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Chapter 7. Protocol Options
54
ISU 128 User Manual
61202.029L2-1
FALLBACK
The
FALLBACK
asynchronous rate adaption protocol provides the capability
to automatically establish calls with other ISDN terminal adapters, Switched
56 DSUs, V.34 modems (optional), as well as other ISUs using a single config-
uration. To communicate with analog modems, the ISU 128 with V.34 modem
option (part numbers 1202029L3) must be used.
The ISU 128 must be optioned as follows for
FALLBACK
operation:
•
Any asynchronous bit rate up to 115.2 kbps which is supported by the
DTE.
•
Flow control must be enabled and supported by the DTE.
FALLBACK
supports the following protocols based on the call type: BOND-
ING Mode 1, V.120, T-Link, and V.34.
When answering calls, the ISU 128 uses the incoming call type to determine
which rate adaption protocols to support. See Table 7-A for the call type and
the supported rate adaption protocols.
Table 7-A
Rate Adaption Protocols
Call Type
Rate Adaption
Protocols Supported
Typical Units Supported
Data 64k
BONDING Mode 1
ISUs
V.120
ISDN TAs
PPP
PPP compatible bridges/routers
Data 56k
V.120
ISDN TAs
T-Link
2-Wire Switched-56 DSUs
PPP
PPP compatible bridges/routers
Speech or Audio
V.34
V.34 compatible modems
Содержание ISU 128
Страница 11: ...Table of Contents vi ISU 128 User Manual 61202 029L2 1 ...
Страница 15: ...List of Tables xii ISU 128 User Manual 61202 029L2 1 ...
Страница 23: ...Chapter 1 Understanding ISDN and the ISU 128 8 ISU 128 User Manual 61202 029L2 1 ...
Страница 29: ...Chapter 3 Installation 14 ISU 128 User Manual 61202 029L2 1 ...
Страница 43: ...Chapter 6 Configuration 28 ISU 128 User Manual ...
Страница 61: ...Chapter 6 Configuration 46 ISU 128 User Manual 61202 029L2 1 ...
Страница 73: ...Chapter 7 Protocol Options 58 ISU 128 User Manual 61202 029L2 1 ...
Страница 85: ...Chapter 9 Dial Options 70 ISU 128 User Manual 61202 029L2 1 ...
Страница 91: ...Chapter 10 Remote Configuration 76 ISU 128 User Manual 61202 029L2 1 ...
Страница 101: ...Chapter 12 Specifications 86 ISU 128 User Manual 61202 029L2 1 ...
Страница 107: ...Appendix A AT Commands 92 ISU 128 User Manual 61202 029L2 1 ...
Страница 111: ...Appendix B Current Status Messages 96 ISU 128 User Manual 61202 029L2 1 ...
Страница 121: ...Appendix C Status Buffer Messages 106 ISU 128 User Manual 61202 029L2 1 ...
Страница 135: ...Appendix E Connector Pinouts 120 ISU 128 User Manual 61202 029L2 1 ...
Страница 145: ...Glossary 130 ISU 128 User Manual 61202 029L2 1 ...