In a past life I taught data comms to college kids. And one of the things I taught was LAN (local area network) protocols. One of the famous protocols is CSMA/CD known by many names.
Why its outta control is that each actor is totally autonomous. Each entity on the LAN needs to figure out for itself whether it should be sending a message. It listens to the medium (carrier sense) to see if anyone else is talking. If there is silence it starts transmitting (only if it has data to send) at the speed of an electron wave propagating down wire (there are wireless versions amongst others).
This was the solution developed by universities under government funded grants for the original DARPA net that the internet we now have evolved from. Nevertheless, CSMA/CD is alive and well and still working on a LAN near you.
So CSMA/CD is what the government funded, a LAN, likely if you have a wireless network at home, like pretty much everyone in our neighborhood has, you are using CSMA/CD.
However the LAN developed by IBM, token ring, suffered a more tragic fate.
IBM developed their own LAN protocol, (also funded by the government with tax breaks and possibly grants). It was clunky, expensive, inefficient as hell and dictatorial. Basically you need to employ someone trained to manage your token ring, dedicate a computer to the task and it is controlling - basically, each computer is told when, by the master computer, it can talk and it prioritizes who can talk and when.
Unless you are a diehard IBM geek, which pretty much carries no cache, you wouldn't use it and if you did use it today you'd probably be laughed out of town by anyone who knows anything about data comms including those in red states voters. Basically token ring won the Darwin awards for LAN protocols.
I'll let you draw your own conclusions.
Why its outta control is that each actor is totally autonomous. Each entity on the LAN needs to figure out for itself whether it should be sending a message. It listens to the medium (carrier sense) to see if anyone else is talking. If there is silence it starts transmitting (only if it has data to send) at the speed of an electron wave propagating down wire (there are wireless versions amongst others).
This was the solution developed by universities under government funded grants for the original DARPA net that the internet we now have evolved from. Nevertheless, CSMA/CD is alive and well and still working on a LAN near you.
So CSMA/CD is what the government funded, a LAN, likely if you have a wireless network at home, like pretty much everyone in our neighborhood has, you are using CSMA/CD.
However the LAN developed by IBM, token ring, suffered a more tragic fate.
IBM developed their own LAN protocol, (also funded by the government with tax breaks and possibly grants). It was clunky, expensive, inefficient as hell and dictatorial. Basically you need to employ someone trained to manage your token ring, dedicate a computer to the task and it is controlling - basically, each computer is told when, by the master computer, it can talk and it prioritizes who can talk and when.
Unless you are a diehard IBM geek, which pretty much carries no cache, you wouldn't use it and if you did use it today you'd probably be laughed out of town by anyone who knows anything about data comms including those in red states voters. Basically token ring won the Darwin awards for LAN protocols.
I'll let you draw your own conclusions.
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