The Invisible Playground: Phone Phreaking and the Criminalization of Curiosity
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Exploding the Phone : The Untold Story of the Teenagers and Outlaws Who Hacked Ma Bell
author: Phil Lapsley
publisher: Grove Press
pub date: 02.05.2013
pp: 416
tags: Science & Technology , History

Jason Brown on Exploding the Phone : The Untold Story of the Teenagers and Outlaws Who Hacked Ma Bell

The Invisible Playground: Phone Phreaking and the Criminalization of Curiosity

April 11th, 2013 reset - +

ON SOME NIGHTS in the early 1980s, the pauses between certain busy signals in Southern California were filled with a gibbering chaos of voices nearly as loud as the beeps themselves. On other nights, there might be a lone male voice solemnly chanting “Hello” into the pause, lunging with pubescent urgency at any female voice responding with a confused “Hello?” A glitch in the pre-digital phone circuits turned some busy signals into party lines, at least for as long as you could stand the constant beeping. If you wanted to have an actual conversation with one of these intermittent voices, you still wouldn’t want to holler out your home number to the random weirdos hanging out on busy signal circuits. So you might give out the number of a “loop around” — another quirk in the system which allowed two people to connect directly, but still anonymously and toll free.

By the time I heard the howling voices between the beeps in the early 1980s, the network hidden inside the phone switches was degraded and debauched, composed of vestigial chat lines that would soon go silent. But just a decade or two earlier, “talkable” busy signals and loop arounds were more than a free way for bored kids to hang out and trade numbers. As Phil Lapsley points out in his new book Exploding the Phone: The Untold Story of the Teenagers and Outlaws Who Hacked Ma Bell, the voices between the beeps also served as a subtle introduction, a way into a hidden world.

Lapsley’s book is the definitive history of the Golden Age of “phone phreaking” in the 1960s and 70s, when these quirks in the system were the basic tools used by dedicated network explorers to keep in touch and share knowledge. It documents a strange time when the most complex single machine on the planet could be controlled with bird whistles.

It started with a simple engineering decision in a more innocent time. The machines that replaced human switchboard operators in the forties and fifties listened for control signals over the same lines that people talked over. In particular, they listened for a high-pitched tone (seventh octave E, or 2600 hertz) to signal that a phone line was on the hook and should not be billed. Once in a while, someone might accidentally make this tone, resulting in a confused switch and a dropped call. But as long as no one was systematically making high-pitched tones into their phone — and who would ever do something like that? — the whole thing worked fine.

Around 1957, a seven-year-old blind kid with perfect pitch started systematically whistling high-pitched tones into his phone. After a few years of experimentation, Joe Engressia was able to whistle free phone calls. Other people figured out how to do the same thing using bird calls and toy flutes — bosun’s whistle given away in Cap’n Crunch cereal boxes made a perfect 2600 hertz tone. They invented electronic devices to mimic the control tones: “blue boxes” to hide you from the phone company’s billing system and “red boxes” to trick pay phones by mimicking the sound of a coin falling into a slot.

The kids found hidden conference lines to share tips. One of the most influential was the 2111 conference, born in May 1970 when a teletype circuit deep inside a Vancouver phone switch was misconfigured so that any number of people could connect to each other for free, provided they knew the trick. A core group of phone hackers gathered on the 2111 conference, including Engressia (who, at 22-years-old, was called the Old Man), and one particularly intense guy named John Draper, who chose a handle based on that infamous cereal box whistle: “Captain Crunch.”

Back when there was only one phone company (AT&T) and a five-minute long-distance call could cost the equivalent of $25, the incentives for hacking the system were clear. Mafia bookies, whose business relied on constant long distance calls, quickly realized that phone phreaking hardware was a fantastic way to increase their profits. Others saw it as a political act. The Yippies published phone phreaking guides, declaring free calls a protest against a phone company monopoly that supported the Vietnam War with its taxes. But most phone phreaks were in it for the pure joy of exploration — what Apple co-founder Steve Wozniak describes in his foreword to Exploding the Phone as the magical adventure of finding a crack in the system, a way to get in and discover something.

AT&T could patch some of the minor glitches, but they couldn’t fix the basic vulnerability that the control system was hearing the sounds people made into their phones as possible commands. It was deeply embedded into the phone system itself, hardwired into the massive network of electromechanical switches that had taken them decades to design and build. So the only way they could stop people from controlling their network with toys and mouth noises was to gut it and replace it with new switching systems that hadn’t even been invented yet. They would be stuck with blue boxes and phone phreaks for at least another decade, and the best they could do was try and keep the situation as quiet as possible.

But the open secret of the phone system’s vulnerability became public knowledge with an article in the October 1971 issue of Esquire by Ron Rosenbaum entitled “Secrets of the Little Blue Box.” Rosenbaum laid out the whole situation: how it would take the phone company years to upgrade the phone system, the relative ease of manipulating it in the meantime, and the existence of an underground network sharing tricks and tools. His description of phone phreaking was influenced by Thomas Pynchon’s The Crying of Lot 49, and he gave the nerdy practice a hip cultural identity. While the core group called themselves phone freaks, it was Rosenbaum who came up with the clever branding of “phreak” with a ph. And while the phone tricks were fascinating, it was the way he described the phreaks themselves that captured people’s imagination: granddaddy phone phreak Engressia whistling out calls to other blind phone phreaks around the world; a guy identified as “Al Gilbertson” describing his thousand-unit blue box orders from the mob; the legendary Captain Crunch bragging about his tandem stacking prowess and his illicit calls to Russia. These were the weirdos who hung out on busy signal circuits, the kind of people who explored the world hidden inside of what most people saw as a banal appliance.

Lapsley describes Rosenbaum’s story as “a telephonic cross between an acid trip and Gulliver’s Travels. It seemed like it had to be fiction.” But, for some readers, the reality of these characters, with their secret identities and underground world, was a mystery worth investigating. Steve Wozniak’s parents happened to have a subscription to Esquire, and as soon as he finished Rosenbaum’s story, Wozniak, who was about to start classes at Berkeley, called up high school senior Steve Jobs and read it to him over the phone. They immediately set out to solve the puzzle, dreaming of meeting people like Captain Crunch. All the way home from the Stanford library where they had found the frequencies for controlling the phone system, they kept repeating, “Holy shit, it's real.” Wozniak designed a blue box, and they became phone phreaks. Woz choose the phreaker handle “Berkeley Blue.” Jobs was “Oaf Tobar.” They did meet Captain Crunch, who visited Wozniak’s Berkeley dorm room, and on the way back to Silicon Valley from that meeting, the electrical system in Steve Jobs’ car died. They tried to use their blue box to make a free call to the infamous Captain from a gas station pay phone (a dubious rescuer). When the cops showed up, Woz didn’t even have time to drop the box.

The crowd pleasers in Exploding the Phone are anecdotes like this, in which two future billionaires are grilled about their illegal phreaker gear in the back of a police car, with their lives and a significant chunk of America’s future GDP hanging in the balance. But the deeper wonder of this book is the way Lapsley goes beyond these often-repeated highlight reels of nerd lore, charting the intricate webs of interconnection around the phone hacking community, by following the overlapping lives of phreaks, engineers, bookies, FBI agents, and corporate security officers. They would trade roles over the years, with phreaky phone company techs leaking info to hackers, phreaks getting phone company security jobs, underground hackers founding major corporations. Joe Engressia moved into a high-rise apartment in Denver, adopted the handle “Highrise Joe” (he would later legally change his name to “Joybubbles”), and got a job with Mountain Bell as a network troubleshooter.


The layers of hacker nostalgia excavated by Exploding the Phone are geologically dense, but Lapsley, to his credit, cuts through some of the romanticism by supplying us with substantial accounts of the corporate and government side of the phreaking story. Lapsley dug through AT&T’s archives, declassified hundreds of FBI records, and interviewed technicians and security officers. And he did it just in time. The early phone phreaks were teenagers in the 1960s, but the phone company workers were usually much older, and many of them are already gone. Without these insider accounts, much of the history of phone hacking could have remained secret, or simply lost, forever.

With this fuller history, Lapsley lays out the foundations of the systems we live in now. Not the specific tools we use, which are rotating into obsolescence in an accelerating blur, but the systems our tools are embedded within, and our notions of security, freedom, criminality, privacy. During the years that AT&T was struggling to invent a new phone technology, they also forged new legal justifications for surveilling users and prosecuting hackers. By definition, they had no idea who was hiding from their billing system, so they set up a blanket surveillance program which tapped around 33 million phone calls between 1964 and 1970, recording more than a million and a half of them for further analysis. AT&T kept this program — code named Greenstar — a closely guarded secret, because they were pretty sure it was illegal, and they certainly didn’t want a court to confirm their suspicions. But this massive wiretapping program gave them a good idea who was defrauding their system, and it pointed them towards evidence that they could use in court. (In 1968, AT&T helped advise Congress on new legislation that made the Greenstar wiretapping retroactively legal. So that was one problem taken care of.)

The other problem AT&T faced was that, once they did identify someone using a blue box, they didn’t have a clear law to prosecute them with. So, guided by their blanket wiretapping program, they built cases against the most unsympathetic targets they could find: mafia bookies. In 1966, the FBI raided blue boxing bookies like Kenneth Hanna in Miami, Al Bubis in Los Angeles, Gill “The Brain” Beckley, and Frank “Lefty” Rosenthal (the guy portrayed by Robert DeNiro in Casino). But convicting mobsters wasn’t that easy, especially since federal prosecutors resisted AT&T’s implicit suggestion that the government should serve as bill collectors for their broken phone network.

In 1969, Kenneth Hanna’s appeal was denied by the Supreme Court, and the phone company finally had clear legal ground to prosecute anyone who evaded their billing system under the charge of “fraud by wire.” Before he could go to prison, Hanna was found shot and stuffed in the trunk of a car in the Atlanta airport parking lot. Presumably the mob didn't want to risk him becoming an informant. But, for the authorities, he'd already served his purpose. Phone phreaking had become an unambiguous federal felony, and as Lapsley points out, a new crime had been invented: criminal curiosity. 

On April 2, 1976, John Draper was arrested by the FBI for fraud by wire. Still on probation from his first conviction, he was caught with a red box in his pocket and the operating manual for the federal criminal database in his apartment. He agreed to a plea deal, and on August 23, 1976, Captain Crunch went in to the federal pen at Lompoc for four months — the first phone phreak to get jail time purely for hacking. That same year, AT&T started upgrading their switches to digital, and over the next decade, the magic boxes and bird song spells stopped working. Many of the phreaks started playing with “beige boxes” — computers connected to modems. There would always be a network to explore, somewhere. But the Golden Age of phone phreaking had come to an end.


Because it was built on the shifting ground of someone else’s network architecture, the culture of phone phreaking always had a certain built-in nostalgia. Even in Rosenbaum’s 1971 article, one of the phreaks (identified only as “Ralph”) eloquently mourned the passing of the 2111 conference circuit, which had been around for less than a year:

You could feel something going on in the lines. Some static began showing up, then some whistling wheezing sound. Then there were breaks. Some people got cut off and called right back in, but after a while some people were finding they were cut off and couldn't get back in at all. It was terrible. I lost it about one a.m., but managed to slip in again and stay on until the thing died...

As a history of obsolescence, Exploding the Phone is unsurprisingly elegiac about the close of the Golden Era of phreaking; its final chapters are titled “Snitch,” “Crunched,” “Twilight,” and “Nightfall.” In an epilogue, Lapsley describes the outpouring of memorials when the last circuit in the continental United States that could be blue boxed (Waiwina, Minnesota, population: 70) was finally disconnected on June 15, 2006. Phreaks from across the county called in to a special voicemail line to pay their respects to a system that had been out of widespread use for 40 years.

The inside covers of Exploding the Phone display a map of the old long distance lines, captioned “The Playground”; when the old system was phased out and phreaking criminalized, that playground went dark. But while the analog systems exploited by the phone phreaks are now nothing more than steampunk fairy tales, the social and legal systems that AT&T put in place during the Golden Age of phreaking have not merely remained in place — they have grown and thrived. And in the decades since prosecutors first used the mafia as scapegoats, the ratchet has only gone in one direction, tightening restrictions around criminalized curiosity while expanding the range of freedom for owners and enforcers.


"The Playground"
Image courtesy of Grove /Atlantic, from
Exploding the Phone

Phone phreaks talked about getting busted by the phone company in a way that would sound silly if we were talking about AT&T or Google today. And it is indeed strange to think of Ma Bell’s quasi-governmental security force: hard-boiled guys in trench coats staking out phone booths, waiting for a hippie to toot a toy or beep a box. But part of the reason this seems strange is because corporations don’t really need the guys in trench coats anymore. The mechanisms of state and corporate surveillance are now completely embedded in our daily lives.

In 2010, Andrew Auernheimer — better known as “Weev” — found a security flaw in AT&T’s network that publicly exposed the personal information of iPad owners. He says he notified AT&T about the flaw and gave them a chance to patch it before he finally handed everything over to Gawker, and emailed the US Attorney’s office in New Jersey, notifying them of AT&T’s public exposure of customer data. Since the founders of Apple got their start in consumer electronics by selling tools to exploit AT&T’s insecure network (Jobs and Wozniak sold blue boxes for $170 a pop, not far from the inflation-adjusted price of an iPad today), today’s security researchers might have reasonably expected merciful treatment when they help the same company by notifying them of their failure to protect the personal information of iPad owners. But on March 18, 2013, Auernheimer was sentenced to three and a half years in jail. Which wasn’t even the harshest sentence he could have been given: Auernheimer was facing up to 10 years for the crime of letting the world know about AT&T’s broken security. When he committed suicide earlier this year, Aaron Swartz was facing a possible 35 years for the crime of downloading freely available articles. Not only is the old Playground closed: any form of network exploration is strictly forbidden.

While the original analog phreaker playground may be long gone, its digital descendants have evolved into playgrounds for insiders, whose activities we only hear about in whispers and leaks. In 2006, former AT&T technician Mark Klein exposed the National Security Agency’s illegal wiretapping program, which housed equipment in AT&T’s own buildings.  In 2008, 50 years after retroactively legalizing the Greenstar wiretapping, Congress retroactively immunized telecom carriers for their national security wiretapping. In 2011, former NSA code breaker William Binney revealed that the NSA was working with AT&T and other telecom companies to store phone records for “everyone in the country.” (In the vaguely New Age-y sci-fi spirit of Greenstar, they even code named the program “Stellar Wind.”) The NSA is building a $4 billion data center to store this unprecedented trove of data, sifting it for interesting patterns, finding novel, unexpected things to do with it.

The mutant progeny of the old phreaker playground will be a tightly-guarded bunker in the Utah desert where all of our old conversations will lie tangled together like a nest of hibernating snakes, connecting us in secret ways we may never fully understand, explored in ways we will probably never know.


At Phil Lapsley’s Skylight Books reading a couple of months ago, I suspected the leather-jacketed guy in the second row was an old school phone phreak. The way he gave a knowing eye to everyone who sat down near him, coiled to pounce on any question. Clearly he had some personal experiences he needed to share. From the start of Lapsley’s talk, he interjected tandem stacking anecdotes and technical specifications, and it was soon clear that this was not just any phreak. It was Captain Crunch.

Lapsley handled the Captain’s continual interruptions with well-practiced toleration, as you might expect of someone who had spent the better part of a decade writing a book which features him as a central figure. (In the Sources and Notes section of Exploding the Phone, Lapsley described how his early research into phone phreaks involved giving the Captain a piggyback ride around his Burbank apartment — a form of “energy work” which Draper apparently requires of everyone who wants to interview him.)

After Lapsley’s reading, I asked Draper to sign his picture in Exploding the Phone, and he obliged with a shaky “Cap’n Crunch.” The photograph is from 1971, when the Captain was nearing the height of his fame as a phreak; in it, he poses with two other young dudes (Bob Gudgel and Jay Dee Pritchard) who had gone on a road trip to rural Washington State to explore their local phone system. They’re in the town of Duvall, posing on the sidewalk of a quiet main street at a pay phone, a kiosk from the 1960s, perched on a short barber-striped pole. From the looks on their faces, they know what they’re about to do to that innocent small-town phone is naughty. Perverse.

About a decade after this iconic photo was taken, I started spending summers in Duvall, a little farm town where the infrastructure didn't get updated much. I remember that barber-striped pay phone in front of some quaint old shop. Or I've mostly convinced myself that I remember. Maybe I even used that ordinary phone to make some ordinary call.

The phreaks were connoisseurs of switches, savoring the delicate differences of clicks and line noise, refining their palettes on the terroir of regional system configurations, the specific ka-chunk of a reconfigured circuit, the unique hum of a secret conference line, all navigated by physical sensation. It all seems like an arcane mythology now. But “land lines” can also seem that way to people who were born into a haze of wireless data. Talking to people through a strand of copper wire, paging them with the supplication of a mechanical bell — it already sounds like a quaint spiritualist ritual. Is it so much more irrational to imagine that poor old pay phone in Duvall harboring some vague imprint of how it had been misused?

The summer that Captain Crunch was sentenced to prison, I remember hearing on a car radio that the Liberty Bell would be rung for the bicentennial. We were driving on a highway somewhere in the middle of nowhere, maybe a desert in Utah or a suburb of North Texas. Excited to participate in the national celebration, I rolled down the window, closed my eyes, and strained to hear this special sound over the roaring highway wind.

I dont remember the adult driving the car trying to disabuse me of my idea that I could hear a bell from thousands of miles away. I probably looked really cute with my head hanging out the window, trying to catch an impossible sound, believing there was a special frequency that travels everywhere, a secret sound that you can hear with the right kind of ears. I still think I was right. We don't always hear it. But its always there, ringing.