ADTRAN ISU 2x64, User Manual

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Chapter 1.Understanding ISDN and the ISU 2x64
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ISU 2x64 Dual Port ISDN Service Unit User Manual 61200051L1-1D
The ISU 2x64 features two RS-530/EIA-232 DTE interfaces and
two RS-366 dial interfaces (see Figure 1-1). An RS-530/EIA-232-
to-V.35 adapter is available to support V.35 DTE interfaces. Syn-
chronous data transfer rates from 2400 bps to 128 kbps and asyn-
chronous rates from 1200 bps to 115.2 kbps are supported on a
single DTE interface. Synchronous data transfer rates from 2400
bps to 64 kbps and asynchronous rates from 1200 bps to 57.6 kbps
are supported when using two DTE interfaces. For speeds over 64
kbps using a single DTE interface, the industry standard BOND-
ING protocol aggregates the two 64 kbps B channels for a maxi-
mum of 128 kbps.
Dialing from the ISU 2x64 is accomplished in a variety of ways:
• Dialing manually from the front panel
• Dialing automatically from stored numbers
• Dialing through two RS-366 parallel dial interfaces (as in vid-
eo conferencing applications)
• Dialing over the DTE interfaces using AT command
• V.25 bis in-band dialing (used in applications such as LAN/
WAN bridging)
• Dialing when DTR is asserted (some Bridge/Routers raise
DTR when bandwidth on their dedicated line is exceeded)
Figure 1-1
ISU 2x64 Rear Panel
DTE#2
RS530A / RS232
RS366 DIALING PORT
MAINTENANCE
ISDN IFC POWER
OFF
ON
DTE#1
RS530A / RS232
RS366 DIALING PORT