ADTRAN ISU 128 user manual Fallback Menu Tree, =Protocol =V.34

Chapter 7. Protocol Options

When originating calls to unknown units, the ISU begins protocol selection based on the local call type. Data 64k is used for FALLBACK selected from Quick Setup menu. Upon connection at 64k call type, BONDING, V.120, and

PPPare attempted. If connection is not made at 64k, the ISU 128 attempts an- other call at 56k call type. If connection is made at 56k, then V.120, T-Link, and PPP are attempted. If connection is not made at 56k, then an audio call type is attempted, provided the ISU 128 with the V.34 modem option is used. If the ISU connects the audio call type, the V.34 protocol is attempted for V.34 com- patible modems. Once a call connects, if the protocol cannot be negotiated, the protocol is negotiated as specified by S11 register (default is DSTOP). If this protocol fails, the call is disconnected.

If FALLBACK fails to determine which protocol is running, the user has the option to select which protocol will run. Figure 7-6 illustrates the FALLBACK default settings.

3=CONFIG

1=Clear Channel

1=Netw. options	2=BONDING mode 1
2=DTE options	3=V.120
3=Protocol	4=V.34
4=Quick setup	5=V.110
5=Remote config
	6=DSU 57.6 ASYNC
	7=T-LINK
	8=SAP
		9=FALLBACK	1=Fallback Def.
	0=PPP asyn-sync

1=Clear Channel

2=BONDING Mode 1

3=V.120

4=V.34

5=V.110

6=DSU 57.6 ASYNC

7=T-LINK

8=SAP

9=PPP asyn-sync

Figure 7-6

FALLBACK Menu Tree

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