In this chapter we saw a large network with four core routers and five core links, and discussed:
How to build a configuration for a large network—how to create BGP connections
What kind of security threads we should expect
How to filter DDoS attacks with a good script that detects and filters them
How to secure business-critical services like VoIP and billing databases
How to differentiate services by marking packets with different values for those services
How to solve a problem when one of the core links doesn't keep the mark of the packets
How to perform traffic shaping for customers who buy one, two, or three services that we created
Where to place the limit scripts for the customers