CHAPTER 6: REMOTE DEVICE ALERTS
6-10
MDU Solutions
®
– UCrypt
®
Monitoring Server - Operation Manual
rate then falls below 38.8 Mb/s the alert will be sent next time that the bit rate again exceeds 38.8 Mb/s.
6 .13 .3 Customer Symptoms
Customer experiences flickering, artifacts and/or other impairments on all programs on the affected multiplex for the duration
that the error condition exists with the degree of impairments escalating with the severity of the condition. The resulting effects
will be both random and variable depending on the conditions causing the error and it is not possible to quantify them further.
6 .13 .4 Urgency
Medium.
6 .13 .5 Cases Where Alert is Likely a Result of:
Outside influence or normal operation
If this alert is received repeatedly, it indicates that the variable bit rate nature of the programs assigned to a QAM are peaking
above 38.8 Mb/s under some content conditions and a brief outage or picture breakup is occurring on all programs on
that QAM at the time of the peak rate. The programs on the affected QAM must be spread out over more QAMs. The total
aggregate bit rate on the affected QAM must be reduced.
An Internal Issue
Read the paragraph above as this is the most likely cause. If it is absolutely clear that the multiplex specified in the alert is not
being oversubscribed (i.e. it only has a single program assigned to the output MPTS or has 2 HD’s that the operator knows for
sure are not exceeding 38.8 Mb/s) then the error is likely indicating a temporary failure by the multiplexer to properly process
all packets as it should. This is a rare but possible internal UCrypt cause.
6 .13 .6 Probable Causes
1. There are too many programs assigned to the affected QAM and the aggregate bit rate of the programs exceeds
38.8 Mb/s occasionally or frequently.
2. Internal UCrypt multiplexer error.
6 .13 .7 Next Steps
1. Analyze the number of programs and the maximum possible aggregate bite rate of those programs that are assigned
to the specific troubled QAM and attempt to calculate if only a single program or more are required to be removed
from this multiplex then start removing programs until this alert no longer occurs.
2. Analyze the log for the consistency of the alert over time. It is possible that a single error may occur and may not
necessarily indicate a serious problem requiring attention.
3. It is possible for this error to be an indication of an internal software failing. First eliminate the possibility of too many
programs in the QAM.
4. If an immediate resolution to the issue is necessary, a reboot of the UCrypt should be attempted.
6 .14 UCrypt Output QAM Lost Bitrate Error
6 .14 .1 Refers to
QAM Modulator stops modulating at 38 .8 Mb/s .
The bit stream from the internal multiplexer to the QAM modulator has
failed. This error indicates that the modulator has failed to acquire the bit stream properly.
6 .14 .2 Repetition of Alert
This alert is sent each time it is detected that a QAM has stopped modulating the 38.8 Mb/s stream. If the stream again starts
modulating and fails again, the alert is sent again.
6 .14 .3 Customer Symptoms
Customer experiences loss of all programs on the affected QAM for the duration that the error condition exists.
6 .14 .4 Urgency
Low - High.
6 .14 .5 Cases where Alert is likely a result of:
Outside influence or normal operation
If only a rare occurrence of an output QAM losing bit rate is reported, this could happen due to programs losing bit rate during