The HP BLc 4X QDR IB Switch for HP Blade System c-Class is a double wide switch for the HP Blade System c 7000 enclosure. It is based on the Mellanox Infini Scale IV technology. The QDR IB switch blade has 16 downlink ports to connect up to 16 server blades in the c 7000 enclosure, & 16 QSFP uplink ports for inter-switch links or to connect to external servers. All ports are capable of supporting 40 Gbps (QDR) bandwidth. A subnet manager has to be provided; see the paragraph on subnet managers for more details. The QLogic BLc 4X QDR IB Switch for HP Blade System c-Class uses the QLogic True Scale ASIC architecture designed to cost-effectively link workgroup resources into a cluster or provide an edge switch option for a larger fabric. Customers have the ability to internally or externally manage the modular IB switch.