ADTRAN 1200063L1, Manual

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61200063L1-20 DSU III TDM User Manual 1-1
Chapter 1
Introduction
PRODUCT OVERVIEW
The ADTRAN DSU III TDM (time division multiplexer) enables the user
to run four DTE ports over a single 56/64 kbps Digital Data Service (DDS)
circuit. One communications link is shared by up to four DTE devices by
enabling each DTE to use the path exclusively at regular intervals. In this
way a circuit capable of a relatively high information transfer rate is sub-
divided into time slots to provide a number of lower speed channels.
Figure 1-1 on page 1-2 shows an example of a typical application using the
DSU III TDM on a 64 kbps network. Each of the four DTE devices is al-
lowed a portion of the dedicated circuit, not exceeding the allowable band-
width of 60.8 kbps.
The major capabilities of the DSU III TDM include:
• 56/64 kbps leased line point-to-point DDS operation
• Four independent DTE ports
• Synchronous or asynchronous operation on all ports
• Single port operation
• Automatic remote configuration for critical options
• Optional dial backup capability (4-wire Switched 56, 2-wire Switched
56, ISDN, or V.32 bis)
• Extensive test functions for testing of DTE & Loop interfaces
• Extensive status monitoring