Looked into a network installation of fedora there. It seems you need to setup http & ftp servers on the host along with booting from a cd.
So what are the advantages of installing linux over the network?
You don't need to use a cd, the big benefit of using network installation instead of a normal, physical medium based, installation is that you can install multiple machines at once without the need to ever insert a physical medium.
With kickstart it is also possible to automate the installation of an Fedora installation, i.e. you can automatically install the packages you want, modify the firewall or run arbitrary scripts.
Most systems support netboot, i.e. the network card can boot directly from the network via PXE and will download the bootloader via tftp. The bootloader itself may load the kernel and initrd either via http/ftp or bootp. Afterwards the initramfs have to load the rest of the system, typically either via http/ftp or nfs.
The major advantage is that you need no optical media (or other means of install), also that the netinstall will install the latest packages available (if you installed in other ways, you'd need to run an update first).
Also you can have a mirror in your local network if you need to install it in many machines, thus saving you the bandwidth.