Device and method for optimizing ARP aging mechanism

Abstract

The invention provides a device and a method for optimizing an ARP aging mechanism. The device and the method are applied to network equipment. The method comprises the following steps: matching unmarked table entries in an ARP table with an MAC (Media Access Control) address forwarding table, and marking the table entries if the MAC addresses of the table entries have corresponding records in the MAC address forwarding table; postponing the aging time of the marked table entries in the ARP table by a predetermined duration T, and detecting the table entries when the aging time is reached; and when predetermined aging time is reached, processing the unmarked table entries in the ARP table according to a current aging rule. Through the technical scheme of the invention, the current ARP aging mechanism is effectively optimized; the running efficiency of a CPU (Central Processing Unit) is increased; and the network load is lowered.

Description

technical field [0001] The invention relates to the field of network communication, in particular to a device and method for optimizing an ARP aging mechanism. Background technique [0002] In the process of network communication, it often happens that messages are forwarded across VLANs (Virtual Local Area Networks, virtual local area networks). The so-called cross-VLAN forwarding is a type of Layer 3 forwarding. Since MAC addresses are used for layer 2 packet forwarding, and IP addresses are used for layer 3 packet forwarding, the switching device needs to resolve from IP addresses to MAC addresses based on cached ARP entries. The purpose of VLAN forwarding packets. Wherein, the ARP entry includes the MAC address and its corresponding IP address. In order to ensure the correctness of the resolution, the switching device needs to constantly delete and update the ARP entries. [0003] In the prior art, an ARP entry has an aging time, within the aging time, if an ARP respo...

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Problems solved by technology

[0004] However, at present, many network devices adopt the method of separating table entry maintenance and table entry application, such as switches, which mainly rely on chips to forward packets. In this way, the chips inside the switch will apply ARP entries. But the work of maintaining ARP entries is done by the CPU outside the chip

For this type of equipment, there are serious hidden dangers in the ARP entry aging method in the prior art: after the CPU sends the ARP entry to the chip, the packets corresponding to the entry will be forwarded by the chip, but the CPU will not After receiving the message corresponding to the entry, in this way, the entry will be deleted after the aging time, and the chip will send a large number of messages in an instant and trigger the ARP parsing process, causing the CPU load to be too heavy, which may seriously cause The CPU is paralyzed and the network link is interrupted

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