Method and device for arp proxy in vlan aggregation

Abstract

Embodiments of the invention provide a method of an ARP agent in VLAN polymerization and an apparatus thereof. In the method, Super VLAN equipment forwards an ARP request message sent by a first switch and starts an aging timer; according to whether to receive an ARP response message returned by a second switch in a timing length of the aging timer, whether to notify the first switch and the second switch to establish connection is determined. Because the Super VLAN equipment notifies the first switch and the second switch to establish the connection when forwarding the ARP request message of the first switch and receiving the ARP response message returned by the second switch in the timing length of the aging timer, a self port is prevented from being impacted by the message of the first switch when the second switch is waited to return the ARP response message so that network reliability is guaranteed.

Description

technical field [0001] The invention relates to the technical field of VLAN aggregation, in particular to a method and device for ARP proxy in VLAN aggregation. Background technique [0002] In traditional inter-VLAN routing, we need to configure an IP address for each VLAN as the gateway of this VLAN to achieve Layer 3 routing. In this method, each VLAN is a subnet, and the subnet number cannot be For hosts, the subnet needs to be assigned an IP address as a gateway and an IP address as a directed broadcast address. If the hosts in the VLAN do not need so many IP addresses, the remaining IP addresses in the subnet cannot be assigned to Its VLAN host uses, causing great waste. Even if variable length subnet masking (Variable Length Subnet Masking, VLSM) is used to allocate IP addresses, at least three IP addresses are wasted for each VLAN. If there are dozens or hundreds of VLANs, a large amount of IP addresses will be wasted. In this case, in order to save IP addresses, t...

AI Technical Summary

Problems solved by technology

Since two devices are in the same SUB VLAN, they only need to establish a Layer 2 connection to communicate. Therefore, when a Layer 3 connection is established through Super VLAN, Layer 3 resources are wasted and communication efficiency is reduced.

Or when establishing a layer-3 connection, when there is a MAC address protection device in the link, the connection will be interrupted, resulting in the failure of normal communication between the two devices

[0005] In addition, when two communicating devices belong to different SUB VLANs, one of the devices sends an ARP request packet to the SuperVLAN, and the Super VLAN immediately returns an ARP response packet to the device after receiving the ARP request packet. After receiving the ARP reply message, the device will send the data to be sent to the Super VLAN, but before the SuperVLAN receives the ARP reply message from another device, the Super VLAN will discard the data of the device , but its port will be continuously impacted by a large amount of data from this device, especially when another device is not found or the ARP request message is a malicious attack by a forged message, the port of the Super VLAN may be congested and cannot communicate normally. Thereby bringing security risks to the entire network

[0006] Therefore, in the prior art, when Super VLAN receives an ARP request message, it directly returns an ARP reply message to agree to establish a connection, and then forwards the ARP request message in each SUB VLAN of itself, which may result in the same VLAN If the device uses Layer 3 for communication, and the Super VLAN is waiting for a reply message, its own port will be impacted by a large number of messages, which reduces communication efficiency and cannot guarantee network reliability.

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