Intel ER8100STUS - Express 8100 Router, Reference Manual

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Reference.bok : Chapter04 24 Wed Apr 22 10:58:08 1998
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ISDN Numbering and Addressing
ISDN Services
Call Hold (HOLD)
Allows you to interrupt a call and return to it later.
Line Hunting (LH)
Allows incoming calls to a specific number to be distributed over a group of
lines.
Call Forwarding (CF)
Causes an incoming call to be sent to another number.
Call Transfer (CT)
Allows either the calling or called party to transfer the call to a third party.
Add on Conference Call (CONF)
Allows additional subscribers to be added to a call to form a conference.
Three-Party Service (3PTY)
Allows you to switch between two calls.
Advice of Charge (AOC)
Gives call charge information.
ISDN Numbering and Addressing
Introduction to ISDN
numbering
Like the Public Switched Telephone Network (PSTN), Integrated Services Dig-
ital Networks (ISDNs) uses Directory Numbers (DNs) to identify subscribers.
The International Telegraph and Telephone Consultative Committee (CCITT) a
numbering plan for ISDN (Recommendation E164) which specifies how num-
bers should be constructed within telephone networks. E164 includes the existing
plan E163 for the PSTN—both ISDN and PSTN numbers can therefore be allo-
cated out of the same range of numbers.
Each ISDN directory number specifies a point of connection to the network (an
ISDN line). Each line can, however, support more than one terminal—see
“BRA
and PRA Numbering”, p. 26
E164 format
The number consists of a maximum 15 digits and is divided up in the following
way:
Country Code (CC)
This consists of 1-3 digits.
National Significant Number (NSN)
This consists of between 12-14 digits. This is sub-divided further into a:
■
National Destination Code (NDC)
■
Subscriber Number (SN)
In Denmark, for example, the NSN is 8 digits long; NDC = 2 digits and the
SN = 6 digits.