D-20
Preliminary November 23, 1998
MultiVoice Gateway for the MAX— User’s Guide
Cables and Connectors
Serial WAN cabling specifications
For the Host/BRI module
Each ISDN BRI line provided by the Host/BRI module (MX-SL-8BRIT) must end in a 100
Ω
termination. The maximum cable distance between the Host/BRI and its termination is 3280
feet (1000 m). You can install the local ISDN BRI device anywhere along the length of the
cable. Use only cable specifically constructed for ISDN BRI S interfaces.
Cable length requirements
Table D-19 specifies the recommended maximum length of the cable between the MultiVoice
Gateway and the serial host equipment. Longer distances at the specified data rates are
possible when you use terminal timing, and still longer distances are supported by the
installation of the Ascend RPM, a hardware device that provides an extended distance
high-speed link between the MultiVoice Gateway and the serial host equipment.
Serial WAN cabling specifications
The MultiVoice Gateway unit’s serial WAN interface supports nailed-up connections to the
WAN. Data packets from the MultiVoice Gateway unit’s bridge/router module can use this
interface, but bit streams from devices connected to the MultiVoice Gateway unit’s serial host
ports cannot.
The MultiVoice Gateway unit’s serial WAN port is compatible with the following two
electrical standards:
•
V.35
•
RS-449/422
In the cable wiring tables that follow, the MultiVoice Gateway is the Data Terminal Equipment
(DTE) that connects to a Data Circuit-Terminating Equipment (DCE) device through its serial
WAN port. The MultiVoice Gateway receives the Send timing and Receive timing clocks from
the DCE device.
Table D-19.Cable length requirements
Max cable length
Serial data rate
25 feet
3 Mbps
75 feet
2 Mbps
150 feet
512 Kbps
