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Inband signalling was the way long distance trunk lines worked back in the MF signalling days decades before ISDN D channels and SS7 and all that. A fun topic
by VLM 7y ago
Inband signalling was the way long distance trunk lines worked back in the MF signalling days decades before ISDN D channels and SS7 and all that.
A fun topic to google for is what and how the 2600 Hz signal worked.
- rusk 7y agoDidnt some guy figure out how to get free phone calls using a cheap whistle from a cereal box :-)
- jasonjayr 7y agoCaptain Crunch!
- CapitalistCartr 7y agoJohn Draper https://en.m.wikipedia.org/wiki/John_Draper https://en.m.wikipedia.org/wiki/John_Draper
- eskaytwo 7y agoAnd Wozniak had his blue boxes
- dylan604 7y agoThe book "Exploding The Phone" goes into all of these stories and much more. If you ever wanted to know about how and why the analog phone system was so hackable/phreakable, this book is for you. [0] http://explodingthephone.com/ http://explodingthephone.com/
- derekja 7y agoWow, don't know how I missed that book. Looks great!
- Piskvorrr 7y agoYes, that's the most famous application. As to why it worked...that's the more interesting story IMHO.