In the Man-in-the-Middle attack, the hacker eavesdrops on the communication between two parties. The individual then impersonates another person and makes the data transmission look normal for the other parties. The intent is to alter the data, steal personal information, or get login credentials for sabotaging communication.
These are a few ways to prevent a MITM attack:
Public key pair based authentication
Virtual private network
Strong router login credentials
Implement a well-built Intrusion Detection Systems (IDS) like firewalls.
Strong WEP/WPA encryption on access points
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