D-Link DWS-3160-24TC DWS-3160 Series CLI Reference Guide - Page 945
their own ARP table in accordance with the sender's MAC and IP address. The format
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Page 945 highlights
DWS-3160 Series Gigabit Ethernet Unified Switch CLI Reference Guide Figure 4 Generally, the aim is to associate the attacker's or random MAC address with the IP address of another node (such as the default gateway). Any traffic meant for that IP address would be mistakenly re-directed to the node specified by the attacker. IP spoofing attack is caused by Gratuitous ARP that occurs when a host sends an ARP request to resolve its own IP address. Figure-4 shows a hacker within a LAN to initiate ARP spoofing attack. In the Gratuitous ARP packet, the "Sender protocol address" and "Target protocol address" are filled with the same source IP address itself. The "Sender H/W Address" and "Target H/W address" are filled with the same source MAC address itself. The destination MAC address is the Ethernet broadcast address (FF-FF-FF-FF-FF-FF). All nodes within the network will immediately update their own ARP table in accordance with the sender's MAC and IP address. The format of Gratuitous ARP is displayed in the following table. A common DoS attack today can be done by associating a nonexistent or any specified MAC address to the IP address of the network's default gateway. The malicious attacker only needs to broadcast one Gratuitous ARP to the network claiming it is the gateway so that the whole network operation will be turned down as all packets to the Internet will be directed to the wrong node. 941
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