Cat 1
Voice Grade cable—not for data communications. Used for POTS (Plain Old Telephone Service).
This uses 2 pairs of unshielded twisted pair. Cat 2 U ses 4 pairs of unshielded twisted pair.
Good for data rates up to 4 Mbps (10 MHz). This rating is considered obsolete.
Cat 3
Uses 4 pairs of unshielded twisted pair. Good for data rates up to 16 Mbps. Three twists per
foot. Limited now to telecommunications and considered obsolete for data.
Cat 4
Uses 4 pairs of unshielded twisted pair. Good for data rates up to 20 Mbps. Considered obsolete.
Cat 5
Uses 4 pairs of unshielded twisted pair. Good for data rates up to 100 Mbps. This should no longer
be used. Cat 5e should be used instead.
Cat5e
Uses 4 pairs of unshielded twisted pair. Good for data rates up to 100 Mbps. The e in Cat 5e stands
for enhanced. This cable is capable of handling disturbances on all pairs caused by transmitting on
all 4 pairs simultaneously. Cat 5e is generally the same price as Cat 5.
Cat6
Uses 4 pairs of unshielded twisted pair. Good for data rates up to 1 Gbps (250 MHz).
Length limit = 228 ft. It should at least be used for "riser" cables (between floors).
Obviously not of much use within a truck but might be necessary for a compound.
T-568B is the common wire coding used today. When making new connectors you need to know whether wiring code A or B is in use.