coverstory2_cover story 28/11/2013 16:55 Page 4
operator organisation.
Bridge: For hybrid services to reach their
potential, they have to offer a coherent
experience. But below the surface, the hybrid
is an amalgam of radically different
technologies. You can’t compare the RF level
in a terrestrial signal and the chunk size in
the IP stream. They may both be digital but
they have nothing in common otherwise, and
for hybrid services you need to have
provision for monitoring both sets of
technologies, within a monitoring
environment that provides seamless
correlation. Providers
need to understand that
there are two parallel
technologies to monitor
and this increases the
monitoring requirement.
Without a fully comprehensive approach,
providers can’t expect to deliver a coherent
service.
DTVL: To ensure a great user experience,
the broadcaster’s app needs to work well on
the user’s TV device and if the app delivers
video it needs to start quickly, with minimal
buffering and be as high quality as possible.
For service providers operating in a
horizontal retail market, delivering a quality
app to a huge range of devices is challenging
and reliant on open standards. Regarding
delivery of video content over IP, the use of
adaptive bitrate technologies, particularly
MPEG-DASH, by both broadcasters and payTV operators is seen as the most costeffective and future-proof solution. Using
MPEG-DASH avoids vendor lock-in and
provides a standardised transition path to
deployment of HEVC. Edgeware: Service
providers are looking to deploy a single CDN
capable of delivery across multiple access
networks e.g. HFC to DVB-C tuners and IP to
Ethernet ports on the HbbTV STBs. Next-gen
CDN servers need to deliver both protocols
required and to monitor the delivery with a
consolidated analytics system. Today, most
CDNs only deliver over IP and completely
separate delivery servers are needed for
delivery over the cable QAM. The monitoring
devices. Then a provider can build up a
pattern which, if there are problems with the
service, allows the engineers to hone in on
where the issues are arising. Understanding
how viewers connect is important, whether
WiFi or PLC. Providers need to understand
the capabilities and limitations of their
subscribers’ access points and client devices.
JDSU: One of the immediate challenges is
that QoE/QoS is inherently different for
broadcast and online viewing experiences.
The metrics are different and the criteria are
different. When you merge the live TV and a
streaming online service, you effectively
merge the QoS/QoE test burden.
Synchronisation and format compatibility
becomes a concern as well.
Mariner: This actually is not as big of a
problem for service providers as might be
expected—thanks in no small part to the
increased use of software in the process.
While HbbTV and similar hybrid services do
bring multiple content streams to the same
end devices, one platform can be used to
monitor multiple experiences across the
same data stream and effectively provide upto-the-minute data on potential problems or
complications before they reach levels that
impact the end user experience.
Nexidia: As the number of distribution
channels increases so does file movement
and transcode operations. This greatly
increases the risk for error and thus greatly
increases the need for trustworthy automated
QC.
S3: Some of the key performance indicators
(KPIs) for QoE can be equally challenging to
manage on each type of delivery platform,
albeit for different reasons. One good
example is Fast Channel Change, where
clearly a smaller FCC time is better from an
end consumer’s perspective. On broadcast
networks, the time to tune from one channel
“All broadcasters and providers acknowledge there
are challenges in offering services in an unmanaged
network environment.”
systems are completely separate for both
networks.
Farncombe: All broadcasters and providers
acknowledge there are challenges in offering
services in an unmanaged network
environment. However, it is still desirable to
monitor at the points in the delivery service
where it is possible – including end client
18 EUROMEDIA
to the next may involve a combination of
tuner acquisition, transport stream filtering
and navigation, elementary stream
processing and video and audio decoding as
critical steps in the process. In a hybrid
network that has both types of distribution,
diagnosing and solving problems to achieve a
particular FCC KPI will require a wider
variety of tools and expertise than has been
the case previously.
SeaWell Networks: Typically, multiscreen
content flowing over a network is likely to be
delivered by a cache based network. This
removes the ‘per session’ ability to impose
specific QoS or QoE parameters, unless
supported by the last point of delivery. This
is leading to a requirement for an intelligent
layer that provides an integrated set of
interfaces for not only policy management,
but also ad insertion, blackout, nDVR and
any other service that requires per session
delivery. Incidentally, if
dynamic repackaging is
also implemented at the
edge of the network this
has the added benefit of
dramatically reducing
the cost of edge storage and optimising the
origin, mid tier and edge cache by up to 70%,
while further optimising the cache
utilisation.
Tektronix: The act of viewing a channel
that happens to be streamed should not lead
to experiencing extremely low media quality
nor should it lead to an asset that fails to
playout part way through. This is one of the
key reasons why we at Tektronix heavily
stress the importance of checking all
streamed assets at the content preparation
stage for QoE and also monitoring the QoS of
the content delivery platform.
Triveni: What makes the hybrid situation
especially difficult is the need for some level
of synchronisation between the two — in
addition to an understanding of what the
hybrid applications are actually doing — in
order to measure any quality metric.
Witbe: IPTV started the video over IP
revolution. It was quite complex to scale, so
the test and monitoring industry focused on
developing solutions to control streams. At
that time, we thought that the challenge was
rather to test and monitor the interactive
applications IPTV enabled. Now, with
HbbTV, everybody is realising that
monitoring user interactions is critical.
Wohler: The main challenge in ensuring
QoS and QoE over both broadcast and online
platforms rests in monitoring all of the key
elements — the pictures, PID tables, audio
levels, safe areas, etc. — effectively and
efficiently. While most current solutions
require multiple pieces, such as a decoder,
monitor, and audio meter, our MPEG Series
packages all of that functionality within one
box that allows users to view the HD-SDI
origination output, the outgoing ASI signal,
the ASI feedback loop, and the IPTV feed
side by side, along with essential data and
access to PID tables and diagnostic tools if