We all know Signal, Matrix, Telegram, SimpleX, etc… But if you can’t access the internet you can’t communicate. Pretty logic. But would it be possible, at least theoretically, to create an app that permits to message people even if the internet goes down?

It might be a dumb question I really have no idea to be honest.

  • Gayhitler@lemmy.mlEnglish
    1·
    7 days ago

    It’s not p2p but at least many years ago:

    SMS.

    If the Internet outage is local then the towers would still work and you’d be able to get texts. I went through a few storms where wired home internet was down, the towers weren’t giving me a data connection (no mobile web browsing or anything), but I was able to send and receive texts.

    If you really care about what you’re asking after, do what someone else said and get a radio license. It’s 150 year old technology and every time something happens radio operators pop up some kind of emergency communications or bridge to the internet through repeaters or something.

    • Mr. Zeus@feddit.orgEnglish
      0·
      8 days ago

      wouldn’t a cheap walkie-talkie be more practical in that situation?

      That’s not secure or encrypted

      • ERROR: Earth.exe has crashed@lemmy.dbzer0.comEnglish
        0·
        8 days ago

        You can encrypt a radio.

        Rattlegram is an app on iOS/Android that alllows converting text to audio and play it over your phone’s speaker

        Secure Space Encryptor (SSE) (known as Paranoia Text Encryption on iOS) is an Open Source app that can encrypt text.

        1. Use SSE to encrypt text
        2. Copy-Paste the Ciphertext to Rattlegram
        3. Sent it over the radio
        4. On the other end, use Raddlegram to turn the audio back to the ciphertext
        5. Use SSE to decrypt.

        Voila! Off-Grid Encrypted communications.

        Warning: Encryption over radio is illegal in many countries 😉 (but fuck the law lol, who cares)

        • Mr. Zeus@feddit.orgEnglish
          0·
          7 days ago

          You can encrypt a radio.

          Yes, but that requires you and the one(s) you’re communicating with to mod some radios and then to keep those radios secret, which won’t be easy once you start using them, especially in a situation like that where the government would probably be scanning those frequencies for exactly that

  • bad_news@lemmy.billiam.net
    0·
    8 days ago

    There used to be one years ago that used WiFi radios or Bluetooth or whatever so you could chat to people near you… I totally forget what it was called though.