When I was a novice in the field of this internet i always seek to know all about how to download.
I was interested in knowing the step follows in downloading. So I'm writing this blog for those type of novice describing about four ways of downloading used in current time of internet.
All of them are so famous that they does not need name but still for them I'm giving names as well:-
1.The very famous and traditional one client server model:-
This is the method through which most of the server used to enable downloading till last decades infect still too some of the servers use this method.
This method uses client server method for its service. A client server method includes simple interaction of client with the server.
A client used to request for a file to server and server access the request by uploading the same file and client used to download that. Using TCP(Transmission control protocol) the program file split into packets which are sent to client.
Points in favor:-
- This method is easy to access.
- No need to have higher proficiency in networking.
- Doesn't work well while network is busy.
- Doesn't respond well when there is relatively large demand of the same file from the same server.
2. Mirror servers:-
This technology is being used by most of the servers in the current time. One can say it is a New or advanced version of client server model.
In this method software publishers uses mirror servers distributed globally to provide downloading service.
A mirror is an exact copy of the website on other server located on different locations. This server also have the same files as on the original server.
When a client request a file a list of mirror server is presented(you may often see while downloading: click here is the downloading didn't started automatically. this is what we call mirror.) This method is used for overcoming the problem raised by croud over one server.
3. Peer to peer:-
This is another popular method of networking. In this method no there is nothing like a server or a client all the computers are connected with each other. In this method networking and speed is quite well.
In the first two methods you use a web browser(or a dedicated download client) to download software. Every one on a particular peer to peer network uses a program called peer to peer download client and all such clients communicate with each other. For instance,everyone using the eMule client at the same time can share files with one another.
When you request a certain MP3 song, game, ebook etc. that request goes out to all the clients on that peer to peer network. If someone has that file, his client will send it down to your client.The disadvantage here is that if the user who is sending you the file goes offline, your transfer will be interrupted. Also, there is no mechanism to check leeches, people who takes files from others, but do not share them.
4. Bit Torrent:-
This technology is also based on peer to peer technology.This technology favors the client using high speed service.
When you use The BitTorrent protocol to download files, your BitTorrent client first need s to read a .torrent° file on the computer. This file contains pointer information that leads your computer to the seeds(and the file you want to download). The client then can communicate with a computer called the tracker*. Each shared file is tracked by one or more such computers.
Once the tracker receives your request for the file,it forward it to other computers (seeds**) that have a copy of the file.It also ensures that part of the file, in various proportions,are downloaded from various seeds to your computer.When parts arrive they are assembled into a complete file.
*Tracker- The computer that coordinates and monitors the file distribution. It ensures that you receive multiple pieces of the same file fro various seeds.
**Seed- A Computer that has a complete copy of the BitTorrent file. you download parts of the file simultaneously from multiple seeds.
°.torrent- A file with the torrent extension is a pointer file.It contains metadata that points to the tracker and also the seed that have the file you want to download.
Leech:- Clients like you who are in the process of downloading. If the number of leeches are less downloading will b relatively fast.
swarm : A group of seed that have the full file or those that arealso in the process of downloading it.
In the current time all of theses four methods of downloading are Damn populer. So start downloading using any of the above described method and have fun.
All the Best.
source- chip magazine
