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Agora (web browser)

For other uses, see Agora (disambiguation).

Agora
Original author(s)Arthur Secret[1]
Developer(s)World Wide Web Consortium / CERN
Final release
0.8f[2] / 2 July 1997; 27 years ago (1997-07-02)[3]
Written inPerl[4]
Operating systemDEC Alpha[4]
PlatformPerl[4]
Available inEnglish
Typeweb browser
LicenseW3C Software Notice and License/CERN open source copyright
Websitew3.org/Agora/ at the Wayback Machine (archived 2 August 1997)
www.w3.org/History/1996/WWW/Agora/

Agora was a World Wide Web email browser that served as a proof of concept to help people use the full internet.[5][6] Agora was an email-based web browser designed for non-graphic terminals and to help people without full access to the internet such as in developing countries or without a permanent internet connection.[7][8] Similar to W3Gate, Agora was a server application designed to fetch HTML documents through e-mail rather than http.[9]

Functionality

Agora, for those who cannot be in the Arena[3]

Agora was not a client application. To access the Internet you had to install the Agora browser on a server and send Agora an email with the requested URL.[5] The Agora application would send an email back with the requested content of the link. The email which was sent by the server, contained the HTML source code so that a normal web browser was able to display the page as it should be[10] or in a lynx-style.[11] Different options made browsing easier.[12] The servers could be configured differently so that some servers sent emails back containing only JavaScript, because the content was deeper on the page.[10] Agora was praised for handling frames correctly, although other similar applications were able to handle this by serving the source code and rerequest the used frame.[10]

Features

Although Agora was based on email communication it was able to search by different search engines: Archie, MetaCrawler, Lycos, Yahoo!, WAIS Search in Oxford Univ, Hyper RFC, WebCrawler, Veronica Search, AltaVista and Google.[13]

Agora limits the number of requests processed in each message to 10 to prevent the service from being attacked by messages containing excessive commands that could cause a DDOS attack.[9]

Supported protocols

The Agora server is based on the Line Mode Browser[14] and on the libwww and thus it supported different kinds of internet protocols besides the classical http and gopher browsing, namely NNTP,[15] Archie,[15] Finger,[15] WAIS.[13]

Although Agora was able to handle many protocols, the interactive telnet protocol was an exception.[2]

Version history

From Agora 0.7d it was possible to search some searchable sites by adding the search terms separated by spaces after the URL, but this would not work with forms.[2] Since Agora version 0.8e it was possible to split the requested URLs into two or more lines.[2] Data compression with uuencoded by gzip or zip was also integrated.[2] Agora version 0.8f determined frames and linked pictures goto and the answer mail get help in these cases.[2]

Limitations

One limitation of Agora was that it had an integrated limit for the output mail of about 10,000 lines (originally 5,000) primarily to protect users and the network from excessive bandwidth/resource usage.[2][9] With this limitation, uuencoded files would not exceed 1 megabyte because some operating systems and email clients had problems with files larger than 1MB.[2] Uuencoded files used too much bandwidth and so data compression was integrated.[2]

Since most websites contained links to inline images or binary files such as archives/executables Agora had to uuencode these files prior to sending them.[5][9]

Usenet support was read only because the server was anonymous.[13]

Further development

In version 0.9 users were able to fill in forms.[4] This version was never developed.[citation needed] The World Wide Web Consortium (W3C) servers were shut down because of the heavy load. Secret created the software to set up as a local strategy, but that did not work at that time. The consequences were that the W3C servers got too many requests and they had to shut down their Agora implementation.[16][17]

System requirements

To run Agora on a server, the server had to have Perl installed.[4] The libwww binaries www_*.*.Z had to be in the same directory.[4]

Criticism

Agora ignored completely the different kinds of applets which were popular at that time: Tcl, Tk, Java and Python.[2] Agora could not handle HTML tables properly.[2] The Usenet support was incomplete and created problems in translating the answer in formatted text; also, some newsgroups caused a crash.[13] It could not handle Chinese, Japanese, Korean web pages.[13]

References

  1. ^ Secret, Arthur (30 April 1996). "Arthur Secret". World Wide Web Consortium. Retrieved 23 June 2010.
  2. ^ a b c d e f g h i j k Sasse, Hugh. "Agora: Retrieving WWW Documents through mail". De Montfort University. Archived from the original on 17 January 2003. Retrieved 24 June 2010.
  3. ^ a b Secret, Arthur (2 July 1997). "Agora". World Wide Web Consortium. Retrieved 20 November 2013.
  4. ^ a b c d e f README file in the packed source code and in the packed executable of Agora 0.8.
  5. ^ a b c Secret, Arthur (12 November 1996). "Agora". World Wide Web Consortium. Archived from the original on 6 June 1997. Retrieved 20 June 2010.
  6. ^ Daniel Dardailler; Judy Brewer. "FINAL REPORT - DE 4105 - WAI". Web Accessibility Initiative. World Wide Web Consortium. Retrieved 23 June 2010.
  7. ^ Sosa-Iudicissa, Marcelo C.; Organization, Pan American Health; Association, International Medical Informatics (February 1997). Internet, telematics, and health. IOS Press. p. 145. ISBN 978-90-5199-289-2.
  8. ^ Tim Berners Lee (1 May 1995). "Getting Started with WWW". World Wide Web Consortium. Retrieved 25 June 2010.
  9. ^ a b c d Manfred Bogen; Guido Hansen; Michael Lenz. "W3Gate: Use and Abuse". German National Research Center for Information Technology. Archived from the original on 21 June 2010. Retrieved 29 June 2010.
  10. ^ a b c "G.E.Boyd's How To Do Just About Anything by email - Part 1". GeoCities. 11 August 2000. Archived from the original on 17 August 2000. Retrieved 24 June 2010.
  11. ^ WWWWolf (6 May 2001). "Agora". Everything2. Archived from the original on 17 June 2010. Retrieved 23 June 2010.
  12. ^ Secret, Arthur (23 June 1995). "Retrieval of documents through mail". World Wide Web Consortium. Archived from the original on 6 June 1997. Retrieved 20 June 2010.
  13. ^ a b c d e Secret, Arthur (13 August 1996). "Agora: Retrieving WWW Documents through mail". Archived from the original on 13 July 2010. Retrieved 25 June 2010.
  14. ^ Sendall, Mike (29 March 1995). "World Wide Web Clients". World Wide Web Consortium. Archived from the original on 23 August 2010. Retrieved 10 August 2010.
  15. ^ a b c "G.E.Boyd's How To Do Just About Anything by email - Part 2". GeoCities. 10 September 2000. Archived from the original on 10 March 2001. Retrieved 25 June 2010.
  16. ^ Moberg, Vic (16 November 1995). "WWW> Agora Web by Email Service Down for the Count". University of Wisconsin-Madison. Retrieved 26 June 2010.
  17. ^ "Landmark's E-Mail Echo". Landmark Computer Labs. 1 February 1996. Retrieved 26 June 2010.
Quelle: https://en.wikipedia.org/wiki/Agora_(web_browser)