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are becoming more and more crucial. Simply
picking random IT hardware doesn’t work if
you have to deal with real-time processing of
high-bit-rate signals such as in uncompressed
video over IP.
S3: Hardware monitors, as opposed to
software probes, have two great advantages:
(a) they have the unique ability to assess the
quality of service delivery across a video
platform with a cast-iron guarantee that they
are not in any way modifying the systemunder-test; and (b) when they incorporate
the use of real customer CPE as part of the
hardware monitor, they are the closest
possible representation of the real customer
experience being delivered by the video
platform at all points in the headend and
network where they are deployed. On the
other hand, software-only monitoring has the
benefit of being easier to deploy in many
cases. Ultimately, we believe that a blend of
both hardware-based and software-based test
and monitoring are required to span the
entire content delivery chain.
Tektronix: One area where hardware-based
measurement is essential is for RF
measurement. Although it may be supposed
that software defined radio (SDR) could
replace some aspects of the hardware, in
practice, the complexity of demodulation
combined with the scale necessary to
monitor multiple RF signals simultaneously,
preclude its cost-effective use at this time.
Many compressed video and audio quality
monitoring devices are becoming
increasingly software-based, although it is
common to supply them as appliances rather
than as standalone software.
Torque: Simple. Any time you need a direct
and physical connection to 'the signal'.
Monitoring is all about checking the signal as
it moves from A to B. If that's done with a
coax cable, there is no choice but to connect
a tap and monitor there. In a headend, there
are usually two main concerns: a) Is the
inbound signal coming in? (and properly?);
and b) Is my outbound signal going out?
(and properly!). Unless the headend itself is
in the cloud, monitoring input and output of
live signals can only be done with physical
monitors on-site at the facility. If t