KR100542407B1 - IP address information processing method using hash key and router thereby - Google Patents

Abstract

The present invention relates to a method for processing address information using a hash key capable of managing 128-bit IPv6 next hop address information without changing or adding hardware configuration in a router device designed without considering IPv6, and a router device using the same. In addition, the present invention monitors the change of the route information, and includes neighboring node and next hop address information, and generates a 32-bit hash key from the corresponding address value by a hash algorithm, and generates information on routing from the corresponding network. It is the technical gist of the data to be transferred to the processor.

Router, hash algorithm, IPv4, IPv6, nextop, gateway

Description

IP address information processing method using hash key and router hence}             

1 is a block diagram showing the basic hardware structure of a general router device.

2 is a block diagram showing a logical configuration of a router apparatus to which the address information processing apparatus according to the present invention is applied.

3 is a flowchart sequentially illustrating a method of processing next hop address information according to the present invention.

Explanation of symbols on the main parts of the drawings

200: main processor 210: router protocol engine

220: router protocol processor 230: Linux kernel

240: forwarding table processor 300: line card

310: network processor 320: next hop table

The present invention relates to a router device, and more particularly, by processing the next hop address information of the 128-bit IPv6 using a hash key, 128-bit without changing or adding a hardware device in a network processor that does not consider IPv6 An address information processing method using a hash key capable of processing IPv6 address information, and a router device using the same.

1 illustrates a basic structure of a general router device. The router device 100 includes a main processor 101 for controlling overall router functions according to a router protocol, a different router 104, and a workstation server 105. And a plurality of line cards 102 connected to a host 106 and responsible for an external interface, enable communication between the main processor 101 and the plurality of line cards 102, and control the main processor 101. Therefore, the switch fabric 103 is configured to perform a physical connection between the plurality of line cards (102).

In the router configured as described above, the line card 102 includes a network processor NP. The network processor NP may route information from the upper main processor 101 and information about an adjacent router to forward packets. Acquire a, to configure a next hop table for managing the address information for the root table and the next hop (Nexthop) node based on the received information.

In the line card 102, when a packet enters an ingress, the next hop address information for the packet is looked up in the configured next hop table, and the output is sent to the corresponding egress. It forwards the packet, maps it to the Medium Access Control (MAC) address for the next hop address that is looked up at the output, and forwards the received packet to the destination.

Therefore, for normal routing and forwarding processing, management of address information of an adjacent node, that is, an adjacent gateway, and address information of a next hop node for a predetermined packet is required.

However, recently, IPv6 (Internet protocol version 6) has been adopted as a next generation version that quadruples 32-bit Internet Protocol version 4 (IPv4), and IPv6 extends the IP address space to 128 bits to increase the number of addresses. By increasing the width, security and network scalability are improved, requiring four times the address space compared to IPv4.

However, the existing network processor which is not considered to handle IPv6 address has fixed the frame header to 10 bytes. In addition, since the area available to the user is limited to 4 bytes, the above 16 bytes It is difficult to manage and transmit the IPv6 address information, and thus routing and forwarding to the corresponding IPv6 address becomes impossible.

Accordingly, the present invention has been proposed to solve the above-mentioned conventional problems, and an object thereof is to manage IPv6 next hop address information composed of 128 bits without changing or adding hardware configuration in a router device designed without considering IPv6. An address information processing method using a hash key and a router apparatus using the same are provided.

As a construction means for achieving the above object, the present invention comprises the steps of monitoring the change of the route information; Identifying neighbor and next hop address information from the route information monitored in the above step; Generating a 32-bit hash key from the verified address information by a hash algorithm; Generating the neighbor node and the route information using the generated hash key and transmitting the generated neighbor node and the route information to a network processor; and generating a next hop table based on the received information at the network processor; Provides information processing method.

In addition, in the next hop address information processing method according to the present invention, the step of identifying the address information is

Analyzing whether the change of route information is the generation of a new route, deletion of an existing route, or change of information of a neighbor node from the monitoring result;

Decoding the corresponding information to determine whether it is an IPv4 type or an IPv6 type;

Extracting gateway information from corresponding information when the determination result is an IPv6 type and the information type is creation of a new route or deletion of an existing route;

Extracting next hop address information from corresponding information when the determination result is an IPv6 type and the information type is information change of a neighbor node; And

If the gateway information does not exist in the information above, setting a default value to the gateway value

Characterized in that comprises a.

In addition, in the next hop address information processing method according to the present invention, generating the hash key comprises: setting a hash level value; Generating a 32-bit hash key value for the extracted gateway and next hop address information; Checking whether the generated hash key exists in a hash table; If there is a hash key generated in the hash table as a result of the check, reducing the hash level to 1/2 and repeating the hash key generation; And inserting into the hash table if the hash key generated in the hash table does not exist as a result of the check.

In addition, the present invention is another configuration means for achieving the above object, in the next hop address information processing apparatus of the router apparatus performing router processing between neighboring nodes according to a predetermined router protocol, the packet in cooperation with the router protocol A router protocol engine for exchanging route information that is routerable information and forwarding arbitrary packets to the destination router using these route information; A Linux kernel that monitors generation, deletion and modification of route information by a router protocol and provides router information in a netlink message; And a forwarding table processor extracting the next hop address or gateway address information of 128 bits from the information provided from the Linux kernel, generating a 32-bit hash key value through a hash algorithm, and generating router information using the generated key value. Characterized in that.

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

2 is a block diagram showing a router device according to the present invention. In the router device of the present invention, the main processor 200 includes a router protocol engine 210, a router protocol processor 220, and a Linux kernel ( 230, and a forwarding table processor 240.

In addition, the line card 300 includes a network processor 310 for processing the next hop address information transmitted from the forwarding table processor 240 to generate the next hop table 320.

Referring to FIG. 2, the router protocol engine 210 exchanges route information, which is information for routing packets, in cooperation with the router protocol unit 220, and forwards arbitrary packets to the destination router using these route information. To handle the function. At this time, the route information generated by the router protocol unit 220 is recorded in the router information database (RIB) 230a located in the Linux kernel 230 through the router protocol engine 210, and also the engine 210. It is stored in an internal local forwarding information database (FIB) 210a.

In addition, the forwarding engine distributes the Linux kernel's initial interface, neighbor router information, and router information as a router protocol. When a new router protocol is executed, the forwarding engine reads the kernel information and solves the cause of degrading the performance of the entire device. It will pass forwarding information locally.

When the routing protocol 220 generates the router information, the protocol engine 210 writes the route information to the kernel 230, and the Linux kernel 230 uses a forwarding table processor using a netlink device call. The change information is transmitted to 240.

Accordingly, the forwarding table processor 240 that detects the change of the route information extracts the 128-bit next hop address or gateway address information from the route information or the neighbor node information, and uses a hash algorithm to generate a 32-bit hash key. A value is generated and the key value is transmitted to the network processor 310 of the line card 300 as the next hop address information of the IPv6.

The network processor 310 of the line card 300 configures a next hop table with the received address information and performs forwarding on the input packet.

3 is a flowchart illustrating a method of processing next hop address information according to the present invention.

Referring to FIG. 3, the next hop address information processing procedure will be described as follows.

1) Monitoring change of root information and neighbor node information

When the route information generated by the router protocol 220 is sent to the router protocol engine 210, the router protocol engine 210 stores the route information in its forwarding information database 210a, and also the Linux kernel 230. In order to forward the packet forwarded to the) it is also recorded in the router information database (230a) of the Linux kernel (230).

In addition, the Linux kernel 230 notifies the forwarding table processor 240 of the route information periodically or as a netlink message when the information is changed, and receives the information from the IPv6 forwarding table processor 240 to change the route information. It will be detected (s301).

2) Function Classification by Netlink Message Type

Therefore, the forwarding table processor 240 receiving the netlink message from the Linux kernel 230 analyzes the message transmitted from the Linux kernel 230 (s302), and adds the new route information (RTM_NEWROUTE), It is checked whether one of the three kinds of deletion of the existing route information (RTM_DELETE) and change of neighbor node address information (RTM_NEWNEIGH) is applied (s303 to s305).

3) Adding new route information

As a result of the above analysis, if new route information is added, the forwarding table processor 240 decodes the protocol type from the message of the corresponding Linux kernel 230 (s306), and if it is an IPv4 type, calls the IPv4 route information processor. Then, the route information of the IPv4 type is processed (s308). Here, the processing for the IPv4 type address information is performed in the same manner as the conventional processing.

On the contrary, if the added route information is IPv6 type, it is checked whether the gateway address information exists in the corresponding route information (s310). If there is no gateway address information, the default gateway information is set and the corresponding information is transmitted to the network processor (s313). ).

In the above, if the gateway address information is included (s311), a hash level value is set as a default (s314) to convert the 128-bit address information into a 32-bit key value (s314), and then a hash algorithm is used. To generate a hash key value for the gateway address information (S315).

Then, it is checked whether the generated hash key value exists in the hash table (s316). Since the message type is a new route information addition state (s318), if the corresponding key value does not exist, the corresponding key value is inserted into the hash table. (S319). On the contrary, if it exists in the hash table, the hash level value, which is the seed value of the hash algorithm, is divided in half (s317), and then a new hash key value is generated (s315), and the generated key exists in the hash table. The process of checking whether or not is repeated (s316).

In this way, a route information addition message is generated using the last generated hash key value as route information (S321), and the generated message is transmitted to the network processor 310 of the line card 300 (S322).

4) Add / delete neighbor information

As a result of the message analysis (s302), when a new terminal is connected to or detached from the router device, if it is an addition or deletion message for the neighbor node (s305), the forwarding table processor 240 decodes the corresponding message to provide a protocol type. Whether it is IPv4 (s307),

If it is determined that the IPv4 type is performed, an IPv4 address resolution protocol (ARP) processor is called and performed (s309). If the message is an IPv6 type message, the next hop information is extracted from the received message (s312), and the 128-bit next hop address information is converted into a 32-bit key value in the same manner as the above-described route information addition. In order to set the hash level as a default value (s314), a hash key value is generated for the next hop address using a hash algorithm (s315), and it is checked whether the generated hash key value exists in the hash table (s316). .

Regardless of the attachment / detachment of the terminal, the netlink message monitored by the forwarding table processor 240 always has a RTM_NEWNEIGH message type. At this time, the RTM_NEWNEIGH messages are valid according to their state information as shown in Table 1 below. And invalid state.

division NEIGHBOR Status Information VALID STATE NUD_PERMANENT NUD_REACHABLE NUD_STALE NUD_DELAY NUD_PROBE INVALID NUD_NOARP NUD_INCOMPLETE NUD_NONE NUD_FAILED

Referring to Table 1, the valid state message corresponds to a state related to the existence of a neighbor node, and the invalid state corresponds to a state in which a neighbor node does not exist.

Referring to Table 1, it is determined whether the received message is valid or invalid (s318). If the message is in a valid state, the generated hash key is inserted into a hash table (s319). In this case, the corresponding key value is deleted from the hash table (s320).

In response to the generated hash key value, a neighbor node (Neighbor) information addition or deletion message for the next hop information is generated (S321) and transmitted to the network processor 310 of the line card 300 (S322).

5) Deleting existing route information deletion message

As a result of the analysis (s302), if the message transmitted from the Linux kernel 230 is a new route information deletion message (RTM_DELROUTE) (s304), as in the case of adding the route information, the forwarding table processor 240 is a protocol from the message. Decoding the type determines whether it is an IPv4 type (s306). If the determination result is an IPv4 type, the IPv4 route information processor is called (s308). If the determination result is the IPv6 type, it is checked whether the gateway address information exists in the route information (s310). If there is no gateway address information, the default gateway information is set and the corresponding information is transmitted to the network processor 310 (s322). If the gateway address information is included, a hash level value is set as a default to convert the 128-bit address information into a 32-bit key value (s314), and a hash key for the gateway address information using a hash algorithm. Generate a value (s315).

Then, it is checked whether the generated hash key value exists in the hash table (s316), and if present, since the message type is a new route information deletion state (s318), the corresponding key value is deleted from the hash table (s320). In operation 321, the route information deletion message is transmitted to the network processor 310 of the line card 300. However, if it does not exist in the hash table, the hash level value, which is the seed value of the hash algorithm, is divided in half (s317), and then a new hash key value is generated, and the above process is repeated.

As described above, the present invention provides a router apparatus which does not consider an IPv6 router that uses a 128-bit address in the design stage, such as an IBM network processor in developing an IPv6 router, without adding or changing hardware devices. 32-bit key value is encoded in the processing block by loading 32-bit encoded route information, which is passed from process to network process, and next hop and gateway address information for neighboring routers by using 32-bit hash algorithm. By routing the IPv6 packet by looking up the destination address for the packet and mapping it to the MAC address, it is possible to provide the IPv6 router function in the existing IPv4 router.

Claims (4)

Monitoring a change in route information; Identifying neighbor and next hop address information from the route information monitored in the above step; Generating a 32-bit hash key from the verified address information by a hash algorithm; Generating neighbor nodes and route information using the generated hash key and transmitting the neighbor node and the route information to a network processor; and Generating a next hop table based on the received information at a network processor 128-bit next hop address information processing method using a hash key comprising a The method of claim 1, wherein the checking of the neighbor node and the next hop address information comprises: Analyzing whether the change of route information is the generation of a new route, deletion of an existing route, or change of information of a neighbor node from the monitoring result; Decoding the corresponding information to determine whether it is an IPv4 type or an IPv6 type; Extracting gateway information from corresponding information when the determination result is an IPv6 type and the information type is creation of a new route or deletion of an existing route; Extracting next hop address information from corresponding information when the determination result is an IPv6 type and the information type is information change of a neighbor node; And If the gateway information does not exist in the information above, setting a default value to the gateway value 128-bit next hop address information processing method using a hash key, characterized in that comprises a. The method of claim 1, wherein generating the hash key Setting a hash level value; Generating a 32-bit hash key value for the extracted gateway and next hop address information; Checking whether the generated hash key exists in a hash table; If there is a hash key generated in the hash table as a result of the check, reducing the hash level to 1/2 and repeating the hash key generation; And Inserting into the hash table if the hash key generated in the hash table does not exist as a result of the check 128-bit next hop address information processing method using a hash key, characterized in that consisting of. In the next hop address information processing apparatus of a router apparatus that performs router processing between neighboring nodes according to a predetermined router protocol, A router protocol engine for exchanging route information, which is information for routing packets, in conjunction with a router protocol, and forwarding an arbitrary packet to a destination router using these route information; A Linux kernel that monitors generation, deletion, and change of route information by a router protocol and provides router information in a netlink message; And A forwarding table processor extracting the next hop address or gateway address information of 128 bits from the information provided from the Linux kernel, generating a 32-bit hash key value through a hash algorithm, and generating router information using the generated key value; Router device, characterized in that.

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