H3C Technologies H3C S3600 Series Switches - Manual (Page 614)

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Proxy ARP Configuration
When configuring proxy ARP, go to these sections for information you are interested in:
z Proxy ARP Overview
z Configuring Proxy ARP
z Proxy ARP Configuration Examples
Proxy ARP Overview
Introduction to Proxy ARP
If a host sends an ARP request for the MAC address of another host that actually resides on another
network (but the sending host considers the requested host is on the same network according to the
destination IP address and mask), the device in between must be able to respond to the request with
the MAC address of the receiving interface to allow Layer 3 communication between the two hosts. This
is achieved by proxy ARP. Proxy ARP hides the physical details of the network.
If the target IP address in an incoming ARP request and the receiving interface of the proxy ARP
enabled device reside on the same network, proxy ARP is called local proxy ARP. If not, it is called
common proxy ARP.
z Common proxy ARP applies where the two communication parties connect to different Layer 3
interfaces of a device, and they are not on the same broadcast domain.
z Local proxy ARP applies where the two communication parties connect to the same Layer 3
interface of a device, and they are not on the same broadcast domain.
Work Mechanism of Common Proxy ARP
Figure 3-1 Work mechanism of common proxy ARP
As shown in Figure 3-1 :