A method and system for realizing proxy ARP based on free ARP

Abstract

The invention discloses a method for realizing proxy ARP based on gratuitous ARP, which includes the following steps: A. The access switch monitors the gratuitous ARP process of the IP host, creates and saves the host IP address information, and sends the host IP address information to the aggregation switch; B, the aggregation switch receives the host IP address information, and saves it in the host IP address information table; C, the aggregation switch detects the target in the message after receiving the ARP request message sent by the IP host Whether the IP address is in the host IP address information table, if yes, send an ARP response message to the IP host, if not, discard the ARP request message. The invention realizes the reachability detection of the target terminal in the proxy ARP.

Description

Technical field [0001] The invention relates to the field of computer data communication, in particular to a method and system for realizing proxy ARP based on free ARP. Background technique [0002] The Address Resolution Protocol (ARP) realizes that the physical address can be known through the IP address. Gratuitous ARP (Gratuitous ARP) message is a special ARP message. The sender Internet Protocol (IP) address and destination IP address carried in the message are both the local IP address. The source media access control ( The Media Access Control (MAC) address is the local MAC address, and the destination MAC address is the broadcast address. [0003] The host realizes the following functions by sending gratuitous ARP messages: (1) Determine whether the IP addresses of other hosts conflict with the IP addresses of this machine. When other hosts receive a gratuitous ARP message, if they find that the IP address in the message is the same as their own IP address, they will ret...

AI Technical Summary

Problems solved by technology

[0005] However, the proxy ARP has the following disadvantages: the device with the proxy ARP function directly sends an ARP response to the requesting end that sends the ARP request message without detecting the reachability of the target IP, so that the ARP cache table of the requesting end exists The mapping relationship between the IP address of the target terminal and the hardware address. The requester initiates communication with the target terminal based on this hardware relationship. However, because the reachability of the target IP is not detected, the target terminal may not exist, and the communication cannot be completed in the end.

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