The SpectraLink 6300 MCU is the processing center for large-scale deployments. It consists of at least one primary shelf and up to 19 expansion shelves and can support up to 3,200 users. The primary shelf contains the system controller card that manages call processing for the wireless network. Telephone line and Base Station connections are made to an Interface Module. Each module supports 16 Wireless Telephones and six Base Stations, for up to 160 Wireless Telephones and 60 Base Stations per shelf. Multiple sites can be networked using T1 circuits between up to 18 remote shelves and the main site.

Remote Networking
The SpectraLink 6300 MCU supports up to 18 remotely networked shelves connected to a centralized System Controller. A networked system allows users the ability to roam throughout multiple buildings when the distance between the MCU and Base Station is farther than 6,000 feet, or there is no way to effectively run the connecting cable.

T1 circuits are used to provide the connection from the System Controller to each remote expansion shelf. A Channel Service Unit (CSU) must be provided by the customer at each end of the T1 circuits if the public-switched network is utilized for the T1 connectivity. One full T1 circuit is required for the first five Interface Module cards in a remote expansion shelf. A second full T1 circuit is required if six or more Interface Module cards are deployed in the remote expansion shelf. T1 Remote Modules are required to interface the T1 circuits to the SpectraLink 6300 MCU shelves. One T1 Remote Module is required within the remote shelf and one needs to be placed in either the primary or an expansion shelf at the local location. If a PBX is not utilized at the remote site, the remote shelf is only required to connect and network the Base Stations using Interface Modules. If a PBX is available at the remote location, a T1 circuit is still required for the remote shelf in order to fully network the SpectraLink 6000 System.