Download Server
Where having a download server may not be the first reason for getting a home
server, it's worth thinking about adding this role alongside another role to
take advantage of unused bandwidth when everyone is asleep. Instead of leaving
the job up to another computer, utilising the server puts it to good use when it
may be idle and saves energy by leaving the other computer off.
Before we begin, this topic will discuss methods of downloading using torrents
and Usenet. These have a very bad press due to the large numbers of pirating and
illegal activity, this is true but worth discussing how beneficial these
technologies are for distributing legal content by people and organisations that
without would not be able to.
Torrents are the latest in peer to peer sharing that reduces cost for people to
release new content by distributing the file to a small portion of other users,
who all in turn distribute to new users creating a cascade of multiple copies
available to all. A perfect example being free Linux distributions where costs
can be significantly reduced sharing the bandwidth amongst many, rather than
having the brunt of providing it all. Where Usenet was not originally created
for file transfer, it now benefits from an advanced form of error correction
that saves wasted bandwidth, and publishers who simply cannot afford to host the
files can use a bit of the immense server capacity from big Usenet companies at
a significantly reduced cost yet make it available to many.
Hardware
As a download server would be considered to many as an extra add on, it's good
to note that there are no real extra requirements in terms of hardware that
needs to be added. If there are to be any stipulations it would be to have
enough free hard drive space to satisfy downloads, as low free space warnings
will go unnoticed while you're out or asleep and may result in a slow computer
on the next visit to the server, complete with other processes that may of
failed due to the lack of space. Speed of drive is not of concern either, as the
biggest speed bottleneck will inevitably be the Internet connection speed.
Software
Usenet: The process for downloading from Usenet is split into three parts, downloading, parity and extracting, this is explained in details on the methods section. There is software like the free SABnzbd that automates the process, so this is recommended as a quick start method.

For more control there are utilities that can handle each part of the process. For downloading I recommend Newsbin for its easy to understand setup and layout. Parity or error correction can be handled with QuickPar, its a small free program that never made it out of beta stage but is very stable and works great. Finally for extracting files 7-Zip is again a free from that can open and extract all file type commonly seen on Usenet.



Torrents:
Due to its popularity there are a whole host of different clients to choose
from, each touting little tweaks to cater to different users. If you are staring
out I would recommend a standard bit torrent client, it offers the best user
friendly experience end ease of use.
The most common clients available are currently uTorrent and BitTorrent.
UTorrent is designed to be a lightweight basic application purely for accessing
and downloading from the torrent network, therefore ideal for slower computers.
BitTorrent on the other hand is the full featured program that adds more
features if needed, however the free version has some of the features limited
and is supported by advertising, as well as nagging to upgrade to a premium
version.


HTTP:
While they are thin on the ground compared to its dialup hay day, there are
still lots to be found that include better features for scheduling and managing
download speeds, as well as FTP integration. I recommend Free Download Manager
Lite as it combines the necessary features such as bandwidth limiting and the
ability to resume downloads for free and without any extras that are only there
to take up unnecessary system resources. The full version currently has support
for Torrents and YouTube downloading but if those features do not appeal the
Lite version is perfect for basic downloading.
