for instance
normal link
http://www.sierraimaging.com/
deep link (this is a file stored deep in the web site)
https://www.sierraimaging.com/demos/WS_FTP.LOG
pay per use sites or ones that earn a living by punters reading the
advertisements wanted a way to stop people going straight to the
payload, and thus was born the referrer block.
A referrer is the name of the site you came from, or referred you
to the current site.
So in the embedded image case the referrer is
http://www.dpreview.com
since thats where you are following the link from, where you
clicked it, the apache web/https server at ofoto looks at the
referrer and if its not ofoto.com it refuses the link.
Also there are programs called proxy servers that do the blocking
as well, in a similar way.
Its a wide topic and you can read about it in most "how to setup a
web site" type guides. Though be warned http servers are associated
setups are very terse indeed
Its an interesting policy because its basically how the web works
in the first place, however in a lot of cases its fair, take
dpreview.com, a lot of people try to circumvent the adverts but its
how phil makes some of the money for the site, its free to us, a
bit like television.
heres a related story about deep linking, where Universal wants to
stop people deep linking.
http://www.wired.com/news/politics/0,1283,20948,00.html
http://www.insiderreports.com/storypage.asp_Q_ChanID_E_WB_A_StoryID_E_20000593
unfortuantely i picked it up along the way , i do a lot of
programming on web stuff and servers etc so the knowledge comes
with it. Maybe someone else has a good book reference, the only one
i can think of is the apache administrators guide by o'reilly but
its an advanced title.
charlie
as i said in other parts of this thread ofoto blocks referrers and
deep links like this..
charlie..
Keep shootin'
Lonnie
at the end
