Line coding and bit time

Data

Bits

Code

Link

Rate R

Playback

Duration

Spacebar: play or pause. R: reset. Duration refers to 1 Mbps; the cursor always advances at the same speed, so at higher rates the frame finishes sooner.

Bit time 1/R

Bits L

Transmission L/R

Sending

–

Each bit occupies the link for a fixed time, the bit time. Transmission delay is the sum of those intervals: changing the line code changes the waveform, changing R narrows each bit. The on-screen width is not proportional to real time (1 Gbps is a thousand times faster than 1 Mbps, not four); the cards give the exact values.