Is there a name for this method?

cold call from an SEO company

[JenniferL]

Ok, so I get a call from an SEO company with the usual "guaranteed top 10 rankings in 30 days" blah blah. So I'm curious as to what method they use. He said they put a code into our site which refers the search engines to THEIR dns servers and to quote "their dns servers make our page look perfect to the SE's."
So, is there a name for what they are doing (other than trying to trick the SE's which is not good)?

[arrowman]

It's called DNS cloaking.

[JenniferL]

Thanks!

[Mr Bo Jangles]

and is Google immune to this or susceptible? If the latter, how come? Is it difficult for them to counteract?

Cheers,