Which network component is referenced when describing equipment room expansion to accommodate an additional cross-connection?

• A. Horizontal cross-connect (HC)
• B. Vertical distribution unit
• C. Backbone switch
• D. Central office interface

Answer: (A)

The key idea is the horizontal cross-connect. This is the point inside the equipment room where horizontal cabling from the work areas is cross-connected to backbone cabling or to downlink equipment. When you expand the equipment room to support an additional cross-connection, you’re increasing the capacity of the horizontal cross-connect—adding more patch panels or cross-connect hardware to handle more ports and connections.

The vertical distribution unit, by contrast, handles vertical cabling runs between floors and isn’t about adding more cross-connections in the equipment room. A backbone switch is a network device that interconnects core network paths and isn’t the mechanism used to expand the cross-connect capacity in the equipment room. The central office interface is the boundary to the service provider’s network, not the internal cross-connection expansion point.