Phone phreaking is well known from dacades, but the introduction of data services had increased related threats. Especially with the increase of IP telephony.
Gateway & Gatekeeper could stand for an open door to internet hackers.
(I'm wondering if IP telephony will really populate most cie as CISCO thinks)

[QUOTE]Full article here: Newer phone networks often are linked to internal corporate data networks, making them enticing targets for hackers, said Lisa Pierce, a research fellow for the Giga Information Group, a subsidiary of Forrester Research.

Hackers compromising PBX systems that run voice data services can use them as entryways into computer systems. From there they can steal corporate information, eavesdrop on conversations and create havoc on the system because no one knows where the attacks are coming from, she said.

"[When] you have internal data and voice lines on the same network, it's basically a welcome sign for hackers," Pierce added. "The implications can get frightening pretty quickly."

Unsecured corporate phone systems can leave open other back doors to a company's network. Kevin Mitnick, who spent five years in jail for hacking into telephone companies and stealing secret code from software industry titans, broke into software maker Novell Corp.'s network in a similar way.
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