An OLT (optical line terminal), also known as optical line termination, acts as the endpoint hardware device in a passive optical network. The OLT contains a central processing unit (CPU), passive optical network cards, a gateway router (GWR) and a voice gateway (VGW) uplink cards. It can transmit a data signal to users at 1490 nanometers (nm). That signal can serve up to 128 ONTs at a range of up to 12.5 miles by using optical splitters.