Metro Access Convergence for Broadband Future Low Energy Consumption Networks

Problem statement: In study the impact of the optical technologies and infrastructures on the reduction of the carbon footprint maintaining high level of broadband to the end user is discussed. Approach: Authors analyze the main energy consumers in Core, Metro and Access Networks as well as the topology and the performaces of the EU FP7 SARDANA Project, a long reach full optical metro access convergent network. This permit to have a clear and innovative view on the topic of the green networks comparing commercial and on the edge solutions for the critical access segment. Three scenarios have been assumed with different uplink bandwidths: unlimited uplink in the CO, limited uplink of 400 Gbit sec^-1 and strong limitation of 100 Gbit sec^-1. Additionally, three different sizes of the access network with 100, 1,000 and 10,000 subscribers connected to a single CO have been considered. Results: Increasing the number of users and reducing the uplink bandwidth, the difference in energy efficiency between TDM and PONs and P-t-P FTTH networks increases. Conclusion: Authors conclude that in general, a SARDANA like network provides very good energy efficiency for both limited and unlimited uplink and for small and large networks.