unusual phenomenon

[hmcheung]

Hi,

Sometimes I encountered this phenomenon when browsing through the net:

In sample1.htm there is a link <a href='http://www.xxx.com/xxx/abc.asp?id_1=123&id_2=456'> . If I click this link from the page, I can get the query result I want. But if I copy this link and paste it back to the browser's address bar and press enter, it will bring me back to the homepage. How can this happen?

Thanks!

[parksie]

It's all about referrals. When you click on the link, the browser adds another header, like:

HTTP-Referrer: http://www.xxx.com/xxx/sample1.htm

The ASP checks for this, so that it knows what page it came from. If it's not there, it redirects you to the homepage. It's basically a security mechanism to stop people from hijacking your scripts.

[hmcheung]

Thanks!
where can I find some more information about referral page?
I'm very intested in this security measure. :>

[hmcheung]

is it possible that this phenomenon is done by setting cookies?