Sunday, May 03, 2009

What is Metalink

(please note that: this is not for the Advance Versatile internet users)

Basically when your downloading files through the internet, there are several methods to do that.most of these methods are popular among the internet users

*Downloading via HTTP
*Downloading via FTP

But other two methods are not popular among the fresh users in internet.they are wasting their valuable time for find out how large files (such as movies or ISO files such as linux distribution files) get downloaded to their desktop without having corrupted.sometimes they are using legend HTTP and FTP that doesn't support download resuming and checksum verification.
Other two methods are

*Downloading via BitTorrent
*Downloading via Metalinks

why do we need download resuming and checksum verification?

Idea of download resuming is obvious I'm not going to explain it here but the concept of checksum verification is not know most of users. i will explain A to Z about chechsum verification in my future blogspot.

Brief explanation about BitTorrent (Tm)

BitTorrent is a protocol (a set of rules and description of how to do things) allowing you to download files quickly by allowing people downloading the file to upload (distribute) parts of it at the same time. BitTorrent is often used for distribution of very large files such as movies linux distributions ISO files, very popular files and files available for free, as it is a lot cheaper, faster and more efficient to distribute files using BitTorrent than a regular download.

When you use BitTorrent, you make, distribute and get files. To make and share a file or group of files through BitTorrent, you first make it into a “torrent"--a small file which contains information about the files and about the computer that coordinates the file distribution. Others (refered to as "peers") find and open your torrent and begin downloading the pieces. As the file downloads to peers' machines, those peers also share the pieces they get with even more people who are also trying to download the same file. This sharing makes the file easier to download as more parts become available from multiple sources. Since the file is broken up into small pieces, little bandwidth is used to do the overall transfer. Once the file is finished downloading, the client software continues to share the completed file (becoming a "seed") with others looking for it. This also means the file can still be downloaded long after the original poster has stopped seeding the file.

you can get the BitTorrent clients here
http://www.bittorrent.com
http://www.utorrent.com/ (uTorrent is a light weight version of BitTorrent client both are producing BitTorrent, Inc)
Azures -http://azureus.sourceforge.net/ (Java based Open source Rich Torrent client. you need to install latest Java Runtime Environment - http://www.java.com before install Azures)

Metalink ! what is it?
Metalink is an open standard that bundles the various ways (FTP/HTTP/BitTorrent) to get files into one format for easier downloads. This makes it good for downloading large Movies or ISO files; particularly for people who can't use P2P because of restrictions from their ISP(internet service provider) or University. It can deliver very fast download speeds since most clients support multiple connections, to multiple mirrors, automatically. In addition, it can do automatic error detection, and correction.

Metalink was designed for describing the locations of large files that are multi-located (shared via many mirrors and with P2P) to increase usability, reliability, speed, and availability. If a server goes down during a download, download programs can automatically switch to another mirror. Or segments can be downloaded from different places at the same time, automatically, which can make downloads much faster. Besides location, it also describes content. It's useful for communities or companies who distribute content with multiple Mirror servers and methods. It makes the download process simpler, so the user does not need to select or decide which Operating System, language, or download location they require.

Metalinks Clients

DownThemAll!, a Firefox extension, is probably the easiest way for most people to try out Metalinks.

aria2 (Use aria2 and you won't have checksum errors,packages for openSUSE here) is the recommended Unix command line client, while KGet 2.0 in KDE 4 and wxDownload Fast (All platforms, but no Mac OS binary) (packages for openSUSE here) have a GUI.

SpeedDownload is available for Mac OS,
Retriever (Java) on all platforms,
Free Download Manager (GPL),
Orbit Downloader
GetRight and Net Transport on Windows.