The Cisco Nexus 3550-F Fusion is built around a unique modular architecture that scales with your network. Three-line card bays provide the flexibility to grow and change connectivity options over time, while two internal module bays allow the device to be upgraded with expanded functionality, adding new capabilities and extending the useful life of the product. The 3550-F architecture is shown in the figure below. At the heart of the architecture is a high-density layer 1 matrix switch. This matrix switch provides low latency programable 10GbE connectivity between all modules.