Derater,
The term NJPJ must be directing towards "Network Jacks / Phone Jacks".
Most commonly, the LAN will be an Ethernet based LAN with a speed of 100 MBPS.
Currently, the most common design would use 4 pair CAT-5 UTP for "Data" and 4 pair CAT-3 UTP for "Voice" and "Analog [MODEM]".
The entire design topology [AKA LAN Map] will need to be reviewed if you plan to pull cables and terminate.
Ask the Client to request a meeting with their Network Administrator or designer [AKA the Netgeek or "Ol' Dorito Breath"] to discuss specs and locations for equipment and outlets.
There are several types of cable specs used, so find out which one is required.
For UTP, the most basic for anything above 10 MBPS is plain CAT-5. Above this is CAT-5e [and other varieties of enhanced cables], then CAT-6.
After you get more info from the client, please post more to this thread so we can help make sense of things [plus add some suggestions].
Good luck!
Scott. S.E.T.