Polycom 331 Owner's Manual page 22

Use the included phone cord and connect one end into the port on
the back of the phone labeled
any data port on your network (router,switch or wall jack).
Option 2: Connect Desk phones using your existing data network
then connect the phones to your computer
If you already have a computer using a wall data jack or
router/switch port,unplug the computer from the network, then
connect the phone using the steps in Option 1 Plug your computer
into the port on the back of the phone labeled
To your router or
wall jack
22
and connect the other end into
To your router or wall jack
To your PC