Featuring a 10Gbps backplane, populated with near-terabit switching capacity network interface cards and front-connector line cards, the F61 is a medium-sized shelf optimized as an Optical Line Termination (OLT) for fiber access networks. It can be populated with any combination of xDSL, fiber and VoIP line cards, to provide Ethernet aggregation, all with a non-blocking internal architecture to maximize bandwidth availability. The F61 is a member of the Hi-FOCuS MSAN family, which has a strong track record of serving Tier 1 carriers and their millions of subscribers.