Nortel Networks Circuit Card - Manual (Page 199)

NT5D11 and NT5D14 Lineside T1 Interface cards Page 199 of 906
Circuit Card Description and Installation
The lineside T1 card is an IPE line card that provides a cost-effective
all-digital connection between T1 compatible terminal equipment (such as
voice mail systems, voice response units, and trading turrets) and the system.
The terminal equipment is assured access to analog (500/2500-type)
telephone type line functionality such as hook flash, SPRE codes and
ringback tones generated from the switch. Usually, the lineside T1 card
eliminates the need for channel bank type equipment normally placed
between the switch and the terminal equipment. This provides a more robust
and reliable end-to-end connection. The lineside T1 card supports line
supervision features such as loop and ground start protocols. It can also be
used in an off-premise arrangement where analog (500/2500-type) telephones
are extended over T1 with the use of channel bank equipment.
The lineside T1 interface offers significant improvement over the previous
alternatives. For example, if a digital trunk connection were used, such as
with the DTI/PRI interface card, lineside functionality would not be
supported. Previously, the only way to achieve the lineside functionality was
to use analog ports and channel bank equipment. No channel bank equipment
is required, resulting in a more robust and reliable connection.
The lineside T1 interface offers a number of benefits when used to connect to
third-party applications equipment:
• It is a more cost-effective alternative for connection because it eliminates
the need for expensive channel bank equipment.
• The lineside T1 supports powerful T1 monitoring and diagnostic
capability.
• Overall costs for customer applications can also be reduced because the
T1-compatible IPE is often more attractively priced than the analog-port
alternatives.
The lineside T1 card is compatible with all IPE based systems and standard
public or private DSX-1 type carrier facilities. Using A/B robbed bit
signaling, it supports D4 or ESF channel framing formats as well as AMI or
B8ZS coding. Because it uses standard PCM in standard T1 timeslots,
existing T1 test equipment remains compatible for diagnostic and fault
isolation purposes.