On successful call attempts that use ISDN CBC trunk groups, Call Detail Recording (CDR) records the NSF that the NSF IEs of the call specify. CDR refers to this information as the ISDN Network Service (INS). The value that is passed to CDR is the 3-digit equivalent of the NSF IE. The system also records NSF information for Facility Type 2 calls that use ISDN Call-by-Call trunk groups, 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 the 4-digit Interexchange Carrier (IXC) Code . CDR might not record the IXC properly if the dialed-code format differs from the US IXC code 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 also occurs for the user-defined Facility Type 2. However, the NSF recording occurs only if the NSF is available in the incoming SETUP message.