Definitions
2-9
Intelligent Peripheral Equipment (.IPE) card slot

assigning

Card slot

priority
Input messages from card slots 1 and 0 in each IPE module (card slot 0 in
each EPE shelf) are directed to a high priority input buffer.. The input
messages from the remaining slots on each -lPE module are directed to a
low
priority input buffer. The system processes the low priority input buffer
only when the high priority buffer and the SL-1 and 500 output buffers are
empty, thereby minimizing input buffer delay on signals from devices in
high priority card slots. This mechanism is important for certain types of
trunks that require critical timing. It is relatively unimportant for other
devices.

Class of service priority

Class of service priority is completely unrelated to card slot priority.
Selected sets and trunks can be assigned a high priority (HPR) class of
service Requests for dial tone from high priority sets and trunks are
processed before sets and trunks assigned a low priority (LPR) class of
service The fewer the sets and trunks assigned as high priority, the better
the service received during heavy load conditions.

Trunks

Incoming Delay Dial, Wink Start, and similar trunks have a timing
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advantage at seizure time when assigned to card slots 1 and 0 in the IPE
module. TIE/DID trunks with DTMF pulsing (incoming) used on the high
priority card slots (1 and 0) have a better chance of attaching a DTR before
the first digit arrives. Trunks using 10 or 20 pps (incoming) should not be
assigned to high priority slots to minimize the number of high priority input
messages during pulsing.
The recommended card slot assignments for trunks is as follows:
-
AIOD type trunks must always be assigned to card slots 1 and 0.
-
Delay Dial, Wink Start and DTMF type trunks should be assigned to a
high priority card slot if possible.
-
Trunks using 10 or 20 pps (incoming) should not be assigned to a high
priority card slot if possible
-
Other types of trunks may be assigned to high priority card slots to
avoid glare, but can also be assigned card slot 2 through 10.
System engineering 553-3001-l 51