Caller ID Spoofing - Technology and Methods

Technology and Methods

Caller ID is spoofed through a variety of methods and different technology. The most popular ways of spoofing Caller ID are through the use of VoIP or PRI lines.

Another method of spoofing is that of emulating the Bell 202 FSK signal. This method, informally called orange boxing, uses software that generates the audio signal which is then coupled to the telephone line during the call. The object is to deceive the called party into thinking that there is an incoming call waiting call from the spoofed number, when in fact there is no new incoming call. This technique often also involves an accomplice who may provide a secondary voice to complete the illusion of a call-waiting call. Because the orange box cannot truly spoof incoming caller ID prior to answer and relies to a certain extent on the guile of the caller, it is considered as much a social engineering technique as a technical hack.

Other methods include switch access to the Signaling System 7 network and social engineering telephone company operators, who place calls for you from the desired phone number.

In the past, Caller ID spoofing required an advanced knowledge of telephony equipment that could be quite expensive. However, with open source software (such as Asterisk or FreeSWITCH, and almost any VoIP company), one can spoof calls with minimal costs and effort.