Figure 1 illustrates typical GEPON or any PON with CO located OLT and multiple ONUs and ONTs for multiple subscribers. Data is being delivered through the single fiber from OLT to the passive optical splitter from where it is being divided to separate signals that are supposed to go to the ONUs/ONTs. Signal is being transmitted downstream, using TDM and being broadcasted to all of the ONUs and ONTs, where they pick up data that is intended just for them. Encryption might be one of security measures that will ensure data safety. For the upstream transmission, TDMA is being used. Both directions of data transmission are using different wavelengths in order to prevent data collision. Figure 2 is showing downstream and upstream broadcasts.
P2MP features are being implemented in the PON, giving it advantage with positive equipment, reduced amount of transceivers, high data rates, fewer feeder fibers. PON is optimal for scenarios where P2P costs for maintenance and fiber installation are too high. PON is offering signal coverage of up to 20 km with possible scalability
Figure 1. Generic PON.
Another option for reducing costs using PON is the implementation of the sleep mode. While there are two options of doing that, both of them ensure quick wake-up for the PON, ensuring there would be no disruptions. First option is a transmitter sleep mode, where CO equipment will be saving energy. Second option is putting transmitter and receiver to the cyclic sleep mode. Both options give potential energy savings without data transmission delays.
Typical active component splitter consists of dozens of active parts like regenerators, repeaters, amplifiers. PON based passive optical splitter is using longer-lived passive components with lover cost. Meanwhile the passive splitter is doing the same job of splitting signal downstream and combining it upstream.
To get real life examples of products you can also check our product pages for:
GEPON OLT: https://www.ad-net.com.tw/index.php?id=197
GEPON ONU’s: https://www.ad-net.com.tw/index.php?id=176
PLC splitters: https://www.ad-net.com.tw/index.php?id=815