Proxy ARP ( Address Resolution Protocol ) is a technique by which a intermediate network device like router replies to ARP request for a given IP address that is not part of local network. The router acts as a proxy for the destination device to which the host wants to communicate and provides its own MAC address as the reply. Note: Proxy ARP can help devices on a network reach remote subnets without the need to configure routing or a default gateway. Disadvantages of Proxy ARP Proxy ARP can lead to security and performance issues on the network. It poses a security risk by making the network vulnerable to ARP spoofinf attack. In attacks, malicious devices can impersonate proxies. Intercept or modify traffic between devices. It may introduce inconsistency into the network’s topology. Addressing scheme by concealing device locations and identities. Let see when and how proxy ARP is configured in Juniper by answering below questions which often comes to our mind ...
Many technologies are leveraged to achieve business objectives and values to customer, but it comes with a price of security risk associated with them. Managing those risk would be an superficial act wasting time and money unless we understand how they are configured, maintained and operated, and then understanding the terms, definitions and concept associated with those technologies becomes paramount, Then you know how to control these risk effectively and efficiently