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Page 520 of 544 NTBK51 Downloadable D-channel handler
553-3011-100 Standard 14.00 January 2002
Overview
The NTBK51 provides Downloadable D-channel handler (DDCH) interfaces
based on the Multipurpose Serial Data Link (MSDL). The DDCH provides a
single purpose full-duplex serial port capable of downloading the D-channel
application and base software into the card.
Features and functions
The NTBK51 provides the following features and functions:
• ISDN D-channel related protocol
• Selftest
• Loopback
• D-channel loadware including:
— management and maintenance
— LAPD- software for data link layer processing
— Meridian 1 DCH interface
— layer 3 preprocessor
— traffic reporting including link capacity
Physical description
The Downloadable D-channel (NTBK51) is a daughterboard that mounts on
either the NTAK09 1.5 DTI/PRI or the NTBK50 2 Mb PRI card. The DDCH,
in conjunction with the NTAK09/NTBK50 circuit card, can reside in any
physical slot 1-9 of the main cabinet and 11-19, 21-29, 31-39, or 41-49 of an
IP Expansion cabinet.