So you want tthe client to access Domain A by clicking on a link.

That link should give the client a new URL redirecting him to Domain B.

Additionally Domain B should get some information generated on Domain A, but the client should be unable to see that information?

Question: Is it important that the client can't see the content of that information or is it important that he can't see that information is passed at all?

I think the only way to achieve this is by a connection between Domain A and B:

1. Client access A
2. A generates Information and a unique key and sends this to B
3. B stores this information
4. A redirects the cient to a URL on B. The URL contains this unique key
5. B recognises the unique key and retrieves the stored information

I think this is the way most adservers work.

But: Is this a perl question?