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Netheads vs. bellheads redux: the strange victory of SIP over the telephone

devever.net published 2023-01-2711 min read

How much do you know about how the PSTN (that is, the public telephone network) works? At some point long long ago, it was signalled using in-band frequencies, which facilitated the infamous phreaking using so-called “blue boxes”. This led to a switch to out of band signalling, ultimately culminating in something…

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History & Retro ComputingNetworking & Internet2023

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