The OLT serves as the central hub in a PON system, connecting the service provider's network to the subscriber's premises. Its primary function is to aggregate and distribute data traffic to and from multiple Optical Network Units (ONUs) or Optical Network Terminals (ONTs) within the. An optical line termination (OLT), also called an optical line terminal, is a device which serves as the service provider endpoint of a passive optical network. In this article, we will discuss Optical Line Terminal (OLT), its definition, features, and functions. So, let's get started with a basic introduction. Whether you are using high-speed internet at home, watching IPTV, or running cloud-based.