Book Image

Designing and Implementing Linux Firewalls and QoS using netfilter, iproute2, NAT and l7-filter

By : Lucian Gheorghe
Book Image

Designing and Implementing Linux Firewalls and QoS using netfilter, iproute2, NAT and l7-filter

By: Lucian Gheorghe

Overview of this book

Firewalls are used to protect your network from the outside world. Using a Linux firewall, you can do a lot more than just filtering packets. This book shows you how to implement Linux firewalls and Quality of Service using practical examples from very small to very large networks. After giving us a background of network security, the book moves on to explain the basic technologies we will work with, namely netfilter, iproute2, NAT and l7-filter. These form the crux of building Linux firewalls and QOS. The later part of the book covers 5 real-world networks for which we design the security policies, build the firewall, setup the script, and verify our installation. Providing only necessary theoretical background, the book takes a practical approach, presenting case studies and plenty of illustrative examples.
Table of Contents (14 chapters)
Designing and Implementing Linux Firewalls and QoS using netfilter, iproute2, NAT, and L7-filter
Credits
About the Author
About the Reviewer
Preface
Index

Chapter 8. Large Networks Case Studies

There are different points of view in designing and deploying large networks using Linux routers or dedicated routers that can handle very high data rates.

While some prefer to pay a large amount of money for dedicated routers for which they have technical support and well-defined technical characteristics and limitations, others want to reduce the costs by building such networks using powerful computers running Linux, offering a much larger flexibility in deployment.

This is not an easy choice at all. The business point of view has ups and downs when considering the two options. The biggest advantage of using dedicated routers from the business point of view is that the value of the network rises considerably if the network is built to be sold. What I mean is that if you build a large network using Cisco routers, you have more chance of selling it to a bigger provider than if you've build the network with Linux routers.

Using dedicated routers you...