IP: re: HDTV, spectrum allocation, etc.

[David Farber <farber () cis upenn edu>]

To: farber () cis upenn edu
From: "Willis H. Ware" <willis () conrad rand org>


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Folder: YES
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Dave:


But there are many other considerations than as mentioned by Dennis
Allison; in particular, continuity of service.


Having lived with a local cable service here for over 10 years, it has
become obvious that the cable is off the air much more often than are
traditional TV broadcasters and for a longer time during an outage.  There
are probably many reasons; e.g., the broadcasters have one central facility
that can be protected against damage and be supported with locally
generated power, the broadcasters have much longer experience with
self-protection, the cable is really a distributed system depending on
localized power sources and land-line cabling, the inherent vulnerability of
cable networks to all manner of physical damage.  Among the events that
have taken out the local system: a garage fire whose flames burned through
the cable, a vehicular accident that knocked over a pole and severed the
cable, area brownouts or power interruptions that take cable amplifiers off
the air, just plain failures of cable amps, squirrels eating through the
cable insulation.


Perhaps continuity of service is of lesser importance in the entertainment
context; but at least here in Southern California, the commercial TV network
is an important channel of information for emergencies.  During the major
earthquake a couple of years ago, the broadcasters were back on the air long
before the cable came back. I was watching TV as soon as my residential
power returned (and it was off only two hours) -- but it was on rabbit ears,
not the a cable source.  I never checked into details, but I'd guess that
the broadcasters were probably off the air for a very brief time.


And I can't see cable systems being of much value in a tornado- or
hurricane-ravaged area.


If the country is going to maintain a viable and sustainable emergency
communications capability to keep the public informed in case of regional or
national disasters (include: terrorist consequences), then let's be cautious
before we summarily dump commercial broadcasters in favor of cable.  Let's
look at all the angles.


And before somebody observes that satellites (e.g., DSS) could be
dependable, remember that I can buy battery operated TV sets, but I cannot
buy battery operated DSS receivers.  And I might have to get on the roof of
a quake or fire damaged structure to realign a dish antenna; or I might not
even have a structure on which the dish has been located.  And there would
be some question as to how regional emergency announcements and information
would find its way onto the DSS channels.


In the case of the Simpson trial #2, I know how MSNBC worked. From the
local interviewing tent across the street from my office, the traffic went
by satellite hop to MSNBC's programming center in northern New Jersey, then
via another sat-hop to the MSNBC ground station somewhere in Colorado, and
finally up to the bird.  The local interviewer who was listening to the DSS
broadcast experienced a several second delay between what he said and what
he heard.  The technician told me that much of this was due to the delay
inherent in the MPEG-2 coders, plus all the round-trips to synchronous
alitutde.


The question of how to provide TV services to the public is much more
complex than as suggested by Dave Allison's commentary.  While the points
that I have raised could be probably countered with a thoughtful
system-level design -- and traditional radio broadcast would naturally be
factored in, it would take government intervention (probably) to make an
adequate national arrangement happen, as opposed to the really quite
resilient present arrangement that has evolved nationally, all driven by
commercial motivations, history, technology, and good old capitalism.


                                        Willis Ware
                                        RAND
                                        Santa Monica, CA


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