Passive Optical Network vs Active Optical Network
Let me first briefly introduce the two networks.
Passive Optical Network (PON)
Passive optical network is a pure medium network, which avoids electromagnetic interference and lightning effects of external equipment, reduces the failure rate of lines and external equipment, improves system reliability, and saves maintenance costs. It is a long-term expectation of telecom maintenance departments. The light-free network is a point-to-multipoint optical fiber transmission and access technology. The downlink adopts the broadcast mode and the uplink adopts the time division multiple access mode. Topological structures such as tree, star, and bus can be flexibly formed, and only a simple optical splitter needs to be installed at the optical branch point. Therefore, it has the advantages of saving optical cable resources, sharing bandwidth resources, saving equipment room investment, fast network construction, and low cost of comprehensive network construction.
PON can also be subdivided into Broadband Passive Optical Network (BPON), Gigabit Passive Optical Network (GPON) and Ethernet Passive Optical Network (EPON). GPON) and Ethernet Passive Optical Network (EPON) are more common.
Active Optical Networks (AON)
Active optical network (AON) refers to the network in which the signal is transmitted from the central office equipment to the user distribution unit using photoelectric conversion equipment, active optoelectronic devices, and optical fiber and other active optical fiber transmission equipment during the transmission process. Active optical devices include light sources (lasers), optical receivers, optical transceiver modules, optical amplifiers (fiber amplifiers and semiconductor optical amplifiers), etc. Active optical network belongs to point-to-multipoint optical communication system, which consists of ONU, optical remote terminal OLT and optical fiber transmission line.
Difference between PON and AON
Application
In addition to the factors mentioned above, other factors need to be considered in practical applications. For example, when it comes to radio frequency deployment and video services, a passive optical network is more appropriate; if the target user has high network requirements or a large number of users (such as business customers or multiple residential buildings), choose a passive optical network. Active Optical Networks are more suitable. In addition to the differences mentioned above, there are other differences between the two networks. For example, industry standards, popularity, etc.
Signal distribution
The difference in the way of signal distribution is the biggest difference between the two. In a passive optical network, there is a situation where users share fiber bundles, while in an AON, each user has an independent fiber chain, and there is no shared bandwidth with each other.
In terms of coverage
PON typically only cover distances up to 20 kilometers, while AON can cover distances of about 100 kilometers. That is, users in a PON must be close to the incoming signal.
In terms of Cost
PON has no other power supply equipment except two ends, and requires less maintenance; while AON mainly performs network transmission through power supply equipment, so relatively speaking, the cost of AON is higher than that of PON.
In general, passive optical network and active optical network have their own characteristics. Whether it is to deploy a passive optical network or an active optical network, it needs to be completed according to the actual situation, and the two networks can be mixed in different situations. As the need for network interoperability and scalability continues to grow, future network architectures will allow free switching of fibers in passive optical networks and active optical networks.
