Administrator's Guide

Features and technical reference
555-233-5061634 Issue 5 October 2002
The treatment for an incoming call is selected based on the first 3 columns in the
ICHT on the ISDN Trunk Group screen. When the attributes of an incoming call
match these specifications, the call is treated according to the corresponding
following 4 columns. If an incoming call matches more than one set of
specifications, the most restrictive case applies. The following table lists the
possible cases from most restrictive to least restrictive.
Call detail recording
On successful call attempts using ISDN Call-By-Call trunk groups, CDR records
the NSF specified by the call’s NSF IE. CDR refers to this information as the
ISDN Network Service (INS). The value passed to CDR is the 3-digit equivalent
of NSF IE. NSF information for Facility Type 2 calls (used with ISDN-Pri
Call-by-Call trunk groups) also is recorded if the NSF is available in the incoming
SETUP message.
If an outgoing Call-by-Call Service Selection call uses an interexchange carrier
other than the presubscribed common carrier, CDR records the 3-digit or 4-digit
Interexchange Carrier Code (IXC). CDR may not record the IXC properly if the
dialed-code format differs from the US IXC formats.
When a Call-by-Call Service Selection call is rejected because of a UAP, CDR
records the cause as an ineffective call attempt. The NSF recording takes place
also for the user-defined Facility Type 2. However, the NSF recording takes place
only if the NSF is available in the incoming SETUP message.
Service /
Feature Called Len Called Number
Most
restrictive
Specified Specified x leading digits specified
Specified Specified y leading digits specified, where y <
x
Specified Specified not specified
Specified Not specified not specified
“other” Specified x leading digits specified
“other” Specified y leading digits specified, where y <
x
“other” Specified Not specified
Least
restrictive
“other” Not specified Not specified