Everything You Wanted To Know About Cable Technology5/28/2010 3:59 PM Eastern
It happens to all of us. You’re in a meeting.
Engineers are present. You veer off mentally — just for
a second! — and by the time you’re back, the conversation
thickened into uncomfortably unfamiliar technical
Acronyms, nested acronyms, spoken acronyms. Wideband,
IP, QAMs. Cable tech jargon has a beginning (the late
1940s), but it has no end. For that reason, we’ve put together
this roundup of tech “translatables” — to answer the unasked
questions, and, at the least, to make you a capable
1 Why is everyone talking
about IP video?
Perhaps the strongest undercurrent in cable technology
today is the shift toward “IP video” and “IPTV” — because
it’s considered more efficient and cheaper than
regular cable TV. On the surface, it’s about sending the
full video lineup (linear and on-demand) through the cable
modem, over a home network, to connected devices
including and beyond the TV.
IP touches pretty much every component of video delivery,
from the way it’s sent from originators to the way it’s navigated
by consumers and everything in between: ingest, transport,
headend gear, in-home gear, home networks, software.
The work of it is opening up the interfaces between components
to extend development to Web-based interactions.
But what is IP, exactly? Technically, Internet protocol
is a nickname for a longer protocol, known as TCP/IP, or
Transmission Control Protocol/Internet Protocol. It’s the
underlying language of the Internet, used by data communications
equipment to speak to one another — so that all
of the pieces of the chain know where and how to send information.
The good news is that we don’t have to call it “TCP/IPTV.”
2 Explain “all-IP” versus
At the 2003 National Show, Microsoft’s Bill Gates asked
Comcast CEO Brian Roberts whether and when the cable
industry would go from “all-digital” to “all-IP.”
Since then, the digital transformation occurred — most
cable providers now offer the core lineup of cable networks
in standard and high-definition digital.
Just as there were different ways to send analog signals
— your radio tunes AM and FM frequencies, for instance —
there are different ways to send digital signals. IP is one of
them. “MPEG transport” is the other. (And it came first.)
In the shortest of shorthand, IP transport moves data
through the cable modem side of the house. MPEG transport
moves data through a set-top box.
3 Can cloud computing
In its simplest form, “cloud computing”
means processing and storing stuff in the
network as opposed to at the end points,
like your TV or your set-top box.
Cable could definitely benefit from this
category, particularly with navigation across
multiple screens. One screen (the TV) may be
outfitted for MPEG-2 decompression, while a
newer screen (handheld) may use MPEG-4.
Likewise for screen resolution — each
screen needs a specific amount and type of
code. But should that processing be done
within each end device or higher up in the
Cable operators could also offer more services
The cable industry is already an interconnected
system of local, regional and national
networks; in other words, it already is a
between EBIF and SelecTV?
SelecTV is to EBIF as Tru2way is to OCAP:
the public marquee for a group of technical
Just as “Tru2way” became the retail front for the still-active technical
specs known as “OCAP” (OpenCable Applications Platform),
“SelecTV” will become the icon that visually indicates an interactive
event to TV viewers.
Refresher: EBIF stands for Enhanced TV Binary Interchange Format
(see Special Report). It’s a way to get a clickable thing onto a
very wide footprint of cable-connected screens.
What’s big about EBIF is its reach — as many as 30 million homes
this year. Its reach is wide because it’s small enough to run on set-tops
deployed a decade or more ago.
Watch for EBIF to show up in force later this year, for advertising (click
for more info), participatory TV (click a contestant gone) and things like
Comcast’s “ready remind record” feature, for keeping people linked with
the programming they like, even if they forgot to set the DVR.
5 What on earth
is a QAM?
What’s part hardware, part signal, part unit of measurement? QAM.
People tend to say it as a word — kwahm. It stands for “Quadrature
Amplitude Modulation.” Unless you’re wired to listen for it in three
ways, QAM is the king of cable jargon.
In one sense, QAMs are physical hardware, shaped in the “pizza
box” style of rack-mounted gear. A solid vendor community exists to build
video QAMs and data/voice QAMs. Gear-related QAM discussions these
days usually center on density — how many can fit in one pizza box? Comcast’s
new “CMAP” initiative aims for 160.
QAM is part method because it exists to imprint (modulate) digital information
onto a communications carrier for conveyance to the items at
the end of the plant: set-tops, cable modems, voice terminals.
And QAM is partly a unit of measurement, in that its current carrying
capacity is 38.8 Megabits per second. (People often round this up to
40 Mbps). Example sentence: “We’re using four QAMs for IPTV.” That
means dedicating four 6-MHz channels, each with a carrying capacity
of 38.8 Mbps, to make one big, 155-Mbps IPTV passageway.
There’s just no escaping QAMs. Best to learn to listen for it three ways.
6 Will CDNs ever
replace satellite TV?
As IP infiltrates the world of networks, so does traditional satellite
receiving technology get augmented with fiber backbones, loosely
known as Content Delivery Networks, or CDNs.
Remember the telecom bust a few years back? In its wake was a glut
of dark fiber, strung but not lit up with traffic.
Sending data over those local, regional and national fiber rings, all interconnected,
is less expensive than sending it up into space, then back
down again. That’s why CDNs are gaining so much attention these days.
7 Will cable operators ever
offer smart phones?
They already are! Rogers Communications in Canada offers a full line of
smart phones, and U.S. operators are expected to get in on the game.
In the language of “smart phones,” walled gardens are what’s dumb.
Remember when carrier-provided “walled gardens” were the only way
to get new applications for your cellular phone? Smart phones come
with Internet protocol (IP, there it is again!) connections for zipping
off to the Internet, or an open-source apps store, for whatever you desire
for your mobile gadget.
Cable companies, which are notorious for wanting more control of
the network, will find that the open-source nature of the smart phone
is a selling point, not a competitive downside.
8 What’s up with
You’ve heard about DOCSIS 3.0 for a while now — it’s the latest
metamorphosis of the technical specification for the cable modem.
And you know that “channel bonding” is the big feature, and
that cable operators are up to their eyebrows in deployments. Why
do you continue to hear it peppered in every other conversation?
Because it’s those bonded, 6-MHz channels — those bonded
“QAMs” — that become the transit lane for IP video. Back-of-the-envelope calculations from cable’s engine rooms indicate a need
for between six and eight 6-MHz channels, bonded, to carry an
exact replica (in IP) of what’s already available in linear and ondemand
9 What’s ‘TV Everywhere’/
Part of the business of getting subscription TV on screens other than
the TV is making sure Customer Jane Doe really is Customer Jane
Doe — and not her 50 friends, outfitted with her log-in credentials.
That’s why cable operators and programmers are working, individually
and together (in an underground tech effort known as the Open
Authentication Technology Committee), to make sure consumers can
get to the content they’re paying for. Easily, and without a lot of hassle,
on the TV, PC or handheld.
Ultimately, the intent is for subscribers to be able to go to an aggregated
video site (e.g. Fancast/Xfinity) or to individual program
network sites, log in — once — and view the content associated with
And even if Customer Jane closes her browser, goes to lunch, comes
back and opens another content owner’s site, she’s still logged in. Much
less of a hassle for her. That’s the plan.
10 What’s a selectable
“Selectable output control” is regulatory-speak for giving movie
studios permission to select the set-top output that keeps their
titles the safest (from piracy).
This one dates back eight years. Remember the Memorandum of Understanding,
submitted by cable and the consumer-electronics industry,
which ultimately begat the one-way plug-and-play agreement?
Short version: Cable sided with CE, saying that it wouldn’t disable
the analog outputs on its set-tops. Reason: CE didn’t want their sets to
go blank, for any reason. Ever.
But studios were (and are) concerned about what’s known as “the
analog hole” — the ability for a premium title to flow over an unprotected
(component video or other analog) connector to a screen or
The fear: Titles get compromised at infancy. With a predictable effect
Selectable output control, often abbreviated “SOC,” re-entered the
day-and-date mainstream on May 7, when the FCC approved its use.
Despite its wonky name, this is a big one because studios are now comfortable
offering cable day-and-date showings of new movies, in near the
same window as theatrical — think how hot this is for VOD!