ISC Exam Questions

What type of telephone fraud manipulates the line voltage to receive a tool-free call?

Phreakers are hackers who specialize in telephone fraud. What type of telephone fraud manipulates
the line voltage to receive a tool-free call?

A.
Red Boxes

B.
Blue Boxes

C.
White Boxes

D.
Black Boxes

Explanation:
A Black Box is a device that is hooked up to your phone that fixes your phone so that when you get a
call, the caller doesn’t get charged for the call. This is good for calls up to 1/2 hour, after 1/2 hour
the Phone Co. gets suspicious, and then you can guess what happens. The Red box basically
simulates the sounds of coins being dropped into the coin slot of a payphone. The traditional Red
Box consisting of a pair of Wien-bridge oscillators with the timing controlled by 555 timer chips. The
Blue Box, The mother of all boxes, The first box in history, which started the whole phreaking scene.
Invented by John Draper (aka “Captain Crunch”) in the early 60s, who discovered that by sending a
tone of 2600Hz over the telephone lines of AT&T, it was possible to make free calls. The White Box
turns a normal touch tone keypad into a portable unit. This kind of box can be commonly found in a
phone shop.