IPs or User Agent

[joas]

I wrote an ASP page that checks the User Agent then displays the page accordingly. Should I also check the IP? Is it best to check both?

[msgraph]

Hi Joas,

It would be less of a load on your server to check the UA first then give the appropriate page instead of cross-checking from a list of IP's first.

Then you can set up something as a safeguard to verify if that user agent is actually coming from a search engine. Like if Slurp or Scooter is present then check IP. That way you won't have to verify the IP of every single user.

Although it is very easy for someone to spoof a user agent it is a much safer route to go this way. Some search engine spiders change their IP's. If you have your redirection judgement pulled off a list of IP's and they change their IP address for that spider, then they will get the page for the common user.

[Air]

Welcome to WmW joas.

The problem I see with using that method is you'll miss the spiders that come in using a different User Agent than the one you are expecting. Quite a few show up with Mozilla something or other, that means they will slip through and miss getting the optimized page(s).

[cirelle]

>> I wrote an ASP page that checks the User Agent then displays the page accordingly. Should I also check the IP? Is it best to check both?

I agree with Air, I use a beefy server running a sql database over 100Mbs to do my checks and there is little if any overhead to make several checks. If it looks funky I deliver the standard page.

As you are familiar with ASP you must be aware of the active x controls that can make you look like anything.

my 2c