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Be Your Own Telephone Company... with Asterisk

Strom CarlsonBlack Ratchet

Strom Carlson and Black Ratchet details strom Carlson & Black Ratchet, Be Your Own Telephone Company.

Summary

Architecture and Background

Strom Carlson & Black Ratchet, Be Your Own Telephone Company... With Asterisk Since the invention of the step-by-step switching office by Almon B. Strowger in 1889, telephone switching technology has constantly become more efficient, more complex and easier to manage.

Vulnerability Analysis

Today, anyone with a computer, a telephone and some spare time can assemble a homebrew telephone switching system and become their own miniature telephone company with the aid of a program called Asterisk. This presentation will give a brief overview of Asterisk, how to set it up, what it can do, and how to integrate it with your existing network. Furthermore, you will be introduced to a whole world of features and capabilities you didn't even know existed but which you will find yourself inexplicably compelled to set up and play with.

Exploitation and Demonstrations

Covered topics will include hardware, trunking, PSTN termination, integration with the Web and customization. A Q? a call-in Q?

Remediation and Defensive Strategies

Strom Carlson is the organizer of DC213 and has been playing with telephones for years now; he has an intense interest in the structure and history of the telephone network and will start yammering away for hours about it if you're not careful. He collects all things related to telephony (including recordings), and although he is rapidly running out of space in which to store his many cubic meters of telephone equipment, he will eagerly and compulsively snap up anything made or published by Western Electric if given the chance. He encourages all phone phreaks and interested parties to play extensively with the phone network and learn everything they can; he also encourages you to listen to everything on and to poke around Black Ratchet is just another phone phreak from Boston. He enjoys computers, radios, and, of course, anything remotely related to the Public Switched Telephone network. He has been playing with telephones since he was eleven, and after a somewhat lengthy sabbatical in college, had a relapse and returned to his old ways in late 2003. He is the organizer and webmaster of Yet Another Payphone List at and is an active member of the Digital Dawg Pound at He can be found at and on

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