"Most bad behaviour comes from insecurity."
- Debra Winger

Networks are built to be used, not abused. However, there are instances where the networks are put to malicious use, either knowingly or unknowingly. Malicious use could be a sudden burst of traffic on the network causing congestion and degrading the experience for users, directing traffic towards a critical server to overwhelm the server resources and hence make it unavailable, taking control of network nodes/devices to manipulate routing or snoop data sending traffic to spread virus/worms or other malicious code, and so on. If the network is not secured properly, the network is not reliable and cannot be entrusted by users to transport data with confidence.

A secure network ...

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