GPON is based on point-to-multipoint architecture

 

GPON stands for Gigabit Passive Optical Network. It is a type of high-speed network standard for Internet access, mainly used for broadband services over optical fiber. Here are the details of GPON and its main features:

 

1. Network Structure: GPON is based on point-to-multipoint architecture, which means that a single fiber optic cable can serve multiple locations using passive optical splitters. This is in contrast to the point-to-point model, where each location requires its own fiber optic cable.

2. OLT and ONT/ONU: OLT (Optical Line Terminal): This is a device located at the service provider's headquarters. It transmits data to multiple users and also collects data from users. ONT (Optical Network Terminal) or ONU (Optical Network Unit): This is a device located at the customer's premises. It receives data sent from the OLT. The terms ONT and ONU are sometimes used interchangeably, but ONT is usually customer facing and ONU can refer to a larger device that serves multiple customers in some situations.

3. Speed ​​and Efficiency: GPON offers asymmetric bandwidth with downstream rates of up to 2.5 Gbit/s and upstream rates of up to 1.25 Gbit/s. However, there are advancements and new standards that can provide even higher rates. The use of passive splitters in the network eliminates the need for power in the distribution network, reducing maintenance costs and improving reliability.

4. Wavelengths: GPON uses wavelength division multiplexing (WDM), which allows multiple signals with different wavelengths (colors) of light to be transmitted over a single optical fiber. Typically, two wavelengths are used, one for downstream data and one for upstream data.

5. Layer 2 Protocols: GPON uses Ethernet and TDM (Time Division Multiplexing) for data and voice services respectively. This makes it extremely versatile and allows a variety of services to be offered over a single infrastructure.

6. Distance and coverage: The GPON standard allows for coverage of up to 20 kilometers (about 12.4 miles) between the central office and the end user, making it suitable for both densely populated urban areas and large rural areas.