Page262 of 544 NTBK22MISP card
553-3011-100 Standard14.00 January 2002
Functional description
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 layer signaling 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
Option11C software daughterboard. The MISP will be 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 ca rtridge 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 ca rd
resets, the application is loaded from the MIS P Flash ROM provid ed there are
no new or different applications on the software cartridge.