It depends on the site, and their requirements for data-accuracy, etc.
Most often there are two options - one is to assume that people will
look at the page for at least (say) 30s, so any unique IPs within a 30s
window are considered new viewers and are counted towards some kind of
If it's a session based website (dynamically generated, often using PHP
or Perl) then a (somewhat) more accurate count can be generated by
seeing how many concurrent sessions are active. Though this is prone to
users just leaving and the sessions timing out all by themselves too...
There are other ways, but all fall mostly into the latter category of
the 'lies, damn lies and statistics' trio :-)
Cian Cullinan wrote:
> On Wed, 01 Dec 2004 19:12:22 +0000, John Reilly <jr at inconspicuous.org> wrote:
>>>On Tue, 2004-11-30 at 14:13, Cian Cullinan wrote:
>>>>>2) How can I tell how many people are currently viewing a web page (or
>>>even site)? Presumably once the page has loaded for them and they're
>>>just scrolling through it, not interacting, then there is no httpd
>>>process associated with them?
>>>>> Ok so, makes sense, but how do people work out how many viewers are
> looking at their pages at a given time? Where are they getting their
> info when they say something like "we get up to 600 concurrent viewers
> at a given time"? Some sort of php voodoo?
Maintained by the ILUG website team. The aim of Linux.ie is to
support and help commercial and private users of Linux in Ireland. You can
display ILUG news in your own webpages, read backend
information to find out how. Networking services kindly provided by HEAnet, server kindly donated by
Dell. Linux is a trademark of Linus Torvalds,
used with permission. No penguins were harmed in the production or maintenance
of this highly praised website. Looking for the
Indian Linux Users' Group? Try here. If you've read all this and aren't a lawyer: you should be!