4 ms·
>The Internet itself is "a zoo of endpoints on a shared medium", No, the shared medium in this case is referring the last part of the cable network where every
by pathseeker 7y ago
>The Internet itself is "a zoo of endpoints on a shared medium",
No, the shared medium in this case is referring the last part of the cable network where everyone in a neighborhood is transmitting effectively onto the same cable.
All it takes is a single device with a broken configuration to spew crap onto the wrong channels, taking down the whole neighborhood. https://en.wikipedia.org/wiki/DOCSIS#Physical_layer https://en.wikipedia.org/wiki/DOCSIS#Physical_layer
On the Internet it stops being a shared medium the minute it gets out of the cable network into fiber/ethernet switched+routed interconnections.
- ficklepickle 7y agoThat is a really good point and one I hadn't considered. Is it really that easy for a single device to take down a neighborhood? For example, could a bad actor trivially disrupt a node with a modified modem? I guess that would be difficult to defend against. I don't know enough about docsis to say if it has any protections against out-of-spec devices. I don't know why I'm surprised when things outside my area of expertise are fragile, considering things inside my area of expertise are fragile.
- lima 7y ago> Is it really that easy for a single device to take down a neighborhood? For example, could a bad actor trivially disrupt a node with a modified modem? I guess that would be difficult to defend against. Yes, similarly to how you could jam a radio frequency. Fortunately, this is rare and only ever happens due to hardware failures in modems.