The IEEE-1394 standard specifies the following maximum cable lengths:


Bus Type

Cable Type

Max Length

Speed Limitations

1394a

4-pin or 6-pin shielded TP copper

4.5 m

400 Mbps

1394b

9-pin shielded TP copper

4.5 m

800 Mbps

1394b

Unshielded TP

4.5 m

800 Mbps

1394b

Unshielded TP

100 m

100 Mbps

1394b

Glass optical fiber (GOF)

100 m

(Check with the manufacturer for speed/distance limitations).

1394b

Plastic optical fiber

50 m

(Check with the manufacturer for speed/distance limitations).


Some manufacturers sell cables that exceed the above specifications. In some cases, longer (e.g. 20m) cables can only be achieved by reducing the maximum bus speed to S100.