Active Optical Networks (AON) and Passive Optical Networks (PON) and their differences

Active Optical Networks (AON)

Active Optical Networks (AON) are optical network that uses equipments such as splitters and switches that require electrical power. They consist of an optical fiber that runs from the service provider OLT(Optical Line Terminal)(see reference[1]) to distributing active splitter or switches and from there to the many customer's premises ONU(Opitcal Network Unit), with each customer having their own dedicated fiber connection. AONs use active equipment, such as switches and routers, to transmit and receive data between the service provider and the customer.

AONs are suitable for larger businesses and enterprises that require high-speed internet and customized network configurations. They offer a high level of security, as each customer has their own dedicated fiber connection, and they can provide higher bandwidth than PONs.

Picture below shows diagram of Active Optical Network.

 

Passive Optical Networks (PON)

Passive Optical Networks (PON) are  point-to-multipoint (P2MP) optical networks that uses passive equipment, such as splitters, to transmit and receive data between the service provider and the customer. That is the network has devices such as splitters that does not require electricity. They consist of an optical fiber that runs from the Optical Line Terminal(OLT) at the service provider's central office to a passive optical splitter, which divides the signal and distributes it to multiple ONU(Optical Network Unit) or ONT(Optical Network Terminator) at the customers' premises.

The following picture depicts a PON.

 PONs are suitable for residential areas and small to medium-sized businesses that require high-speed internet but don't need customized network configurations. They offer a lower cost and simpler installation compared to AONs, as multiple customers share a single fiber connection. However, PONs can be more vulnerable to security threats, as multiple customers share the same fiber connection.

There are various old and new PON implementation such as APON and BPON which are old protocols and the newer are the EPON(Ethernet-PON) and GPON(Gigabit-PON). The following picture illustrates the EPON and GPON protocols diagrammatically.

EPON:

GPON:

Differences between AON and PON

The primary difference between AON and PON is the use of active equipment that requires electrical power in AONs and passive equipment that does not require electrical power in PONs.

Another significant difference is the bandwidth capacity. AONs can provide higher bandwidth and are suitable for businesses and enterprises that require customized network configurations. PONs, on the other hand, offer lower bandwidth but are more cost-effective and easier to install.

 AON is more complex than PON. That is installation, maintenance and operation of AON is more involved than PON.

AON can provide longer range of service than a PON due to use of active devices in the network that amplifies the incoming signal to distribute to end points ONU.

Lastly, the security of AONs and PONs differs. AONs offer a high level of security, as each customer has their own dedicated fiber connection. PONs, on the other hand, can be more vulnerable to security threats, as multiple customers share the same fiber connection.

Conclusion

In conclusion, both AONs and PONs offer high-speed internet connectivity, but they differ in terms of bandwidth capacity, installation cost, and security. Service providers should consider their customers' needs and requirements to determine which technology is the best fit for their business.

References:

[1] Optical Line Terminal(OLT), its features and installation guide

[2] Optic Fiber Media Converter and Its Cost