III. The Technical Aspects That Allowed Phreaking To Work

VI. What's Left For The Phreaking Community

VII. Bibliography.I. Introduction - The '60s and '70s

It's hard for one not to be familiar with the state of our nation in the '60s and'70s. The period was arguably the high point of independent thought for the century. Average, everyday people began to question and disagree with aspects of society that had formerly been respected and revered. The new line of thinking greatly influenced the way society would advanced through that period.

The period in question was marked by a particularly hostile attitude towards those who were in positions of authority. The public was unhappy with the events surrounding the Vietnam War. For the first time, there was a large number of people who felt the need to speak up for what they believed in, even if it was against the government. The nation began to see the laying of foundations towards equal civil rights and disarmament, and the reb

Eventually, phreaking made it's way into other areas of society and culture. As home computing became more popular, and the modem was made available to people, phreaking text files were typed up. Afterwards, these text files were posted to a Bulletin Board System (BBS). A BBS was a computer that was attached to a modem, run by an Systems Operator (SysOp) who was most likely the owner of the computer. The SysOp would allow users to call up his computer to leave postings and swap files to and from the hard disk. Other users would then be able to share their texts as well. These text files specified the workings of the telephone system or schematics for various types of boxes, drawn out in ANSI text font type. In some ways, these BBSs paved the way for the dial up internet that most of us use today.

A more interesting person in the history of phreaking is "Joe the Whistler." Rumor had it that Joe was born blind. He became interested in the workings of the phone company, and found that he had a special talent. He was able to whistle a perfect 2600Hz sound. It is said that other phreakers would call him to set their tones generators to his whistle.

One of the earliest known phreakers was Stewart Nelson. Stewart was a student at the Massachusetts Institute of Technology (MIT). In 1964, Stewart was able to program the MIT computer to play the proper MF tones needed to make the free phone calls. He could then record them onto a tape recorder to play them over the phone line. Stewart wasn't involved in the phreaking scene for the free calls. He was just curious as to how the phone system worked.

y picking up the phone and dialing out, the customer caused the local office to complete a loop with the class 4 toll office. However, the lines between each class 4 office and other hierarchical offices dealt with Multi-Frequency (MF) signaling. On these trunk lines, there was a 2600Hz signal ever present, to signify the trunk was idle (not being used). If the class 4 toll office needed to route a call, it would cease sending 2600 across that line, to tell the other switch to wait for further instructions. Then the switch would send a combination of MF signals to signify the start of a number (Key Pulse, or KP), then the actual number in dial (consisting of unique MF signals to represent the digits 0-9), followed by the signal to signify the end of the number (ST). Now, assume for example that you are calling an 800 number. 1-800-555-1212, for example. You pick up the phone and dial. When you dial the first digit, 1, the local office switch realizes that you're going!

At this point in time, the Public Switched Telephone Network (PSTN) was a primarily (if not completely) analog network. It was designed to handle analog voice signals. Likewise, it used analog signaling to inform CO equipment of various line states. IT is important to mention that this signaling scheme was in-band. In-band means that the signals were sent over the normal telephone line, right along with the voice signals, and staying within the bandwidth of the line. Sometimes, while placing a call, one would actually be able to hear the office switches signaling each other, especially during a long distance phone call. This is due to the relationship between local offices (class 5 switching systems) and toll offices (class 4 switching systems), in respect to the trunk lines they share. These lines were loop start lines. This means that an off hook signal was given to the line if the loop (or circuit) was completed. If the loop was open, the line was not in use. Bu!

Eventually, the phone company became wise to the situation. Although the process of using in-band signaling was saving them a fortune on cables and equipment, they realized that they were losing too much face. The general public didn't like to see kids going to jail for a relat

Some common words found in the essay are:
Technological Advancements, Network PSTN, Plan NPA, Vietnam War, Phreaking Community, Operator SysOp, Pulse KP, Hacker Quarterly, Cap'n Crunch, Ma Bell, phone system, toll office, class 4, phreaking community, text files, phone company, '60s '70s, april 2001, 27 april 2001, 27 april, class 4 toll, office switch, 4 toll office, iii technical aspects, culture famous phreakers,
Approximate Word count = 2674
Approximate Pages = 11 (250 words per page double spaced)