The DGS-3420 Series of next generation Layer 2+ Gigabit switches delivers performance, flexibility, security, multi-layer Qo S & access control, along with redundant power solutions for SMBs & enterprises. With high Gigabit port densities, Gigabit SFP & 10-Gigabit SFP+ support, & advanced software solutions, these switches can act as either departmental access layer devices or aggregation switches to form a multilevel network structured with backbone & centralized high-speed servers. Service providers can take advantage of the high SFP density switches to structure the aggregation of Fibre to the Building (FTTB) networks that they extend to the subscriber's sites. Easily deployed & simple to manage, the DGS-3420 can be virtually stacked with any switch that supports D-Link's Single IP Management (SIM) to form a multi-level network structured with backbone & centralized high-speed servers. The virtual stack can include units located anywhere on the same network domain, eliminating cable distance barriers, limitations of physical stacking, & the need for stack cabling. Alternatively, depending on whether linear or fault-tolerant ring stacking is implemented, users can use one or two 10-Gigabit SFP+ ports to create a physical stack. Switches in the stack are hot-swappable to minimize network downtime in case a replacement is required, eliminating single points of failure. Up to 12 units or 576 Gigabit ports can be configured for a stack using direct attached cables allowing high bandwidth & high port densities on the already cost efficient DGS-3420 Series. The DGS-3420 Series provides a complete set of security features including L2/L3/L4 multi-layer Access Control Lists & 802.1x user authentication via TACACS+ & RADIUS servers. The DGS-3420 Series offers extensive VLAN support including GVRP & 802.1Q VLAN to enhance security & performance. A robust set of L2/L3/L4 Qo S/ Co S solutions help ensure that critical network services such as