HOW CAN ATTACKER ATTACK NETWORK?
1.Network Sniffing -> Alice is talking to Bob & Eve will secretly listen their talks
2.Network Spoofing -> Eve will say to Alice that I'm Bob , and retrieve all secrets from Alice
3.DOS Attack -> I want to destroy any website , I will give large number of fake clients to website that it will shut down.
HOW CAN WE SAVE OUR NETWORK?
1.Encrypt
2.Authenticate
3.Verify