10.55.4.4. COT/COP 
- If a local announcement is to be supplied from an incoming allocated circuit, the COT parameter "ANNC" is to be set. The SIU tone is then applied. This tone was configured by assigning the value LOCANN in the AMO ZAND:TONES (incoming allocated circuit). With the COP DTN, the analog trunk sends a tone to the remote office. You can configure which tone is sent with the COT parameter (NTON, ONAS, DTNI, DTNE)
- For analog trunk line circuits reserved for reverse dialing in incoming traffic, the COT parameter "USD" must be set for unrestricted suffix-dialing. This is not necessary for outgoing step by step dialing in tie trunk traffic.
- For further dialing after ANSWER, the COP parameter "SEDL" must be set