Multiscreen & OTT 2012 > Technology
Digital TV Europe
July 2012
Network service providers and the CDN
Quality assurance
Operators and content owners delivering to
multiple screens must absorb costs both fixed
and variable. While headends are fixed costs,
Content Delivery Network (CDN) costs vary with
the number of viewers a video asset attracts.
While the headend is the biggest item of capital
expenditure, CDN costs therefore can make the
real difference over the long term. CDN costs
will multiply if video service providers need to
deliver multiple copies of the same asset many
times. “The headend is the biggest capex initial-
ly but CDN is what makes the difference in the
long term,” says Boris Felts, vice-president,
product marketing, Envivio.
Live content presents a particular set of chal-
lenges. Video processing providers can convert
video on the fly for distribution downstream.
“From one encoder you can receive one chan-
nel and create multiple renditions. You might
have 10 resolutions from small screen to HD,”
says Felts. “Out of these 10 resolutions you
need to have two or three ways to package it –
over MPEG Transport Stream, in Adobe Flash, in
3GPP, in HTTP Live Streaming – so we can pro-
vide 40 variants of the same live channel com-
ing in,” says Felts. As many flavours of video
assets also need to be created for catch-up pro-
gramming and video-on-demand.
In order to simplify and save bandwidth,
operators have turned to the concept of the
mezzanine format, where multiple resolutions
are created in a package from which different
flavours can be created to support the different
format as required at the edge of the network.
Services including network DVR and personali-
sation of advertising is best done at the edge.
Delivering content efficiently to multiple
devices has led operators to turn to CDN
providers and has opened up the possibility that
they may be able to market their own ‘access
network CDN’ infrastructure to third-party con-
tent providers. Few network operators have
tried to take on the Akamais of the world direct-
ly and there has been relatively little movement
towards the development of a significant access
network CDN business so far, however.
“We believe network service providers will
try to leverage what others can’t,” says Jacques
Le Mancq, CEO of Broadpeak, a specialist in
access network CDN. This could mean trying to
use the home network as a tool within the CDN:
“We believe that the home gateway and to a
lesser extent the set-top can play a role in con-
tent distribution and be part of the CDN, either
as a cache or to deliver live content.”
Service providers can also use their networks
to deliver so-called on-the-go access outside
the home, for instance by partitioning in-home
equipment to deliver wireless hotspots, says Le
Mancq. Operators face the issue of how to
makemoney from this – either by marketing
CDN services to content providers or by selling
its own subscription services. In the latter case,
they may wish to grant privileged access to
their services on the assumption that con-
many streaming formats,” he says. “We might
be lucky sometime in the future, and might
end up with truly consolidated industry where
a single VOD file format and a single stream-
ing format will be all that it is needed to reach
100% audiences. However this dream is for
the distant future.”
The need to prioritise the more popular
devices nothwithstanding, Nativ’s Folland
argues that the relentless pace of innovation in
consumer electronics means that broadcast-
ers really can’t afford to pick and choose. In
addition to improvements in the processing
power of devices enhancing their ability to
play back high quality video, there are also
ongoing improvements in the user experience
driven by social networks and software
providers that means broadcasters need to
have access to rich metadata. “At the moment
it’s a great big mess – it’s an exciting mess but
people need to understand the challenges for
content owners,” says Folland.
Given the heterogeneity of the environment in
which those content owners are now expected
to operate, one of those challenges is measur-
ing and monitoring the consumer experience
and gathering data on consumer expectations
and how users are behaving.
According to Johan Görsjö, strategic prod-
uct manager at quality assurance specialist
Agama Technologies, extending quality assur-
ance solutions to the OTT environment is not
particularly problematic, with software
embedded in the player via which the video is
consumed rather than on the set-top box.
Multiscreen means a more complex delivery
chain, however, says Görsjö. “You have more
devices in the home and a more complex
delivery chain with more entities involved,” he
says. “Having a monitoring system that can tie
all the parts together is an important benefit
for the operator, because TV everywhere is
more complex than cable.”
TV Everywhere services could involve video
being handled by multiple CDN providers
that do not provide comparable data sets,
meaning that it is difficult to see how the cus-
tomer experience is affected, he says (see side-
bar for more on CDNs). Only one part – the
service provider – is going to be held respon-
sible by the customer for anything that goes
wrong, on the other hand. “Many CDNs offer
information but you may not be able to com-
pare it and decide what it means for the cus-
tomer experience. It’s going to be a challenge
for operators and something we want to pro-
vide to give them and idea of what it all means
for service quality,” says Görsjö. Embedding
monitoring software in the player at the point
of consumption can enable information to be
provided to the service provider without the
need to invest in expensive hardware, he says.
Görsjö also points out that adaptive bit-rate
encoding, which also adds complexity to mon-
itoring services, should not be seen as a silver
bullet by service providers. “You could give
customers inconsistent quality because bit-
rates keep toggling between bit-rates or cus-
tomers keep getting driven down to the lowest
bit-rate – you don’t want Game of Thrones
pushed down so it looks like a YouTube clip,”
he says.
Agama’s CEO Mikael Dahlgren says that
operators typically are not looking to target
every Android device in the market. “It’s not
Le Mancq: the home
gateway and set-top
box can be part of the
CDN infrastructure.
sumers of free services do not necessarily
expect high quality and availability of the serv-
ice. But the danger of this strategy is that con-
sumers may simply blame their internet service
provider for poor video quality on services they
want to consume.
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