Chapter 11: Advanced Networking

Overview

Most of the time, people will install Ubuntu, configure the network during the installation, and not need to change it again. However, there are some situations where you will want to configure the network. This can happen if you have a laptop and frequently move between different networks, if you add in a second network card, or if you need more security than the default settings.

In many cases, changing the network configuration can be as simple as using a GUI. In other cases, you'll need to edit some configuration files in order to properly configure some adapters.

As mentioned in Chapter 10, the default Ubuntu installation is pretty secure because no network services are enabled. However, all your network traffic is probably still being sent unencrypted across the network. There are a couple of different ways you can enable encryption, authentication, and anonymity when accessing the network.

If you start turning on network services (see Chapter 12), you will need to make sure that your network is hardened. Tools like iptables can definitely help lock down a system.

Finally, when everything goes wrong, you will need to know how to debug the network. This is where tools like tcpdump, snort, and ethereal(a.k.a. Wireshark) come in handy.