ADTRAN ISU 2x64, User Manual

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Chapter 6. Configuration
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ISU 2x64 Dual Port ISDN Service Unit User Manual 61200051L1-1D
The primary usage for SAP is general purpose asynchronous rate
adaptation in a dial-up or leased environment. SAP only oper-
ates on a 64 kbps data link. Figure 6-21 illustrates the menu path
for selecting
SAP .
FALLBACK
The FALLBACK asynchronous rate adaptation protocol provides
the capability to automatically establish calls with other ISDN
terminal adapters and Switched 56 DSUs, as well as other ISUs
using a single configuration. The ISU 2x64 must be optioned as
follows for
FALLBACK operation:
1. Any asynchronous bit rate up to 115.2 kbps which is support-
ed by the DTE.
2. Flow control must be enabled and supported by the DTE.
FALLBACK supports the following protocols based on the Call
Type: BONDING mode 1, V.120, and T-Link. Figure 6-21 illus-
trates the menu path for selecting
FALLBACK .
When answering calls, the ISU 2x64 uses the incoming call type
to determine which rate adaptation protocols to support.
Table 6-A
Rate Adaptation Protocols
Call Type
Rate Adaption Protocols
Supported
Typical Units Supported
Data 64 k Bonding mode 1 ISUs
V.120 ISDN TAs
PPP async-sync PPP compatible bridges/routers
Data 56 k BONDING mode 1 ISUs
V.120 ISDN TAs
PPP async-sync PPP compatible bridges/routers
T-Link 2-wire Switched 56 DSUs