Re: Count online users question

Cookies, or browsersession. I found the latter to be very easy to work with. -- Kim Steinhaug --------------------------------------------------------------- There are 10 types of people when it comes to binary numbers: those who understand them, and those who don't. --------------------------------------------------------------- "Al" <php.newsgroups@allysays.com> wrote in message news:20031127005705.2729.qmail@pb1.pair.com... > > I am trying to figure an accurate way to calculate how many users are > > viewing a site, at any particular time. This task is very simple except > for > > one part - How do you determine when a person has left the site...apache > > hasn't served anymore requests from a particular ip for xx minutes ?? > > Hi Mike, > > There is no surefire way to measure the exact time a user leaves your site. > The most accurate way I can think of would be to use a hidden frame on all > your pages that refreshes itself every X seconds. When a user has not > requested that special tracking page for more than X seconds, you can assume > they have 'left' the site. > > However this solution seems like overkill for most purposes: you'll be > wasitng server resources and slowing down your users' experience on your > site. > > In response to your proposed method, most advertising associations > (including the US-based Internet Advertising Bureau) and web analytics > companies (such as Red Sherrif, Nielsens and Hitwise) define the end of a > user session on a website when there is 30 minutes without a further request > for a page from the site. > > And while you may be tempted to track only IP numbers, remember that many > users are behind shared IP numbers (e.g. firewalls) which may skew your > stats. You would be better off using cookies on user's machines to identify > them and log their accesses to a DB. > > Hope that helps, > > Al