468 lines
25 KiB
Plaintext
468 lines
25 KiB
Plaintext
|
|
_
|
|
| \
|
|
| \
|
|
| | \
|
|
__ | |\ \ __
|
|
_____________ _/_/ | | \ \ _/_/ _____________
|
|
| ___________ _/_/ | | \ \ _/_/ ___________ |
|
|
| | _/_/_____ | | > > _/_/_____ | |
|
|
| | /________/ | | / / /________/ | |
|
|
| | | | / / | |
|
|
| | | |/ / | |
|
|
| | | | / | |
|
|
| | | / | |
|
|
| | |_/ | |
|
|
| | | |
|
|
| | c o m m u n i c a t i o n s | |
|
|
| |________________________________________________________________| |
|
|
|____________________________________________________________________|
|
|
|
|
...presents... ISDN:
|
|
Fucking the Vacuum Cleaner Attachments
|
|
by Reid Fleming
|
|
|
|
>>> a cDc publication.......1993 <<<
|
|
-cDc- CULT OF THE DEAD COW -cDc-
|
|
____ _ ____ _ ____ _ ____ _ ____
|
|
|____digital_media____digital_culture____digital_media____digital_culture____|
|
|
|
|
A short explanation is in order here. Reid originally wrote this article
|
|
at the behest of the staff of _Mondo 2000_. Once finished, however, certain
|
|
political entanglements developed in the upper echelons of the magazine, and
|
|
Queen Mu, _Mondo_'s Magazine Dominatrix opted instead to hand the writing
|
|
assignment over to the guy she was currently boning (who, rumor has it, can
|
|
barely operate a computer, let alone write about technology). We wonder how
|
|
much research he had to do.
|
|
|
|
As a result, Reid has opted to publish this article through the Bovikazi.
|
|
Hope you enjoy it.
|
|
|
|
-- Omega
|
|
______________________________________________________________________________
|
|
|
|
This article exists thanks to the following people:
|
|
|
|
Brian Valente R.M. Dudley Corporation
|
|
Jamie Agius Pacific Bell
|
|
Aaron Braunstein DataHaus
|
|
Telecommunications Branch California Public Utilities Commission
|
|
Regina LePak PictureTel Corporation
|
|
Igor France Telecom
|
|
My Bovine Brethren cDc
|
|
|
|
|
|
The connection between the net and heaven is explained in
|
|
the following passage taken from the _Tao Te Ching_: "The
|
|
net of heaven... is wide-meshed but lets nothing through."
|
|
|
|
-- J.C. Cirlot, _A Dictionary of Symbols
|
|
|
|
|
|
During his campaign, Bill Clinton repeated his goals to foster high
|
|
technology and improve our nation's infrastructure. ISDN is both - it's the
|
|
totally digital public information highway, capable of carrying phone conver-
|
|
sations, computer/fax data, live video, and lots more. It's the global nervous
|
|
system for the twenty-first century.
|
|
|
|
Welcome to the INTEGRATED SERVICES DIGITAL NETWORK. Its proper name may
|
|
turn out to be "The Net."
|
|
|
|
Britain began its web in 1987, with France following in 1988. Last year,
|
|
the US began full-scale implementation. Now AT&T, MCI, and Sprint all connect
|
|
to the network. It's also running in Germany, Belgium, Japan, Denmark,
|
|
Switzerland, Singapore, Spain, Sweden, Norway, Italy, Hong Kong, Australia, and
|
|
the Netherlands.
|
|
|
|
The Consultative Committee for International Telephone and Telegraph
|
|
defined ISDN. The CCITT are the people from the International
|
|
Telecommunications Union who hammered out all the details that will let you
|
|
call any county's ISDN network without any hassles. These standards spell out
|
|
the particulars of the physical connectors as well as basic supplementary
|
|
services, and let you use 64 kbps ISDN channels to call both digital and analog
|
|
customers.
|
|
|
|
All of which to be explained shortly. The thing to keep in mind about
|
|
ISDN standards is that they describe an all-digital, multichannel system with
|
|
out-of-band signaling for use around the world.
|
|
|
|
ALL-DIGITAL means that everything traveling across the network is, on a
|
|
basic level, nothing but binary bits. You know, ones and zeros, that kind of
|
|
thing. Even voice communications will be digital. This makes for clearer data
|
|
transmission, which really means more efficient conversations between computers
|
|
and very crisp phone quality.
|
|
|
|
MULTICHANNEL means that you've got more than one communication line open
|
|
to you simultaneously. Think of it as having two or more phone lines instead
|
|
of one. Call waiting isn't multichannel, because you can't talk to both
|
|
callers at the same time. Neither is 3-way calling, because all of you have to
|
|
talk on the same channel. If you've got 2 separate channels, you can call
|
|
another computer and talk to your mom over the phone at the same time, using
|
|
the same hookup.
|
|
|
|
OUT-OF-BAND SIGNALING is a little harder to describe. But let's compare
|
|
it to what we have now with analog circuits: in-band signaling. Currently, the
|
|
same phone lines that you talk on are the ones that the switching systems use
|
|
to locate free trunk circuits for your calls.
|
|
|
|
This is what made blue boxing possible - you could pretend that you were a
|
|
phone computer by sending the sounds that the switching equipment figured could
|
|
only come from authorized machinery. The systems couldn't tell that the box
|
|
tones weren't legitimate routing instructions, so you could call anywhere for
|
|
free.
|
|
|
|
Well, so much for that. Out-of-band signaling means that the routing
|
|
information used by the switching equipment travels on its own channel,
|
|
parallel to the network. This will render blue boxes fossil artifacts.
|
|
|
|
ISDN hookups come in two styles, one for small uses and the other big
|
|
ones.
|
|
|
|
The "small" configuration is called the BASIC RATE INTERFACE. With a BRI,
|
|
you get access to two "bearer" channels and one "data" channel. Because of
|
|
this, many people refer to the BRI as a 2B+D hookup - just get used to it.
|
|
You'll use BRI connections for small key systems, PBXs and individual terminals
|
|
(desktop computers, low-end video conference units, hi-fi audio conference
|
|
units, fax machines, etc.). In other words, this is what you're going to have
|
|
at home.
|
|
|
|
The BEARER CHANNELS each offer a bandwidth of 64 kilobits per second, or
|
|
kbps. That means you can send 64,000 bits of information each second on a B
|
|
channel. In modem speak, one bit per second equals 1 baud. Regular phone
|
|
lines have a bandwidth of about 19.2 kbps, or 19,200 baud.
|
|
|
|
B-channel information has no defined protocols or restrictions. France
|
|
Telecom's _ISDN: A User's Guide_ says "They are simply 'transparent,'
|
|
circuit-switched data pipes, and can provide a connection between any two users
|
|
on the network, anywhere in the world served by ISDN." In other words, you're
|
|
free to compress and encrypt information for network transmission.
|
|
|
|
Not only that, but you can use both B channels at once for sending or
|
|
receiving information, effectively doubling the bandwidth to 128 kbps.
|
|
|
|
The DATA CHANNEL is for signaling, mostly. In a BRI, its bandwidth is 16
|
|
kbps. If you want, you can actually send computer data across it at 9.6 kbps;
|
|
however, apparently large information blocks would travel in spurts, depending
|
|
on switching traffic density. Recommended uses for sending data over the D
|
|
channel are for burglar alarm reports, credit card inquiries, stuff like that.
|
|
|
|
The other configuration for an ISDN hookup is called the PRIMARY RATE
|
|
INTERFACE. Instead of a 2B+D setup, the PRI consists of 23 B channels at 64
|
|
kbps and one D channel, also at 64 kbps. Many people will refer to the PRI as
|
|
a 23B+D. (In Europe, the PRI is 30 B channels and a D channel. Who cares?
|
|
It's all compatible.)
|
|
|
|
People are using PRIs to connect medium and large PBXs, multiplexers and
|
|
mainframes to the network. (France Telecom's pamphlet says "ISDN multiplexers
|
|
can be used to connect several pieces of equipment {a PBX, LAN, mainframe,
|
|
video conference unit or the like} to one PRI. They also allow for n x 64kbps
|
|
bandwidth-on-demand applications such as video conferencing and LAN
|
|
interconnection." Sounds cool.)
|
|
|
|
At press time, AT&T and some local telcos are the only people you can get
|
|
BRI connections from. MCI and Sprint, as far as I can tell, only offer the PRI
|
|
configuration. I'm not 100% solid on this, because MCI and Sprint headquarters
|
|
haven't returned my calls.
|
|
|
|
Whatever configuration you're using, there are specified supplementary
|
|
services that all ISDN carriers are capable of offering, depending on local
|
|
regulations. They're the Integrated Services of the Digital Network.
|
|
|
|
o CALLER IDENTIFICATION tells the called party the caller's phone number. It's
|
|
usually called Automatic Number Identification or Calling Line ID. (In
|
|
California, the Public Utilities Commission has approved Caller ID only if
|
|
the telco also offers line blocking, absolute blocking, and per-call
|
|
blocking. For various reasons, the California carriers aren't offering any
|
|
CLI services for now.)
|
|
|
|
o USER-TO-USER SIGNALING allows you to specify 32-character messages to be
|
|
displayed with the standard D-channel SET-UP, CONNECT, DISCONNECT, or RELEASE
|
|
MESSAGES.
|
|
|
|
o CALL DEFLECTION lets you refuse a call and reroute it to a different number,
|
|
specified in your refusal message.
|
|
|
|
o SUBADDRESSING allows you to specify with an extra four digits which ISDN
|
|
device at a customer's PBX you want to connect with. A phone, or a fax
|
|
maybe, whatever.
|
|
|
|
o CALL HOLD allows you to put someone on hold. Then you can make a new call,
|
|
or pick up the old one, whatever.
|
|
|
|
o TERMINAL PORTABILITY lets you put a call on hold for three minutes, during
|
|
which time you can pick it up again at a different place.
|
|
|
|
o ADVISE OF CHARGE lets you know at any time how much this call is going to
|
|
cost if you hang up now.
|
|
|
|
o CALL TOTAL COST tells you after you hang up how much money you wasted
|
|
downloading GIFs.
|
|
|
|
o GLOBAL CALL FORWARDING is self-explanatory.
|
|
|
|
o CALL WAITING informs you someone's waiting to talk to you, along with their
|
|
phone number and anything specified in the CONNECT D-channel message.
|
|
|
|
o CALL-BY-CALL SERVICE SELECTION lets a PRI customer reallocate his/her B
|
|
channels to different devices at will, as well as add and subtract lines.
|
|
|
|
o CALL REDIRECTION lets companies set up computerized rules for call spillover.
|
|
For instance, a branch on the East coast might automatically redirect calls
|
|
to West coast offices after 5:00 PM EST.
|
|
|
|
|
|
Details, Details
|
|
|
|
Your central office, or local switch, is that fenced-off telco building
|
|
probably eight or ten blocks away from your house. You can't pay your bill
|
|
there, because its basic function is to house the equipment which connects you
|
|
and your neighbors to other COs and long distance lines.
|
|
|
|
For you to get hooked up to the ISDN, your local switch needs Signaling
|
|
System 7, a protocol that the FCC has required to be installed nationwide by
|
|
April of 1993. The other thing it needs is the latest and greatest equipment
|
|
for handling calls.
|
|
|
|
In the San Francisco Bay area, that means either 5ESS or DMS100. 5ESS is
|
|
the fifth version of AT&T's Electronic Switching System. DMS100 is Northern
|
|
Telecom's baby. In 'Frisco, there are only 3 COs with advanced digital
|
|
switching (Bush-Pine, Market, and Folsom) - they all use the DMS100. South San
|
|
Francisco, the airport, San Jose, and the East Bay all use 5ESS.
|
|
|
|
Other companies make advanced digital switches, not just AT&T and Northern
|
|
Telecom; for instance, Siemens, NEC, and Fujitsu. But you see the same types
|
|
again and again because, like for any equipment, it's cheaper buying in
|
|
quantity.
|
|
|
|
If your CO hasn't been upgraded to digital yet, you probably have an old
|
|
AT&T analog switch, 1AESS. These were built and installed before Ma Bell took
|
|
a few hits from the antitrust-law hatchet. Apparently, the 1A's are really
|
|
tough and have a 100,000 line capacity. They can do call waiting, call
|
|
forwarding, etc., but not ISDN.
|
|
|
|
Instead, they support a service called SDS-56, or Switched 56. It's the
|
|
phone company's incomplete solution to the bandwidth bottleneck of regular
|
|
phone lines. It provides a single channel at 56 kbps. If you want to use the
|
|
line for simultaneous voice and data, you need special equipment on both sides
|
|
of the connection.
|
|
|
|
Also, because Switched 56 employs in-band signaling, typical set-up time
|
|
for international calls is between 30 and 40 seconds, compared to 4 or 5
|
|
seconds for international ISDN calls. Despite these shortcomings, more
|
|
customers have Switched 56 than ISDN now, because of availability.
|
|
|
|
|
|
Now What?
|
|
|
|
Let's say your local switch is all set for ISDN. You shell out the
|
|
installation fee (currently about $800), and you're all wired-up.
|
|
|
|
Your ISDN circuit begins at the wall with a mundane RJ11 jack. (That's
|
|
the kind you're used to now.) You connect that to a box called a NETWORK
|
|
TERMINATING INTERFACE, or NT1. The specific NT1 you need depends on the type
|
|
of switching at the CO: 5ESS, DMS100, whatever. Out of the NT1 comes a nifty
|
|
4-wire RJ45 plug, that looks essentially like the RJ11 but has an extra square
|
|
bump on the side so you can't stick it into an RJ11 socket. (You _can_ push an
|
|
RJ11 plug into an RJ45 socket, but nothing will happen.)
|
|
|
|
The mutant RJ45 plug goes into a TERMINAL ADAPTER, which could be a
|
|
stand-alone box or built into an ISDN device (typically a digital phone, video
|
|
conferencing hookup or ISDN computer card). You'd want a stand-alone terminal
|
|
adapter if you had a lot of ISDN devices sharing one outlet. Many adapters and
|
|
devices have one or two RJ11 sockets so you don't have to throw away your
|
|
analog phone - you can use them in your circuit. And, as long as you pay your
|
|
bill, you're set.
|
|
|
|
Right now, though, ISDN has limited availability, mostly in downtown areas
|
|
of major cities. That's because most of the customers are research &
|
|
development firms and Fortune 500 companies. Otherwise, ISDN is being marketed
|
|
mainly for Community of Interest applications. This means groups out that
|
|
could use quick data exchange, like lawyers, realtors, and bankers, for whom
|
|
ISDN would be a good idea.
|
|
|
|
Big players in the computer industry (Apple, IBM, Hewlett-Packard, DEC)
|
|
are developing terminal interfaces for their computers and other products.
|
|
|
|
Apple, for example, has released a Macintosh ISDN NuBus card. (Although
|
|
the product doesn't recognize standard telephone DTMF noises, third-party
|
|
developers are using software work-arounds to get it to function.) Compression
|
|
Labs, Inc. makes the Teleos Mac Terminal Adapter/Series 100, and Hayes sells
|
|
what it calls the ISDN Extender (which I think is also a terminal adapter).
|
|
|
|
Terminal adapter cards are now about $900, but eventually the prices
|
|
should fall to about $50 when someone miniaturizes it to a single chip.
|
|
|
|
|
|
Meet George Jetson...
|
|
|
|
Many large and medium-sized companies are using video conferencing systems
|
|
instead of traveling for meetings. That way, they save a lot of travel time
|
|
and expense.
|
|
|
|
If you're interested in doing serious video conferencing stuff, you need
|
|
what's called a CODEC (coder/decoder). The one I saw at PacBell was about the
|
|
size of a dinky 1.2 cubic foot refrigerators you see all over the dorms. These
|
|
things process video information going both ways over ISDN or Switched 56
|
|
lines.
|
|
|
|
Most systems let you step between sampling rates of 112 kb to 384 kb or
|
|
higher.The higher the transfer rate, the more B channels from a PRI you need,
|
|
and the better the quality in resolution and motion. These systems range
|
|
between about $15,000 and $100,000.
|
|
|
|
Of course, if you don't have tens of thousands of dollars to throw at a
|
|
dedicated video conferencing box, you might want a PC-based system. Two
|
|
outfits that produce video conferencing systems are PictureTel and Compression
|
|
Labs, Inc. Both of them make video interfaces for the IBM and Macintosh,
|
|
respectively, as well as full-scale video conference systems.
|
|
|
|
When are we going to see home video phones? Well, AT&T already
|
|
manufactures one for regular phone circuits, but it's practically a waste of
|
|
money. It's not until blanket ISDN implementation that you'll be able to see
|
|
the called party in realistic motion and color.
|
|
|
|
The problem is, practically no one has a BRI hookup. Therefore, no one's
|
|
producing ISDN home video phones. Which means that even if the phone company
|
|
offered BRI service, you wouldn't want it, which further still squelches
|
|
home-user products. Don't hold your breath for a cool ISDN video phone; it may
|
|
take a while.
|
|
|
|
In case you've been wondering, ISDN will not be able to carry high
|
|
definition television signals - the HDTV bandwidth is way too big to be
|
|
practical. The only way you'll get HDTV is over the airwaves or from your
|
|
cable company.
|
|
|
|
Regular TV signals may be another story, but if the FCC isn't kidding,
|
|
then we should see the end of all NTSC television broadcasts by about the year
|
|
2008. In that case, there won't be any regular TV programming to pump over the
|
|
ISDN, unless you want to copy old videotapes over the network.
|
|
|
|
|
|
I Can't Think of A Good Subheading
|
|
|
|
CENTREX(TM) is the name that PacBell gave to its PRI service. PacBell
|
|
also throws in an extra feature, called VIRTUAL KEY SYSTEM.
|
|
|
|
If your place of business can internally route calls (meaning: put them on
|
|
hold, transfer them to other peoples' desks), then you've got some kind of key
|
|
system. You know that closet containing the wall-mounted rack with telephone
|
|
wires snaking around the little metal posts? Probably next to the rack, on the
|
|
floor or attached to the wall, is a box. This box probably has a name painted
|
|
on it, possibly Merlin(TM).
|
|
|
|
Anyway, this box handles all of the details when you put a call on hold,
|
|
or whatever. It does the dirty work. With this service, you can transfer
|
|
calls, put them on hold, just like using the box, except there _is_ no box.
|
|
All of the neat features happen inside the computers at your CO.
|
|
|
|
Of course, CENTREX(TM) supports service selection, so you can change your
|
|
configuration really quickly. If you have seasonal business cycles, you can
|
|
order less lines for your virtual key during the slow months and more lines
|
|
during the busy ones. And you're not stuck with a piece of machinery that
|
|
you'd have to sell if your business outgrows, say, a 20-line capacity.
|
|
|
|
Another cool feature of CENTREX(TM) service is called "call appearance."
|
|
It lets one B channel appear to be 15. Let's say you have call appearance, and
|
|
30 friends call you at the same time. Okay, you have a BRI hookup at home,
|
|
which (if you remember) has two B channels. If you have two ISDN phones, you
|
|
can carry on two separate conversations at once. The trick is, you can also
|
|
put someone on hold and talk to somebody else waiting to hear your voice. Each
|
|
B channel can have 15 people on hold while you're talking to somebody.
|
|
|
|
This is perfect for pizza delivery places, because for a monthly charge of
|
|
$25, they get what amounts to 30 lines, with two people taking orders at a
|
|
time.
|
|
|
|
|
|
Compu$erve On Growth Hormones
|
|
|
|
Eventually, we should see the advent of huge, international online
|
|
services that'll crush even Compuserve - actually, they'll probably be the ones
|
|
to sponsor it. Nowadays, only the nub-heads with modems can romp around
|
|
bulletin boards and the Internet. Soon, practically anyone will be able to do
|
|
it, probably even from payphones. These services will have to be gigantic,
|
|
monstrous things. Gives me the creeps, actually.
|
|
|
|
In France, their version of this is called Minitel. I think it's
|
|
primarily a nationwide email system. Apparently it's a big hit with average
|
|
citizens and university students. I bet that the day Compuserve ISDN goes
|
|
online, half of the people you talk to will be named Michel or Claire.
|
|
Minitel's had a big impact on student organizing - a couple of years ago French
|
|
university students put together a nationwide anti-government demonstration
|
|
to protest some unpopular decision or other. My memory isn't that good, all
|
|
right? I think it was either the government planned to close some schools or
|
|
raise tuitions. Anyway, thousands of students across the country took to the
|
|
streets the next day, and the government reversed its decision. The protest
|
|
organizers credited the Minitel system for a large part of their success.
|
|
|
|
|
|
Daddy, I Want An Oompa-Loompa _now_!
|
|
|
|
I spoke to only one person who was willing to guess when ISDN will be
|
|
largely implemented. His estimate for widespread California implementation is
|
|
2 or 3 years. Much of the East Coast is already wired for it, so the New
|
|
Yorkers will be playing with it sooner.
|
|
|
|
According to people at the California Public Utilities Commission, PacBell
|
|
intends to have all of its COs digital in four years. The program is called
|
|
ATD97 - Advanced Technology Deployment by 1997. All PacBell COs would then be
|
|
capable of ISDN. Not only that, they'll be throwing away the loading coils in
|
|
the phone circuits which analog switches need to boost signals, but are
|
|
incompatible with digital ones.
|
|
|
|
The salespeople at PacBell said that one reason they haven't already
|
|
upgraded their COs to provide ISDN is that the Public Utilities Commission has
|
|
to approve any proposed changes. This isn't true. According to the people I
|
|
spoke to at the PUC, since 1 January 1990, the phone carriers are free to do
|
|
this kind of upgrade without any oversight or approval. In fact, they're
|
|
encouraged to take financial risks of this type.
|
|
|
|
What about the Europeans? They've got a big ISDN network chugging along
|
|
already. Why won't the American telcos push as hard as the foreign ones?
|
|
|
|
The difference is that many foreign countries have a nationalized
|
|
telephone service. France is home to the flagship ISDN system, Numeris. The
|
|
French government decided in 1988 to tear out the old phone system and install
|
|
the all-digital version. In less than three years, they replaced virtually
|
|
every part of the French system and went so far as to _give_ every customer an
|
|
ISDN terminal. The terminals came with a telephone handset, keyboard and
|
|
screen.
|
|
|
|
To further speed people's acceptance and use of the system, the government
|
|
stopped printing bus schedules and telephone books on paper - now that
|
|
information is solely available over the network.
|
|
|
|
Unfortunately, _this_ mountain isn't coming to Mohammed - you aren't
|
|
likely to get a free ISDN terminal in the US. It's not how we do things here.
|
|
But, who knows? I guess it depends on how badly the telcos want to push it.
|
|
|
|
Personally, I can't wait. That's what made the ISDN hunt so exasperating.
|
|
I'm disappointed that it's taking so long for the US to get into this
|
|
technology. We didn't even adopt the standard until 1991, four years behind
|
|
the French.
|
|
|
|
If you want ISDN, you've got to hunt it down. Call your telco accont
|
|
executive and ask if your central office supports ISDN. If not, ask when it's
|
|
supposed to happen.
|
|
|
|
If you call France Telecom and ask nicely, I bet they'll send you a copy
|
|
of their _ISDN: A User's Guide_. It does a nice job of explaining the standard
|
|
and applications, and it also has a great glossary of terms. France Telecom's
|
|
main US office is in New York.
|
|
|
|
Maybe the best thing you could do is talk to that friend of a friend of
|
|
Bill Clinton's you used to know. Or mail a copy of this article to the White
|
|
House. Perhaps the right person there, eager to make good on campaign
|
|
promises, will steer the country toward a worthy infrastructure investment -
|
|
the national implementation of the ISDN.
|
|
_______ __________________________________________________________________
|
|
/ _ _ \|Demon Roach Undrgrnd.806/794-4362|Kingdom of Shit.....806/794-1842|
|
|
((___)) |Cool Beans!..........510/THE-COOL|Polka AE {PW:KILL}..806/794-4362|
|
|
[ x x ] |The Alcazar..........401/782-6721|Moody Loners w/Guns.415/221-8608|
|
|
\ / |The Works............617/861-8976|Finitopia...........916/673-8412|
|
|
(' ') |ftp - zero.cypher.com in pub/cdc |ftp - ftp.eff.org in pub/cud/cdc|
|
|
(U) |==================================================================|
|
|
.ooM |Copr. 1993 cDc communications by Reid Fleming 04/01/93-#228|
|
|
\_______/|All Rights Drooled Away. SIX GLORIOUS YEARS of cDc|
|
|
|