messages (packets) are received from a source host (source VM) (step 502), only ARP request messages (ARP request packets) are received from the received messages. After extraction, it is transferred to the SDN controller 130 (step 504).

In response, the response generation unit 406 in the SDN controller 130 searches the network DB 404 (step 506) to extract the MAC address of the destination host (destination VM) related to the ARP request message (step 508). ).

As a result of the extraction in step 508, if the MAC address of the destination host (destination VM) exists, the response generation unit 406 generates an ARP response message (ARP response packet) including the MAC address of the destination host. It is transmitted to the open flow switch OVS#1 through the message transmission unit 410 (step 510).

As a result, the openflow switch (OVS#1) will transmit the ARP response message (ARP response packet including the MAC address of the destination host) received from the SDN controller 130 to the source host (the source VM) (step 512).

Meanwhile, as a result of the extraction in step 508, if the MAC address of the destination host (destination VM) does not exist, the broadcasting command unit 408 generates a command message to process the ARP request message as broadcasting It is transmitted to the open flow switch OVS#1 through the transmission unit 410 (step 514).

As a result, the open flow switch (OVS#1) broadcasts the corresponding ARP request message, that is, broadcasts the corresponding ARP request message to all VMs (hosts) in the subnet (step 516).

On the other hand, the SDN-based traffic processing method according to the present invention, which has presented the embodiment as described above, can be implemented as a computer-executable code (computer program code) in a recording medium readable by a computer (or portable computer). However, the computer-readable recording medium may include all types of recording devices that store data that can be read by a computer system. Examples of such computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, and mobile app.

Further, combinations of each block in the attached block diagram and each step in the flowchart may be performed by computer program structures. Since these computer program instructions can be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, the instructions executed by the processor of the computer or other programmable data processing equipment are shown in each block or flow chart of the block diagram. Each step creates a means to perform the functions described.

In addition, computer program instructions may be stored in a computer usable or computer readable memory, etc., which may be directed to a computer or other programmable data processing equipment to implement a function in a specific manner, so that the computer is usable or computer readable. It is also possible to produce an article of manufacture in which the instructions stored in the memory contain instruction means for performing the functions described in each block of the block diagram or each step of the flowchart.

Here, the computer program instructions may be mounted on a computer or other programmable data processing equipment, so a series of operation steps are performed on a computer or other programmable data processing equipment to create a computer-executable process, It is also possible for instructions to perform programmable data processing equipment to provide steps for executing the functions described in each block of the block diagram and each step of the flowchart.

In addition, each block or each step may represent a module, segment, or part of code including at least one or more executable instructions for executing the specified logical function(s). It should also be noted that in some alternative embodiments, functions mentioned in blocks or steps may occur out of order. For example, two blocks or steps shown in succession may in fact be performed substantially simultaneously, or the blocks or steps may sometimes be performed in the reverse order depending on the corresponding function.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains, various substitutions, modifications, and changes, etc., within the scope not departing from the essential characteristics of the present invention. It will be easy to see that this is possible. That is, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain the technical idea, and the scope of the technical idea of the present invention is not limited by these embodiments.

Accordingly, the scope of protection of the present invention should be interpreted by the claims to be described later, and all technical thoughts within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

According to an embodiment of the present invention, SDN-based traffic processing in which a DHCP discovery message or an ARP request message is not broadcast to each host, but is transmitted to an SDN controller so that the SDN controller can respond to the DHCP discovery message or ARP request message, respectively. Techniques can be provided.

The present invention including such a technical configuration does not broadcast an ADHCP discovery message or an ARP request message to all hosts in the network, and allows the SDN controller to process it alone, thereby increasing traffic in the network (subnet) due to broadcasting traffic. This can be suppressed, and it is also possible to effectively prevent an increase in the load of the DHCP server and excessive consumption of network bandwidth.

130: SDN controller 202, 402: message receiver
204, 404: Network DB 206: IP acquisition unit
208, 408: message transmitter 210: DHCP server
406: response generation unit 408: broadcasting command unit

Claims (6)

In the SDN-based traffic processing method performed in a network system including a server and an SDN-based traffic processing device,
The server is a DHCP server, and the openflow switch of the DHCP server extracts a DHCP message from messages received from a source host and delivers it to the SDN-based traffic processing device;
The process of receiving, by the SDN-based traffic processing device, a DHCP message of the source host from the open flow switch,
When the SDN-based traffic processing device receives the DHCP message of the source host, the SDN-based traffic processing device sends the DHCP server searched based on the contents of the DHCP message from a network DB storing network configuration information including the IP of a DHCP server located in the network The process of requesting the IP address requested by the source host, and
A process of obtaining, by the SDN-based traffic processing device, a candidate IP set including at least one IP from the DHCP server in response to receiving the DHCP message,
The SDN-based traffic processing apparatus transfers the acquired candidate IP set to the open flow switch for transmission to the source host;
SDN-based traffic processing method comprising the step of transmitting the obtained candidate IP set to the source host by the open flow switch of the DHCP server. The method of claim 1,
The DHCP message,
DHCP discovery message
SDN-based traffic handling method. delete In the SDN-based traffic processing method performed in a network system including a server and an SDN-based traffic processing device,
A process in which the openflow switch of the server extracts an ARP request message from messages received from a source host and delivers it to the SDN-based traffic processing device;
The process of the SDN-based traffic processing device receiving the ARP request message of the source host from the open flow switch,
The SDN-based traffic processing device obtains the MAC address of the destination host through a search of a network DB in which network configuration information of the destination host located in the network is stored, and generates an ARP response message including the MAC address of the destination host. The process of doing it,
The process of the SDN-based traffic processing device transmitting the generated ARP response message to the open flow switch for transmission to the source host;
SDN-based traffic processing method comprising the step of transmitting an ARP response message including the MAC address of the destination host to the source host by the openflow switch of the server. The method of claim 4,
When the MAC address of the destination host is not found, the process of generating a command message for broadcasting the ARP request message and transmitting it to the openflow switch
SDN-based traffic processing method further comprising a. delete

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