Field-Programmable Gate Array (Fpga) Testing; Outgoing Calls Attempted/Completed Mismatch - Nortel 1000 Description, Installation And Operation Manual

Field-Programmable Gate Array (FPGA) testing

Outgoing calls attempted/completed mismatch

Before communicating with the system, the 8051XA controller downloads
FPGA data files and performs tests to check correct programming of the
FPGA.
The difference between the attempted and completed outgoing call numbers
should never be less than the sum of the QoS Fallback, Address Translation
fallback, and Calls Rejected fallback (totaled as "Outgoing Fallback"). It may
be more. A caller may release a call before the attempt reaches the far node,
but since the originator released before the call could complete, it might not
even be recorded as an attempt by the remote ITG card.
For example, a user dials a valid ESN AC1 and LOC, but an incorrect DN
(with an incorrect last digit). As soon as the user dials the digit, he or she
realizes the mistake and releases the call. The SETUP message has already
gone to the ITG card, but the call is cleared before the H.323 SETUP message
traversed the IP network, so no call reaches the destination. An outgoing
attempt has been made and cleared, so no fallback occurred and no call
attempt is recorded at the destination.
The main reasons for valid completed call mismatches are:
• Time of day that the statistics were last read and cleared may vary.
This is the most common reason for mismatch. For example, although
both ITG cards were read at 10:00, it is important to know if the clocks
are synchronized, and when statistics were last cleared. A one-minute
discrepancy could mean quite a few calls in the difference. Therefore, the
first eight calls of one card may have already been counted for the other
card. The statistics are more reliable when looked at over the day.
• "Messages in flight"
This ranges from trivial to extreme. In the extreme case, if a CONNECT
message is delayed several tenths of seconds (or even seconds) by traffic
bursts, the snapshot may occur while the CONNECT message is still
traversing the network. Therefore, one or more calls is still unaccounted
Maintenance
IP Trunk Description, Installation, and Operation
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