Security in Computing (3rd Edition)

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Network Security War Stories CS 161/194-1 Anthony D. Joseph September 7, 2005 September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 2 About Me Joined faculty in 1998 – MIT SB, MS, PhD Contact info – adj @ cs.berkeley.edu – http://www.cs.berkeley.edu/~adj/ Research Areas: – Mobile/wireless computing, network security, and security testbeds Office hours: 675 Soda Hall, M/Tu 1-2pm September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 3 Outline War stories from the Telecom industry War stories from the Internet: Worms and Viruses Crackers: from prestige to profit Lessons to be learned September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 4 Phone System Hackers: Phreaks Earliest phone hackers? 1870’s teenagers 1920’s (first automated switchboards) • Mid-1950’s saw deployment of automated direct-dial long distance switches September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 5 US Telephone System (mid 1950’s) A dials B’s number Exchange collects digits, assigns inter-office trunk, and transfers digits using Single or Multi Frequency signaling Inter-office switch routes call to local exchange Local exchange rings B’s phone September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 6 Early 1970’s Phreaks John Draper (AKA “Captain Crunch”) – Makes free long-distance calls by blowing a “precise” tone (2600Hz) into a telephone using a whistle from a cereal box… – Tone indicates caller has hung up L stops billing! – Then, whistle digits one-by-one “2600” magazine help phreaks make free long-distance calls But, not all systems use SF for dialing…
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 7 Blue Boxes: Free Long Distance Calls Once trunk thinks call is over, use a “blue box” to dial desired number – Emits MF signaling tones Builders included members of California's Homebrew Computer Club: – Steve Jobs (AKA Berkeley Blue) – Steve Wozniak (AKA Oak Toebark) Red boxes, white boxes, pink boxes, … – Variants for pay phones, incoming calls, … September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 8 The Game is On Cat and mouse game between telcos and phreaks Telcos can’t add filters to every phone switch Telcos monitor maintenance logs for “idle” trunks Phreaks switch to emulating coin drop in pay phones Telcos add auto-mute function Phreaks place operator assisted calls (disables mute) Telcos add tone filters to handset mics – … The Phone System’s Fatal Flaw? In-band signaling! Information channel used for both voice and signaling Knowing “secret” protocol = you control the system September 7, 2005 CS161 Fall 2005 Joseph/Tygar/Vazirani/Wagner 9 Signaling System #7 “Ma Bell” deployed Signaling System #6 in late 1970’s and SS#7 in 1980’s Uses Common Channel Signaling (CCS) to transmit out-of-band signaling information – Completely separate packet data network used to setup, route, and supervise calls
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern