[ih] capacity v bandwidth

[Lawrence Stewart]

… Rummages around for information theory hat.

I don’t think I am alone in holding that things with digital interfaces should say “bandwidth” and things with analog interfaces should say “capacity”.

The Shannon-Hartley theorem is about the analog part of this.

In the digital domain, I think almost everyone uses “bandwidth” to talk about peak available bits-per-second and “capacity” to talk about usable bits-per-second under certain loads, queuing policies, and the like.

In the above, bandwidth is absolutely misused for digital circuits as compared to its analog meaning.  Capacity, unfortunately, has two meanings and they get muddled all the time.

Language evolves and non of this offends me.

Regarding Vint at Stanford I arrived there in September 1976, and by the time I was corresponding with Vint about using Ron Crane’s VDH line driver to get SU-ISL connected to the SUMEX IMP, he was back in Washington I think.

-L