Download manager
Encyclopedia
A download manager is a computer program
dedicated to the task of downloading
(and sometimes uploading
) possibly unrelated stand-alone files from (and sometimes to) the Internet
for storage. This is unlike a World Wide Web
browser
, which is mainly intended to browse web page
s, composed of a multitude of smaller files, where error-free moving of files for permanent storage is of secondary importance. (A failed or incomplete web page file rarely ruins the page.) The typical download manager at a minimum provides means to recover from errors without losing the work already completed, and can optionally split the file to be downloaded (or uploaded) into 2 or more segments, which are then moved in parallel, potentially making the process faster within the limits of the available bandwidth. (A few servers are known to block moving files in parallel segments, on the principle that server capacity should be shared equally by all users.) Multi-source
is the name given to files that are downloaded in parallel.
Download managers are useful for very active Internet users. For dial-up
users, they can automatically dial the Internet Service Provider
at night, when rates or tariffs are usually much lower, download the specified files, and hang-up. They can record which links the user clicks on during the day, and queue these files for later download. For broadband users, download managers can help download very large files by resuming broken downloads, by limiting the bandwidth
used, so that other internet activities are not affected (slowed) and the server is not overloaded, or by automatically navigating a site and downloading pre-specified content (photo galleries, MP3 collections, etc.) this can also include automatically downloading whole sites and regularly updating them (see Mirroring
).
Many download managers support Metalink
, an XML file listing mirrors, checksums, and other information useful for downloading.
, were among the first adware
applications displaying a banner
ad in the user interface.
Adobe Download Manager is now exhibiting this same feature, while installing such software as Adobe Acrobat
.
applications (eMule
, BitTorrent, Gnutella
) and stream recorder
s (such as StreamBox VCR).
While download managers are designed to give users greater control over downloads, some downloaders are created to give that control to content distributors instead. Some software companies, for example Adobe http://www.adobe.com/products/acrobat/acrrmanager.html, provide such downloaders for downloading software on their own site. Presumably this increases reliability and reduces their technical support costs. A possible reason is increasing the control over redistribution of their software (even when the software is freeware
).
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
dedicated to the task of downloading
Uploading and downloading
In computer networks, to download means to receive data to a local system from a remote system, or to initiate such a data transfer. Examples of a remote system from which a download might be performed include a webserver, FTP server, email server, or other similar systems...
(and sometimes uploading
Uploading and downloading
In computer networks, to download means to receive data to a local system from a remote system, or to initiate such a data transfer. Examples of a remote system from which a download might be performed include a webserver, FTP server, email server, or other similar systems...
) possibly unrelated stand-alone files from (and sometimes to) the Internet
Internet
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...
for storage. This is unlike a World Wide Web
World Wide Web
The World Wide Web is a system of interlinked hypertext documents accessed via the Internet...
browser
Web browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
, which is mainly intended to browse web page
Web page
A web page or webpage is a document or information resource that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format, and may provide navigation to other web pages via hypertext...
s, composed of a multitude of smaller files, where error-free moving of files for permanent storage is of secondary importance. (A failed or incomplete web page file rarely ruins the page.) The typical download manager at a minimum provides means to recover from errors without losing the work already completed, and can optionally split the file to be downloaded (or uploaded) into 2 or more segments, which are then moved in parallel, potentially making the process faster within the limits of the available bandwidth. (A few servers are known to block moving files in parallel segments, on the principle that server capacity should be shared equally by all users.) Multi-source
Multi-source
Multi-source, as it applies to downloading data, or files from the internet, is a method of decreasing download time for large files by getting data from two or more sources.- Overview :...
is the name given to files that are downloaded in parallel.
Features
Download managers commonly include one or more of the following features:- Pausing the downloading of large files.
- Resuming broken or paused downloads (especially for very large files).
- Downloading files on poor connections.
- Downloading several files from a site automatically according to simple rules (file types, updated files, etc. - see also Offline Browser).
- Automatic recursive downloads (mirroring).
- Scheduled downloads (including, automatic hang-up and shutdown).
- Searching for mirror sites, and the handling of different connections to download the same file more quickly (segmented downloadingSegmented downloadingSegmented downloading can be a more efficient way of downloading files from many peers at once. The one single file is downloaded, in parallel, from several distinct sources or uploaders of the file...
). - Variable bandwidth usage.
- Automatic subfolder generation.
Download managers are useful for very active Internet users. For dial-up
Dial-up access
Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network to establish a dialled connection to an Internet service provider via telephone lines...
users, they can automatically dial the Internet Service Provider
Internet service provider
An Internet service provider is a company that provides access to the Internet. Access ISPs directly connect customers to the Internet using copper wires, wireless or fiber-optic connections. Hosting ISPs lease server space for smaller businesses and host other people servers...
at night, when rates or tariffs are usually much lower, download the specified files, and hang-up. They can record which links the user clicks on during the day, and queue these files for later download. For broadband users, download managers can help download very large files by resuming broken downloads, by limiting the bandwidth
Bandwidth (computing)
In computer networking and computer science, bandwidth, network bandwidth, data bandwidth, or digital bandwidth is a measure of available or consumed data communication resources expressed in bits/second or multiples of it .Note that in textbooks on wireless communications, modem data transmission,...
used, so that other internet activities are not affected (slowed) and the server is not overloaded, or by automatically navigating a site and downloading pre-specified content (photo galleries, MP3 collections, etc.) this can also include automatically downloading whole sites and regularly updating them (see Mirroring
Mirror (computing)
In computing, a mirror is an exact copy of a data set. On the Internet, a mirror site is an exact copy of another Internet site.Mirror sites are most commonly used to provide multiple sources of the same information, and are of particular value as a way of providing reliable access to large downloads...
).
Many download managers support Metalink
Metalink
Metalink is a cross-platform and cross-application Internet standard/framework/file format for programs that download, including download managers, BitTorrent clients, Web browsers, FTP clients, and P2P programs...
, an XML file listing mirrors, checksums, and other information useful for downloading.
Adware
Download managers, such as Go!ZillaGo!Zilla
Go!Zilla is a proprietary download manager originally developed by Aaron Ostler in 1995, and later purchased by Radiate in 1999, for use on Windows. It is shareware and its previous ad supported version drew controversy among users and privacy advocates...
, were among the first adware
Adware
Adware, or advertising-supported software, is any software package which automatically plays, displays, or downloads advertisements to a computer. These advertisements can be in the form of a pop-up. They may also be in the user interface of the software or on a screen presented to the user during...
applications displaying a banner
Banner
A banner is a flag or other piece of cloth bearing a symbol, logo, slogan or other message. Banner-making is an ancient craft.The word derives from late Latin bandum, a cloth out of which a flag is made...
ad in the user interface.
Adobe Download Manager is now exhibiting this same feature, while installing such software as Adobe Acrobat
Adobe Acrobat
Adobe Acrobat is a family of application software developed by Adobe Systems to view, create, manipulate, print and manage files in Portable Document Format . All members of the family, except Adobe Reader , are commercial software, while the latter is available as freeware and can be downloaded...
.
Related applications
Related to download managers are two other breeds of Internet programs, file-sharing peer-to-peerPeer-to-peer
Peer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads among peers. Peers are equally privileged, equipotent participants in the application...
applications (eMule
EMule
eMule is a free peer-to-peer file sharing application for Microsoft Windows. Started in May 2002 as an alternative to eDonkey2000, eMule now connects to both the eDonkey network and the Kad network...
, BitTorrent, Gnutella
Gnutella
Gnutella is a large peer-to-peer network which, at the time of its creation, was the first decentralized peer-to-peer network of its kind, leading to other, later networks adopting the model...
) and stream recorder
Stream recorder
Stream recorder, also called a stream ripper, is a computer program capable of saving a data stream – particularly streaming media such as encoded music or video – to a file, instead of playing it right away...
s (such as StreamBox VCR).
While download managers are designed to give users greater control over downloads, some downloaders are created to give that control to content distributors instead. Some software companies, for example Adobe http://www.adobe.com/products/acrobat/acrrmanager.html, provide such downloaders for downloading software on their own site. Presumably this increases reliability and reduces their technical support costs. A possible reason is increasing the control over redistribution of their software (even when the software is freeware
Freeware
Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...
).
External links
- Download Managers - reviews about Download Managers.