Advanced Networking Features

Motivation

The network capabilities of Linux are not limited to what you have seen so far. This chapter gives you a list of what else you could do, without much details.

List of more Advanced Networking Topics

VLANs

You can run more then one network on the same wire, but to properly separate them there is the possibility of VLANs (IEEE 802.1Q, or often called dot1q ) where networks are separated by a 12 bit VLAN number. So you can have about 4096 different virtual LANs on a cable. Most larger switches support this so you can have different networks on the same switch. On some cables (e.g. interconnects between switchs) you would sent your packets with the VLAN header (tag) included. So called tagged ports. On others, where you have only one station in one particular virtual LAN they are sent untagged. The station does not know about any other VLANs at all.

In order to give a Linux server the option to be directly connected in multiple virtual LANs you would connect them to a tagged port and configure virtual interfaces for each VLAN number that you need to see.