Client side implementation of the bit torrent client is rather straight forward in 99.9% of the situations. You are basically going to a website where you can download a bit torrent client, download and install it and that’s it. However, there are some issues that may come up when dealing with the client side implementation of a bit torrent client.

First and foremost is a firewall. In general, most people’s firewall is set-up to automatically create rules that will allow a bit torrent client to gain access to a port of its or your choosing. However, this is not always the case as some people have their firewalls set-up to make no exceptions. If this is the case, the best way, and of course the easiest, is to change your firewall settings before installing the bit torrent client. If not, chances are, you will have to manually make an exception.

The bit torrent clients need access to a port in your computer. This is not a visual port, but rather a computer generated one. In many instances, you may already be utilizing some of your available ports. For example, if you access the internet to get your bit torrent client, you are connecting to another computer’s port 80.

It is these ports that allow simultaneous connections to the world. If you are in a network, and you have a router in your home or office, most likely you will have to access your router’s configuration and add the bit torrent client to create an exception. What this does, is it actually forwards any incoming connections that are asking for a particular port, directly to your computer. Otherwise, the incoming connection will not be allowed. Sometimes your ISP may be using a router of some type and therefore you may not be able to get them to forward a port request. Do not feel bad if this is the case, you can still download, but it may not be as fast. The reason it may be slow, is instead of another computer connecting to you, their computer will send a request to someone you have already been connected to you, which in turn, that request will be forwarded to you. This is known as pushing UDP, all that it does, is tells your bit torrent client to connect with them instead of them connecting to you. This is sometimes called a handshake as well.

You may notice if you ever check your stats with your bit torrent client that you only made X number of incoming connections, but you had X² “Handshakes.” These are instances where you connected to another computer instead of that computer connecting to you. It all works out in the long run as long as you download the file you wanted.

Popularity: 11% [?]

The Similarity-Enhanced Transfer was developed to help speed up the transfer process between nodes in the file sharing network. The way it works, is it looks for chunks of data that are exact or an almost exact copy of what the client application is looking for. This technique is known as hand printing and it is basically looking for the data the file needs to be completed. By looking for and downloading similar chunks, you can actually improve the download time by 71%. The lower the SET filter is set, the more similar pieces it can find and therefore the number of connections that can be made. This is important as while you are downloading a file, you can suffer lags in between connection while the client application is looking for exact matches. By lowering the SET limit, you can then close these soft spots or lagging download points drastically which if figure out over the length of the entire download, you can increase the download time by up to 71%.

However, on popular data, the SET will most likely not help your download capabilities as these are limited by your ISP. However, when it comes to less popular files that have little seeds available, you can then increase this download time drastically whi will make it worth the effort.

The SET was developed by a joint effort between Professor David Andersen, Himabindu Pucha and Dr. Michael Kaminsky. After the development of this file sharing protocol, it would later be integrated into the bit torrent protocol. It is for this reason, that the bit torrent client applications are very expedient when it comes to downloading files. This also plays an important role in the development if the bit torrent protocol’s rarest first paradigm. In the rarest first technique, the client application will hunt down the rarest portions of the requested file first using the SET concept, therefore making the rarest portion, the least rarest and this will continue indefinitely until a medium is found in which all the pieces of data have the same availability. Or until you finish downloading the file!

There are many other concepts that have been envisioned into the development of the bit torrent protocol to help with its popularity and speed. Regardless of the underlying technology involved, the bit torrent protocol is now considered to be the most popular file sharing protocol in the world. Users can be found in any country that has a public internet access. Yes, there are still some in which the citizens do not have sufficient, or any internet access at all. Some of these reasons for the lacking can be as simple as cost, while others may be due to government constraints and control on its people. None the less, the bit torrent network is still considered to be the largest community on the web and in the world to date.

Popularity: 23% [?]

One of the most unique peer to peer file sharing networks, is one that breaks all the rules in file sharing protocols. The network is known as a friend to friend file sharing network in which two users will connect directly utilizing passwords and digital signatures to verify the connection before a file can be shared.

Although it is possible to request or send a file to another without actually knowing who you are transferring with, you can not however, make connections with any users out side of your network.

It was Dan Bricklin who first used the name back in 2000, in which a peer to peer file sharing client can connect to another client in the same network, but requires a crypto key which is usually transferred via a more personal means like face to face. Many peer to peer file sharing clients are capable of friend to friend file sharing. These programs include Turtle, WASTE, Galet, GNUnet as well as Freenet.

Once connections are made and assuming that ones friends have static IP addresses, one could use their firewall to block any connection attempts by anyone whose IP address is unknown. The use of link connection and the small file sharing network also get rid of the need for and end to end encryption as each node can fully control who can use their client to transfer or forward files and queries.

Although a instant messenger may sound like a friend to friend file sharing network, it is nit unfortunately. This is due to the simple fact that instant messaging utilizes a public server whereas a friend to friend is a direct tunnel connection between friends who act as their own nodes on the network.

Any type of communication which uses a publicly available server, or even a server which is not directly on a node cannot be considered a friend to friend network which also includes a private direct connection hub as communications go through the hub at first.

The most common term today for a friend to friend file sharing network has become known as a darknet. What this means, is that in order to join a friend to friend file sharing network, you have to be trusted by one of the members in the network. While you can always start your own, you can also join a larger friend to friend network.

Friend to friend networks are more or less built on trust of the other members, and therefore any user is less likely to receive viruses or maleware since one can usually know who the file originated from and therefore stop the availability before full infection of the friend to friend network occurs.

Popularity: 47% [?]

Although in general, the concept of web based file sharing can be directed towards the use of 1 click FTP or HTTP file downloading, however, only the FTP allows uploading since the HTTP version is strictly downloading.

Along came the P2P and bit torrent file sharing protocols. The P2P network was the first to arrive on the scene, but unfortunately it was still a centralized file sharing network. Napster was one of these networks in which a server handles the storing of a file for others to download.

Following the P2P’s centralized network was the decentralization by the bit torrent protocol. But this was not enough for many people as their internet connection may not be fast enough for the download of a file. In response, a PHP based web server application was developed to allow someone to turn a high bandwidth server into their bit torrent client and once the file was downloaded, they could simply access it via FTP.

When this web based bit torrent client application was released, it did not have a sufficient amount of extras, so many people would make their own hacks. These hacks included the changing of lines of code as well as adding lines of code to the base PHP script. Although this issue would become overwhelming as people would add more hacks, they would also have to maintain logs of changes so they could do future hacks as well.

In response to all these issues involved with literally hacking the lines of PHP code, another person sat down and rewrote the entire install program to utilize all off the more popular hacks to this web based bit torrent client application.

This does not mean in any way shape or form that the web based bit torrent client is an attempt to recentralize the file sharing networks, but rather aide in the faster transfer of files amongst its peers. A user who has a dial-up connection, can install this bit torrent client application on a free hosted web server that offers PHP and databases, and once the download is complete, they can access it via FTP, which on some connections may be a sufficient amount faster that their standard dial-up access.

One of the major downfalls though, is the fact that using a server to download torrents of a dubious nature can make you more visible. Of course the number one reason some may opt for this selection though is not for their personal speed capabilities, but for the throttling that their ISP may do to their bit torrent connections. However you decide to access the bit torrent network, just remember that some files may be under copyright and therefore one must take into account the possibility of getting caught with pirated intellectual data.

Popularity: 100% [?]

To talk about the history of the bit torrent protocol and P2P file sharing, you cannot just simply start off with the P2P protocol, but rather like many stories, you have to start at the beginning.

1972 marked the birth of the file sharing revolution. This first form of peer file sharing was aptly known as Sneakerner due to the lack of interne access at the time. Sneakernet was exactly as it sounds, one would place a file on a floppy and deliver it in person or via mail.

It would be 6 years latter at the birth of the internet era that the first BBS would become available in 1978. Although back then the sharing of actual files was harder than it is today, the concept was there. It would not be until 2 years later that the BBS would evolve into the Usenet thanks to the development by Jim Ellis and Tom Truscott at Duke University.

1985 however, marked an important year to the file sharing idea. It was this same year that the File Transfer Protocol or FTP would be developed allowing people to share files via a centralized server.

Three years later the Internet Relay Chat was developed and replaced the MultiUser Talk protocol allowing for faster communications with others, starting the need for faster communications, this eventually led to the development of what is known as the World Wide Web today as it was developed by Tim Berners-Lee in 1990.

The next big thing in the file sharing arena was not PC, but it was Mac. Hotline was the file sharing network as it was introduced at the MacWorld Expo in 1997 and became the number one file sharing vehicle for the various Mac users around the world.

1998 marked the birth of MP3.COM as well as the release of the world’s first MP3 player which led MP3 Newswire to become the first digital media sharing website. It was with the birth of the MP3 and the need to convert music tracks to MP3 that would lead to the birth of the digital copyright infringement.

A year latter, Napster was to take the central stage as a completely illegal website that allowed someone to make a MP3 file of their favorite song and share it with others, this led to not just lawsuits, but several teenagers now have criminal records due to their downloading habits.

It was not until 2000 when the first decentralized file sharing network was developed. This decentralized network was the Gnutella-network and led to the birth of a new idealism in file sharing around the world.

Two years later, the bit torrent protocol would be debut to the world, and eventually take a choke-hold on the file sharing technology around the world.

Popularity: 78% [?]