Push Technology

URL pushing. I understand that one person (the one pushing) finds out, the end user he is about to oush to, IP address. He then requests a page and tricks the request header information as the end users IP so that it loads on their browser and notthe person pushing it.

What makes this work, what program language makes this work. Whre does one start learning about how to impliment it themselves for their own company WITHOUT outsourcing it. Any and all help is greatly appreciated.

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