3-13 Proxy ARP ConfigurationWhen configuring proxy ARP, go to these sections for information you are interested in:z Proxy ARP Overviewz Configuring Proxy ARPz Proxy ARP Configuration ExamplesProxy ARP OverviewIntroduction to Proxy ARPIf a host sends an ARP request for the MAC address of another host that actually resides on anothernetwork (but the sending host considers the requested host is on the same network according to thedestination IP address and mask), the device in between must be able to respond to the request withthe MAC address of the receiving interface to allow Layer 3 communication between the two hosts. Thisis 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 ARPenabled device reside on the same network, proxy ARP is called local proxy ARP. If not, it is calledcommon proxy ARP.z Common proxy ARP applies where the two communication parties connect to different Layer 3interfaces 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 3interface of a device, and they are not on the same broadcast domain.Work Mechanism of Common Proxy ARPFigure 3-1 Work mechanism of common proxy ARPAs shown in Figure 3-1:
