Features And Functions - Nortel Enterprise 1000 Reference Manual

Page 182 of 236

Features and functions

553-3023-211 Standard 1.00 June 2001
NTAK93 D-channel handler interface daughterboard
trunk card is installed in the Succession CSE 1000 Media Gateway. Digital
trunk cards are not supported in Media Gateway Expansions.
The NTAK93 provides the D-channel handler interfaces required by the
ISDN PRI trunk.
The DCHI performs D-channel Layer 2 message processing and transfers
Layer 3 signaling information is mounted on the NTAK09 1.5 Mb DTI/PRI
card or the NTBK50 2.0 Mb PRI card (installed in the Media Gateway) using
standoff reference pins and connectors. The NTAK93 daughterboard, when
mounted on the NTBK50 PRI digital trunk card, is addressed in the same slot
as the NTBK50. The NTAK93 daughterboard can use SDI I/O addresses 1 to
15 and port 1.
The NTAK93 daughterboard provides the following features and functions:
• D-channel interface (DPNSS interface is not supported at this time)
• special features included for LAPD implementation at DCH:
— system parameters are service changeable (system parameters are
downloaded from software)
— incoming Layer 3 message validation procedures are implemented
in the D-PORT firmware
— supported message units and information elements can be service
changed
— translation of the CCITT message types information elements into a
proprietary coding scheme for faster CPU operation
— convention of IA5-encoded digits to BCD-encoded digits for
incoming layer 3 messages for faster CPU operation
— self-test
— loopback