3.4 Call Sequence
3.4.1 Direct call setup sequence
CES | NCS | FELCOM |
Call to
subscriber
Reply from subscriber
SES RQ
CESI
Ch. assignment req. SU
Channal assignment SU
NCSI
HSUB
Scr. vec. ack SU
HSUB
Fill in SU
CES connect SU
HSUB
Access req. SU
NCSA
Service addr. SU scr. vec. advise SU HSUB
Ret. carrier ID SU
HSUB
HSUB
SES connect SU
Calling operation (DTR ON)
DSR ON
CTS/DCD ON
Figure 5 Direct call setup sequence
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