What is currently the best way to set a 3rd party cookie?

I'm reading a lot on this topic for some time now.

The information on the web about this topic is quite confusing.

Use case: A User visits site hostA.com, which includes a "tracking pixe开发者_Python百科l" from site hostB.com . The user never visited hostB.com before. hostB.com sets a cookie with the response.

Which browsers will accept and save the cookie? (I read about safari does not, is this true, is this only true for iframes?)

How does default security configuration effect the challenge?

Is it enough to set a "correct" P3P header? (It seams to help with some Versions of the Internet Explorer)

Is there a common, accepted solution for the challenge?

Is the only why to use flash LSOs?

Thanks stephan

You can only set cookies for the domain that the page came from (your site). 3rd party cookies are up to the user to control through their browser settings. I never allow them in the Internet Group just for the example you gave of a "Tracking Pixel"