The attacker packets send to the targeted host using a protocol like TCP or UDP. These protocols allow data to travel across networks without requiring a connection between endpoints. A packet sent over the Internet travels to its destination. If the router receives too much traffic, it may drop some packets, causing routers to arrive out of order.

When this happens, the receiving computer interprets the packets as legitimate data, and it then processes the information and performs actions based on the instructions contained within the packet. In other words, the receiving computer executes the code inside the packet.

This process repeats itself thousands of times per second, resulting in a huge amount of traffic being sent to the targeted host. Because the packets contain no identifying information about the sender, the target host doesn’t know where the traffic originated. As a result, the host becomes overwhelmed with traffic and stops responding to legitimate requests.

More info: The Future of Managed IT Services and How They Will Continue To Evolve