 Disadvantage of Proxy ARP include scalability as ARP resolution by a proxy is required for every device routed in this manner, and reliability as no fallback mechanism is present, and masquerading can be confusing in some environments.Proxy ARP can create DoS attacks on networks if misconfigured.For example, a misconfigured router with proxy ARP has the ability to receive packets destined for other hosts (as it gives its own MAC address in response to ARP requests for other hosts/routers), but may not have the ability to correctly forward these packets on to their final destination, thus blackholing the traffic.