ISO 11898-2 Constraints: Max bus length is inversely proportional to bit rate. At 1 Mbps, max length is typically 40m. Max stub length is 0.3m. Max nodes is typically 30 without repeaters.

Propagation Delay: Signals travel at $\approx 5 \, ns/m$. Total loop delay (Node A $\rightarrow$ Node B $\rightarrow$ Node A) must be strictly less than the bit time ($T_{bit} = 1 / f$).

Reflections: Stubs cause impedance mismatches. Un-terminated stubs should be kept as short as possible to prevent ringing. $L_{stub} < \frac{0.1 \times v_{prop}}{f_{knee}}$.