EC researchers demo multi-gigabit fibre-to-the-home
Running rings around copper broadband
European Commission-funded researchers have declared a high speed broadband research project a success, stating that the “Sardana” project (Scalable Advanced Ring-based Passive Dense Network Architecture) has demonstrated the feasibility and robustness of 10 Gbps fibre-to-the-home networks.
The project, which was supported by €2.6 million from the Commission, also demonstrated that the higher speeds it describes are achievable using off-the-shelf components.
The main architectural change proposed by the Sardana researchers is to fan-out end user connections closer to the home, and using wavelength division multiplexing (WDM) to increase the capacity delivered to the fan-out nodes. A PON environment such as is being used by Australia’s National Broadband Network serves as many as 32 households from a node, which limits the capacity that can be delivered to the end user (although the NBN is designed to start at 100 Mbps, and has been demonstrated at an end-user speed of 1 Gbps).
Serving nodes from a fibre ring also makes the network more robust, according to the Sardana researchers, since connectivity should be able to survive a break in the ring.
More encouragingly, the Sardana pilot demonstrated symmetrical high-capacity connections, rather than the lingering asymmetry that inhibits most current architectures.
“Using WDM on the ring means we can multiply bandwidth by 40 wavelengths so individual users can enjoy 1 Gbps: not just in one direction, but in both directions, both upstream and downstream,” says Professor Josep Prat of the Universitat Politècnica de Catalunya, coordinator of the project.
“This could open the door to entirely new applications that are simply not possible today, such as high definition video conferencing.”
The trial network included lab tests by Tellabs, a field trial in Brittany, and a demonstration at the FTTH Council in Milan. The tests showed that the Sardana architecture could serve as many as 4,000 users with symmetrical 300 Mbps connections up to 20 Km from the main ring, or up to 250 users 100 km from the main ring, with 10 Gbps / 25 Gbps asymmetrical services. ®