Currently, passive optical networks are the only technology capable to carry large amounts of data in a transparent way, with great scalability in the structure and low maintenance costs. Once these networks are deployed, professional and domestic users will have at their disposal an optical connection all the way to their homes or offices. This will cover all the band width requirements of increasingly demanding applications, such as file exchange, online gaming, and multimedia content.

The NRG research group of the Universidad Autónoma of Madrid and the Eindhoven University of technology propose passive optical network architecture that includes not only the design of the physical architecture and electronic components but also the access mechanisms to the shared medium, achieving a global view of the architecture and its potential performance.

In this proposal, published in the IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS (IEEE J SEL AREA COMM (2009). 27(2):143-154), every user is assigned a personal code that is used to transmit information in private and with no risk of interference with the information of other users that simultaneously transmit with their respective codes. The optical signals are combined in a location near to their homes and travel together through the same optical motorway towards the main network.

Nevertheless the interference at an optical level can cause problems when many users transmit simultaneously. For this reason, it is necessary to manage the users and at which point in time they access the common motorway to avoid crashes between different users with the consequent destructive interference.

The management algorithm proposed by the researchers requires each user to follow three separate steps: measure the level of activity in the common fibre, forecast the future level of such activity and accommodate the user traffic until the best time to access, this means the point of time with the least probability interfering with other transmissions in the common fiber.