How do you watch television? Nearly 70% of us get our TV via
one of the major cable providers. Satellite has carved out a good
niche and grabs more than 20% of that market. If it’s strictly
over the air, then hold your hand up as one of the 15% who still
claim that as their means of reception. (That will change, as
analog TV transmission expires on February 17, 2009.)
Now the dawn of Internet Protocol TV (IPTV) is changing
the landscape even further. AT&T, Verizon, and other
telecommunications (phone) companies (telcos) are making a
huge effort to bring TV to the Internet and over fiber. There
are some tremendous benefits to IPTV. However, some interesting
technical and business challenges must be dealt with,
not to mention the fact that cable is fighting back.
“What if any new benefits does IPTV bring over cable?”
asks Peter Percosan, Texas Instruments’ director of broadband
strategy. The IPTV services are essentially at parity with the
cable companies even though their content offerings are still
a bit below what the premier cable companies offer. The main
difference is the pricing advantage that IPTV has over cable.
It remains to be seen how long that lasts, though, even as
content grows. The telcos need some clear, distinguishing
factor to help them gain a stronger foothold in the pay-TV
business. According to Mike Coward, CTO of Continuous
Computing, two benefits could make the difference.
First, in IPTV, each subscriber gets a different video/audio
stream that’s specifically just what that subscriber has selected
with the remote control. All of the content is sent via fiber to
the neighborhood DSLAMs (digital subscriber line access
multiplexers). At this point, the customer’s selected channel is
picked out and sent to the set-top box (STB). Cable customers
always get all of the content selected by the STB consumer.
Thus, telcos have the opportunity to do targeted marketing
and advertising, which isn’t possible with cable.
Second, IPTV subscribers can select time-shifted TV
watching. This is done now with a TiVo box or digital video
recorder (DVR) at the subscriber’s home. Telcos can offer what
might be called network personal video recorders (PVRs),
where the stored video is on the carrier’s servers (for an extra
charge). These options may be the
differentiator the telcos need to
succeed with TV.
IPTV EXPLAINED
The term IPTV should explain
itself, but the definitions are tricky.
IP means the Internet Protocol, of
course, so it implies the transmission
of video and audio using the
IP. However, that’s not the same
as Internet TV, which is what we
call those YouTube videos and clips
using Microsoft wave files. And it’s
not the video supplied by Google,
Yahoo, MySpace, or Microsoft that
viewers watch on their PCs.
Figure 1 shows the basic structure
of an IPTV network. The telecom
network is fiber to the neighborhood
and a fast DSL line to the
customer’s home for Internet access
on the PC or IPTV. This diagram
shows that IPTV also could
be delivered over a cable network
and could very well occur in the future. A hybrid STB that
can accommodate IPTV,
cable, or even digital broadcast
over-the-air TV may be a
necessity in some areas.
There are two good examples of IPTV
in the U.S. AT&T’s U-verse system,
which began in Texas, is now rolling out
across the country in selected areas. Fiber
is run to the neighborhoods and terminates at a DSLAM that
gives access to AT&T’s phone customers via the installed copper
unshielded twisted pair (UTP) base. Using fast ADSL2 or
VDSL2, the TV then is delivered to the customer’s TV set in
compressed format.
Because it’s a fast broadband Internet connection, the customer
can also get DSL Internet access service up to 6 Mbits. (Voice
over IP, or VoIP, is optional.) These bundled “triple-play” services
are a bargain compared to what you pay for the individual services
and in most cases less expensive than equivalent deals from
the cable companies.
The other example is Verizon’s FiOS. This full-blown fiber-tothe-
home (FTTH) service offers TV, high-speed Internet service,
and VoIP. Downstream speed is 50 Mbits/s and upstream is 20
Mbits/s, the fastest available to date. FiOS isn’t true IPTV, since it
uses a delivery method similar to cable TV’s modulated RF system
for TV, data, and other services. But rumors abound that Verizon
will change to an all-IPTV system in the future.
While fiber is expensive, it’s the ultimate answer to higherbandwidth
broadband services. DSL providers of Internet service
have already hit the wall, so to speak, with data rates usually maxing
out at 6 Mbits/s (slightly more in a few places). High-end
DSL versions like VDSL2 do provide very high rates, but only
over short distances.
Some carriers have tried using VSLS2
on two UTPs in the cable reaching 50
Mbits/s over longer distances. Top cable
rates for ordinary service are faster, but
cable companies have nearly hit the limit
at about 20 Mbits/s with current systems
and prices are high.
Thanks to the new cable protocol DOCSIS
3.0 (Data Over Cable Service Interface
Specification), cable can now offer rates to
about 50 Mbits/s with a technique called
channel bonding. Fiber is the only way up
beyond this point. So while it is expensive,
you will begin to see more and more
fiber in the future. TV demands it and consumers
are pressing for faster downloads,
uploads, and gaming capability. IPTV can
provide that, but cable is clearly keeping up
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