POL or passive optical local area network is an inexpensive solution to connect different devices to the internet. POL was first time introduced in 1987 by British Telecommunications.
There are 3 major components of POL that are:-
- Optical Line Terminal (OLT)
- Optical Splitter
- Optical Network Terminal (ONT)
OLT or optical line terminal is placed in main exchange i.e. at ISP office. OLT is connected to the optical splitter through a fiber optics cable. The connection between the optical splitter and ONT (Optical Network Terminal) is also made through fiber optics cable. The reason for using fiber optics cable is that its data transfer speed is much higher than copper wire. Copper wire can only transfer data within 100 meters while fiber optics can transfer data to a distance of 20 km.
The splitter can transfer data without electricity. In a big organization, the optical splitter can be placed on the ground floor of the building. While for small business or home use splitters are placed in a public place also.
The optical network terminal (ONT) looks like a modem or router. The ONT can be connected to multiple devices e.g. laptop, PC, workstation, smartphone etc. You can connect your devices through copper wire or RJ-45 cable to the ONT. The ONT can convert fiber optics signals to the RJ-45 cable compatible signal type.
Note that the data transfer speed from OLT to ONT is fast as compared to the data transfer speed from ONT to devices. This data transfer speed is fast where fiber optics are used as compared and slow speed where the copper wire is used.
POL can connect to different locations like offices, homes, organizations. So there are different types of connections made. Some connection types are:-
- Fiber to the building (FTTB)
- Fiber to the curb (FTTC)
- Fiber to the home (FTTH)
- Fiber to the neighborhood (FTTN)
Features of passive optical local area network (POL)
- POL can be used to give high-speed internet to large organizations
- It is economic to use POL
- The efficiency of POL is much better than copper wire
- The low energy is used to make POL network
- It is easy to set up and maintain
- The security is high than traditional network
- High bandwidth can be achieved using this network
- One optical splitter can be connected to 16, 32 or 64 ONT
- POL is less prone to faults and damage
Examples of passive optical local area network (POL)
The POL is used in:-
- University Campus
- Large organizations