T1 trunk protocols reference

The following properties are provided for voice card T1 trunk protocols. Properties are in alphabetical order and identified by card type.

If you use a DP6409 card, two trunks are available with this card; therefore, the total number of channels available will be double the number stated in the supported voice cards section (see related topics below).

			Applicable Cards
Protocol	Description	Channels Available	DP	DT
ISDN	Integrated Services Digital Network (ISDN) is a signaling variant used with the T1 or E1, reserving a single data channel on each multiplexed line for signaling information.	23
Non-ISDN	Applies to CAS or Robbed Bit Signaling (RBS), which are signalling variants used with the T1 or E1, reserving a single data channel on each multiplexed line for signaling information.	24
NFAS	NFAS D. This is a variant of ISDN used with T1 where a single D-channel is used to service up to 10 x T1 lines. Use NFAS D when the T1 is part of an NFAS group and this T1 contains the D-channel.	23
	NFAS Backup. This is a variant of ISDN used with T1 where a backup channel, not necessarily the D-channel, is used to service up to 10 x T1 lines. Use NFAS Backup when the T1 is part of an NFAS group and this T1 contains the backup D-channel.	23
	NFAS None. A non-facility associated signaling variant of ISDN, it is used with T1 lines but does not use a D-channel or Backup channel. Use NFAS None when the T1 is part of an NFAS group but the T1 does not contain either a primary or backup D-channel.	24