What's New in FIVE

	What's New in FIVE

Digital Networking Unit - SONET (DNU-S)

The Digital Networking Unit - SONET (DNU-S) is a new peripheral unit on the Switching Module (SM-2000). The DNU-S is a high capacity digital trunk termination vehicle which can support up to 8064 digital trunks via a new SONET STSX-1 interface. In 5E10, the DNU-S only supports a intra-office STSX-1 interface limited to 900 feet.

Each STSX-1 interface is 51.84 Mb/s and can support 672 digital trunks. A single DNU-S unit can support up to 12 STSX-1 interfaces. A single SM-2000 can support up to 18 STSX-1 interfaces with a maximum of 10,752 trunks in 5E10 or up to 24 STSX-1 interfaces with a maximum of 16,128 digital trunks as of 5E11.

The DNU-S interface to the SM-2000 Time Slot Interchange (TSI) is via new optical Peripheral Control and Timing (PCT) links. These links are 65.536 Mb/s and replace the Peripheral Interface Data Bus (PIDB) and Peripheral Interface Control Bus (PICB) interfaces currently utilized by SM peripherals.

The DNU-S interface to the network is via electrical STS-1 (STSX-1) links. The STSX-1 interface is a standard SONET interface and as such is compatible with transmission equipment that supports the STSX-1 interface, including the Lucent Technologies Digital Access and Cross Connect System IV-2000 (DACS IV-2000), the Lucent Technologies Dual Digital Multiplexer - 2000 (DDM-2000), and SONET transmission equipment from other vendors.