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Appendix
124
Explanation of terms
Exchange
connection
Method of setting up an external call. A distinction is made between manual,
automatic, destination and VIP exchange connection.
Exchange tone
Network operator’s dialling tone. Possibility to dial an external subscriber
number.
Call-waiting tone
Different signals are used for internal and external waiting calls.
Point-to-point
connection
This type of connection is also referred to as point-to-point operation (PP).
Point-to-point connection also allows you to connect a telephone system to
the S0 basic connection. It is possible to directly dial the destination
subscriber on this connection (refer also to DDI).
AOCD
Transferring charge information during the call.
AOCE
Transferring charge information at the end of the call.
Busy tone
This tone indicates that the line of the destination subscriber called is busy or
that there is no free line to establish the connection (lane occupied).
B channel
Refer to S0 interface
Clients
Computers or users who are connected.
DDI „Direct
Dialling-In”:
This is a call number that is added to the system’s call
number in order to reach the person required (also referred to as „direct-dial
number”). The DDI does not have to (but can) be the same as the subscriber’
internal number.
DHCP
Dynamic Host Configuration Protocol. DHCP servers assign a free IP address
to connected computers on start-up.
Service identification With ISDN, incoming calls are subdivided according to different services.
Service identification ensures that terminals only signal calls for which they
support service identification.
D channel
Refer to S0 interface
DNS
Domain Name Server. IP addresses are translated into names using a DNS.
Dynamic IP address IP address that is assigned by an Internet provider that is only valid for the
dial-in period. When dialling in again a new/altered IP address is usually
assigned.