Ntbk22 Multi-Purpose Isdn Signaling Processor; (Misp) Card - Nortel Meridian 1 Administration And Maintenance

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Chapter 6 — ISDN BRI trunk implementation
NTBK22 Multi-Purpose ISDN Signaling Processor (MISP) card
The MISP card (NTBK22) is an Option 11 specific card. It performs Data
Link (Layer 2) and Network (Layer 3) processing associated with the OSI
protocol. The MISP is required for MCDN TIE connectivity and for Numeris
and 1TR6 Local exchange connectivity.
Each MISP can support 4 line cards (UILC or SILC or any combination of the
two). Each line card supports 8 DSLs, therefore each MISP supports 32
DSLs. Since each DSL uses 2 B-channels and one D-channel the MISP
supports 32 D-channels.
The MISP supports the downloading of applications from the Option 11
software cartridge. The MISP will be downloaded with the appropriate
application code:
— on the first enable
— when Option 11 Software is upgraded
— when MISP Applications are added/changed.
The applications for the MISP are copied from the software cartridge into
RAM on the MISP card. Only the new/different applications are
downloaded. This information is then copied into the Flash ROM on the
MISP for storage. This process requires approximately 10 minutes to
complete and is carried out while the MISP pack is operational. Next time
the system or MISP card resets, the application(s) is loaded from the MISP
Flash ROM provided there are no new/different applications on the software
cartridge.
Use the equation below to calculate the number of MISPs required to control
SILCs and UILCs.
(SILCs + UILCs) ÷ 4 = MISPs
If the result is a fraction, round it off to the next highest number.
Option 11C ISDN BRI Administration and Maintenance