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Glossary

Technology evolves at a rapid-fire pace. That’s why we’ve built an easy-to-use glossary to help you better understand the terms, technologies and trends that impact your business.

Passive Optical Network (PON)

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What is a passive optical network?

A passive optical network (PON) is a network in which fiber-optic cabling, rather than legacy copper, is the medium carrying signals to the subscriber. It is described as passive because no active equipment (i.e., electrically powered) is required between the central office and the customer premises. Depending on where the PON terminates, the system can be described as an FTTx network, which typically allows a point-to-point or point-to-multipoint connection from the central office to the subscriber's premises.

In the case of a point-to-multipoint architecture, several subscribers (up to 32) can be connected to just one of the various feeder fibers located in a fiber distribution hub. This dramatically reduces network installation, management and maintenance costs.

Challenges when rolling out PON

The bandwidth boom is driving communications service providers (CSPs) to upgrade fiber-to-the-home (FTTH) architectures with next-generation passive optical networks in view of delivering gigabit and multi-gigabit broadband services. Technologies such as XGS-PON and 25G PON enable operators to increase network capacity, support higher-bandwidth applications and extend the value of existing fiber infrastructure. However, next-generation PON is often overlaid on legacy PON, making the network more complex and adding challenges for field crews when it comes to testing and ensuring quality of service and quality of experience.

With multiple wavelengths and PON technologies at the customer premises, frontline technicians must navigate new complexities:

  • Measuring upstream and downstream power
  • Testing more wavelengths
  • Identifying multiple PON technologies operating on the same network
  • Managing coexistence between legacy and next-generation PON services
  • Dealing with NG-PON2 and multiplexing

Learn more

To dig deeper into these challenges and explore solutions, including what to look for in a future-ready PON tester, learn more about the PPM-350D, EXFO's next-generation PON power meter.