Functional description 963
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 two B-channels and one D-channel the
MISP supports 64 B-channels and 32 D-channels. If the MISP is carrying
packet data, it must dedicate one of its D-channels to communicate with the
external packet handler. In this case the MISP supports only 31 DSLs.
The main functions of the MISP are:
•to communicate with the CPU to report ISDN BRI status and receive
downloaded application software and configuration parameters
•to manage data link layer and network layersignaling that controls call
connection and terminal identification
•to control terminal initialization and addressing
•to assign B-channels for switched voice and data transmission by
communicating with the BRI terminal over the D-channel and allocating
to it an idle B-channel with appropriate bearer capabilities
•to separate D-channel data from signaling information and route the
data to the packet handler
•to send call control messages to ISDN BRI terminals over the D-channel
The MISP supports the downloading of ISDN applications from the Option
11C software daughterboard. The MISP is downloaded with the appropriate
application code:
•on the first enabling of the MISP card
•when Option 11C 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. The next time the system or MISP
card resets, the application is loaded from the MISP Flash ROM provided
there are no new or differentapplications on the software cartr idge.
The NTBK22 MISP Card interfaces with the S/T Interface Line Cards
(SILCs) and the U Interface Line Cards (UILCs). The main functions of the
MISP are as follows:
•communicate with the Call Server CPU to report ISDN BRI status and
receive downloaded application software and configuration parameters
•manage Layer 2 and Layer3 signaling that controls call connection
and terminal identification
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23May 2008
Copyright© 2003-2008, Nor tel Networks
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