Interoperability is an ability of network successfully perform its tasks without any problems, when network equipment is manufactured by different manufacturers. Interoperability is encouraged by possibility of network service consistency across manufacturers. It is also encouraged by customers, since it simplifies the installation process. Different PON products are able to provide uniform implementation of the system using equipment from various vendors. Optical Network Units (ONUs) / Optical Network Terminals (ONTs) and Optical Line Terminals (OLTs) have competing quality-to-price ratio due to competition between manufacturers.

Apart from reduced costs and larger selection of equipment, interoperability offers benefits of expanding PON technologies and creating long-term platform.

Tests for interoperability are hosted by the Full Service Access Networks (FSAN) Interoperability Task Group and the International Telecommunication Unit (ITU). The purposes of tests might differ from time to time. Organisations might be testing:

• Support of different broadband data services over BPON while using equipment from multiple manufacturers;

• Verification of the conformance meeting ITU-T standards;

• Voice signal transportation between different interfaces of ONTs and OLTs;

• Evaluation of the voice, video, and data services transmission meeting QoS standards;

• Olts and ONUs behaviour in the events of failure and error;

• Symmetric 10G-EPON products interoperability

Resolving the interoperability issues might be challenging. Most common ways of doing that will be described in following articles. Stay Tuned!