Hacker Chronicles 2 (Alt)/The_Hacker_Chronicles_Volume_II-CD2.iso/td2/td14_53.txt

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TELECOM Digest     Mon, 31 Jan 94 14:45:30 CST    Volume 14 : Issue 53

Inside This Issue:                          Editor: Patrick A. Townson

    Re: INTERNET Connections: What's Involved? (Lars Poulsen)
    Re: Real Time Audio Compression (Ketil Albertsen)
    Re: ISDN NT1 Power Source (Bob Larribeau)
    Re: Informing Ourselves to Death (Tom Horsley)
    _Technopoly_ by Neil Postman ([e-mail])
    Brendan Update and His "Thanks" (CuD via Monty Solomon)
    How to Make a Sun Send Messages to a Pager or a GSM Phone (Jurgen Debedts)
    DID Questions (Thomas Tengdin)
    Data Over Power Lines (Stewart Fist)
    Cheap PBX For Home - Where? (Frank Keeney)
    Internet E-Mail Access in Mexico (Jeremie Kass)
    ISDN and Caller-ID (Will Martin)
    Pac Bell and the Earthquake (The Network Group)

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----------------------------------------------------------------------

From: [e-mail] (Lars Poulsen)
Subject: Re: INTERNET Connections: What's Involved?
Organization: CMC Networ.|k Products, Copenhagen DENMARK
Date: Mon, 31 Jan 94 08:04:52 GMT


In article <[e-mail]> [e-mail].
ca (J. Guitard) writes:

> I would like some info on what's involved in connecting to the
> Internet. At first I thought the only way to connect was through a T1
> line, but now I hear you can connect with a 9600 baud line. Someone
> told me they were connected through their local internet provider. Who
> are these local internet providers? What are the costs for these
> lines and monthly fees, etc?  Email me or post here.

Since you are posting from the computer science department of a
Canadian University, I presume that you already are Internet connected
at school, and your question is directed more towards "How can a
person get a personal Internet connection that does not depend on
Government sponsored privileges". The answer is that there are a
variety of multi-user systems with Internet access on which you can
get accounts.

At the low end, there are bulletin boards, such as FIDONET systems
that are often operated on a free volunteer basis, although the owners
will be happy to accept a small donation to offset their costs.  These
systems tend to have only electronic mail connections to the Internet.
You can connect to these systems using modems from 1200 bps to 14400
bps.

In a way, the large North American BBS systems, like CompuServe,
Genie, America Online or Prodigy represent the same idea taken to the
utmost. While these systems have local access numbers, even in middle-
sized cities, they tend to have more information available but at a
higher cost. Typically, at least USD 5 / hour. They also have
email-only connections to the Internet, although this is slowly
beginning to change.

The next step up, tends to be community organized Unix systems. Often
these will give you a full unix shell, and many of them have full
Internet connections.  You can connect to these systems using modems
from 1200 bps to 14400 bps. A widely circulated list of these systems
is known as the PDIAL list.  In the larger cities, it is not unusual
to be able to get an account that allows you 20 hours of connect time
for USD 20 per month or USD 75 for unlimited access. On the other
hand, if it takes a long distance call to connect to it, the telephone
charges will cost much more than the service. Indeed, some systems are
totally funded on kickbacks from long distance carriers.

In both of the above examples, your connection would be a plain
terminal connection. The Internet service extends only to the access
node, and after FTP-ing a file to the access node, you would have to
download it to your own PC or Mac using the file transfer features of
your terminal program (Kermit, Zmodem etc). For a bit more money, your
could have your own machine become a real Internet node while you are
online, using a link protocol such as SLIP or PPP. This will allow you
to use the newer "Information Navigators" such as Mosaic, and also to
FTP directly to your hard disk. Unless your connection is full-time,
you will still need to keep your mailbox on the (unix) access host,
although you can use a nicer client (such as Eudora) to download it
transparently when you connect up. These connections are generally at
14400 bps. Because the service provider needs to install more
equipment and usually ends up needing to give more support to these
users, this service is more expensive than login service. Typical
rates would be $200 per month for unlimited access. (If you can get to
the access port with a "free" local call from home, this is a very
economical way to become a "real" network node.)

Finally, you can attach a whole cluster of systems on a local area
network (LAN) to the Internet, either in dial-on-demand mode, or on a
full-time leased line. Such access can be at any speed from 9600 bps
to T-3 depending on your needs and budget. This class of service is
generally of interest to businesses. Service on a 56kbps access line
is generally available for USD 1000 per month at any long distance
carrier's point of presence (POP); i.e. you have to add the cost of a
leased line to that point.

There is a whole industry of network service providers, ranging from
the above mentioned FIDOnet amateurs to specialized carriers with
annual sales of tens of millions of dollars. Some of them are local
co-operatives, often affiliated with local colleges. Some are regional
carriers, originally founded as groups of colleges banding together to
link up the schools to NSF-net, and later opening up membership to
businesses and individuals. Some of these have expanded to offer
service anywhere in the US. And some are spin-offs from telephone
companies.

Since there are literally hundreds of vendors, I can only mention a
few of the large ones:

   PSI.COM - Performance Systems International, in Troy, NY
 and with a sales office in Tyson's Corner, VA
   ALTER.NET - UUNET Technologies, in VA
 and with a Canadian branch in Ontario
   ANS.NET - Advanced Networks and Services, in Elmsford, NY

Both PSI and ALTERnet offer everything from dialup-login to leased
line packet service. ANS tends to go after the very large customers.


Lars Poulsen   Internet E-mail: [e-mail]
CMC Network Products  Phone: (011-) [phone]
Hvidovre Strandvej 72 B Telefax:      [phone]
DK-2650 Hvidovre, DENMARK Internets: designed and built while you wait

------------------------------

From: [e-mail] (Ketil Albertsen,TIH)
Subject: Re: Real Time Audio Compression
Organization: T I H / T I S I P
Date: Mon, 31 Jan 1994 09:33:00 GMT


In article <[e-mail]>, daveb@jaws (David Breneman)
writes:

> [...]  Still, there is no way to "compress" analog audio to
> get a greater frequency response than the wire it's travelling down.

Quite a few years ago, I read about experiments done in Eastern
Europe: They have (had?) almost exclusively AM broadcast transmitters.
Researchers were investigating alternatives for obtaining better sound
quality in a cheaper way than building up an all-new FM transmitter
network.

The research showed that the human ear is surprisingly insensitive to
small frequency variations in the higher harmonics -- any frequency in
the approximately correct range will be subjectively perceived as
overtones.

Also, while US AM broadcasts have a 9 kHz bandwidth, European ones
have only a 6 kHz bandwidth (Are these figures correct? I believe so,
but this is really too far away from my field of expertize!). This
applies to the consumer (and studio) equipment, though -- the
transmission equipment is "international", capable of handling 9 kHz.

So the following solution was tried: Anything below 5.5 kHz was
transmitted as before. Frequencies from 6.5 to 20 kHz was split into a
dozen frequency bands. The *total* energy in each band steered the
level of a *pure tone* transmitted in 6.5-9 kHz range, like the stereo
pilot tone, but each band had its pilot tone. Obviously, the pilot
tones where more closely spaced than the bands, in order to fit into
2.5 kHz!

An old 6 kHz receiver would filter the pilot tones away. A new HiFi
receiver would contain a dozen of white noise generators (with a
frequency range limited to the corresponding frequency band) whose
intensity was directly steered by the pilot tone for that band.
Listening tests indicated that the perceived music reproduction
quality was, although not quite as good as FM, dramatically improved.

I never heard of this system being put into use, though. At time of
writing it was not yet clear whether a sufficiently high percentage of
consumer receivers in use actually did filter away everything above 6
kHz - if not, the listeners would be hearing a lot of high pitched
noise, making it unacceptable. It could also be that the filters and
white noise generators necessary in new HiFi receivers to exploit the
higher quality sound turned out to be too expensive to be acceptable.
Or it could be that the AM sensitivity to environment noise made it
less interresting, after all.

Yet, these experiments did show one (more or less) viable approach,
from a technical point of view, to analog sound compression to lower
bandwidth requirements.

------------------------------

From: Bob Larribeau <[e-mail]>
Subject: Re: ISDN NT1 Power Source
Date: Mon, 31 Jan 94 11:14:05 -0800


> [e-mail] (sohl,william h) writes:

>> In article <[e-mail]>, Paul D. Guthrie
>> <[e-mail]> wrote:

>>> I'm looking for a couple of answers about some ISDN questions that
>>> experience and Stalling's ISDN book have both left me unclear on.
>
>>> First, a CPE can be line powered (the AT&T 7506 e.g.), but my
>>> experience with NT1's are that they must be DC powered (but I've only
>>> dealt with rack mounted units).  Can NT1's be line powered?

>> I am unaware of any "line powering" of ISDN CPE in the USA.  Perhaps
>> what is meant by "line powering" of the AT&T 7506 is that the NT-1 and
>> associated power supply is located in a telephone equipment closet
>> somewhere at a customer location and that is the power supply for the
>> 7506.

> This is quite surprising.  The standards were arranged around some
> (limited) power feeding at 60V.  This power is(was) intended to supply
> sufficient power to drive one (and only one) TA attached to the "S"
> bus of the NT1 (2B1Q to "S" Bus interface).  The power for this
> "special" device is supplied by an extra pair on the S bus reserved
> for it, or by reversing the polarity of the normal power feed supplied
> in Cailho fashion on the Rx and Tx pais of the "S" bus.  In this
> manner, an ISDN telephone for, instance, would draw power from the
> normal Cailho feed and the reserved pair, or by use of a bridge from a
> reversed polarity Cailho feed.

> Are you sure that a 60V feed (max current of about 20-30ma) is not
> provided bu US Telcos, not even to power repeaters (if required)?
> Excuse me for being scheptical, but I'm not convinced, but then I am
> an Australian so "what would I know?".

I am going to finally give in to temptation and jump into this one.
You must remember that in the U.S. we use the U-interface, which is a
two-wire local loop interface.  The U-interface, as implemented in the
U.S., does not provide power from the network.  Powering is the
customer's responsibility.

There are various options that customers in the U.S. can use for
providing power to the T-interface.  T-interface ISDN telephones in
the U.S. commonly use this customer provided line power as their power
source.  Many ISDN data terminal do not use the T-interface line power
but use a separate power receptacle.

Hope this helps.  I understand that from your perspective we always
get things upside down:-)


Bob

------------------------------

From: [e-mail] (Tom Horsley)
Subject: Re: Informing Ourselves to Death
Date: 31 Jan 1994 13:39:39 GMT
Organization: Harris Computer Systems Division


I am glad to see this response by George Gilder, he said it better
than I could.

When I read Postman's comments, I was reminded of a character
described in Arthur C. Clarke's book "The Fountains of Paradise". He
was talking about some 18th century professional quack (who's name I
forget), who went around opposing things like trains with a bunch of
psuedo science babble about how the breathtaking speed would be bound
to psycologically damage the travellers.


domain: [e-mail]       USMail: Tom Horsley
                                               511 Kingbird Circle
                                               Delray Beach, FL  33444


[TELECOM Digest Editor's Note: I did not get quite the same impression
of Postman's speech that you and Gilder recieved. I do not think
Postman said computers were dangerous, only that they could be misused
and too much reliance could be placed in them. At least one other person
enjoyed Postman's meditation, as the next letter in this issue will
reveal.  PAT]

------------------------------

From: [e-mail]
Subject: _Technopoly_ by Neil Postman
Date: Mon, 31 Jan 94 15:20:08 EST
Organization: The MITRE Corporation, McLean VA 22102


For those of you who liked Neil Postman's "Informing Ourselves to
Death" you might like to know that it is revised and included as a
chapter in his book _Technopoly, The Surrender of Culture to
Technology_ published in 1993 by Vintage/Random House, ISBN
0-679-74540-8 in paperback.  I found it to be a relatively quick and
enjoyable read. Your mileage may vary.


DW

------------------------------

Date: Mon, 31 Jan 1994 01:43:27 -0500
From: Monty Solomon <[e-mail]>
Subject: Brendan Update and his "Thanks"


FYI.  Excerpt from Cu Digest #6.11

  Date: Sat, 29 Jan 94 21:09:22 PST
  From: [e-mail](Sun Ming Lieu)
  Subject: File 1--Brendan Update and his "thanks"

((MODERATORS' NOTE: The following update on Brendan Kehoe, author of
ZEN AND THE ART OF THE INTERNET, CuD ftp archmeister, and
cyberdenizen, is great news. We've also received two posts from him,
and he sends along "THANKS" for all the posts.  We mailed off the
collection of e-wishes this week, and thanks to all those who
contributed)).

Brendan continues to make phenomenal progress in the last few days.
His neurologist says that she has not seen a case like this in 12
years of practice.

The hospital is letting Brendan out on extended passes, and so he has
been visiting the hotel where his mother and brother are staying,
eating out, and other outings.  He will be moving to the Spaulding
Center at Mass General in Boston on Tuesday (Feb 1).  The injury to
his ear was not as serious as originally expected - he can hear from
it and it is okay for him to fly.

I talked with Brendan for about 10 minutes by phone today.  He and
Jeff sprung it on me when Jeff called and was I surprised!  Brendan
just came on the line saying "This friend of mine who is working in
California thinks you would like to talk to me" and started to talk up
a storm.  He's been reading his mail and kept talking about how much
g++ traffic there has been and how eager he is to go back to work.  He
sounded happy and excited.  We talked about the weather in
Philadelphia, flying first class, living closer to the office so he
wouldn't have to commute from Santa Cruz, the earthquake in Southern
California, and so on ...

Brendan wants to be done with the 2-3 weeks in Spaulding and be back
in California as soon as possible -- he says end of February, although
everyone is telling him to hold his horses and not count on it quite
so soon.  Does he know something we don't?


Sun Ming

------------------------------

From: [e-mail] (Jurgen Debedts)
Subject: How to Make a Sun Send Messages to a Pager or a GSM Telephone
Reply-To: [e-mail]
Organization: B.I.M.
Date: Mon, 31 Jan 94 08:16:28 GMT


I'm looking for something quite special:

We would want to have our Sun, (which is running critical
applications), dial-out to a semascript pager to tell the sysadmin
something is wrong. Typically, we have some sort of contool, which
send a certain fixed message for a certain error-situation. This
messages would then in fact be send to a modem that dials up a
semascript pager, and passes on the error.

In our dreams we would like to go even further, and have the Sun dial
up a GSM telephone, and have the Sun speak to the sysadmin saying that
there is a problem. (pre-recorded fixed messages). In this case, we
thought of have a modem that directly dials up a GSM mobile telphone.
But there are some problems to be solve with this: for example, a GSM
will not give a Carrier Detect, only a connect signal. Anybody delt
with this kind of problems before?

Does anybody out there know of software that does one of these two
things, or does anybody have some tips, or thoughts he or she would
like to share with me?  (Like which modems could we use, etc)
The software may be commercial or public domain.

I would greatly appreciate any feedback.

Thanks in advance.


Regards,

Debedts Jurgen
e-mail : [e-mail] (or uunet!mcsun!ub4b!sunbim!jdb)
BIM sa-nv   Kwikstraat, 4   B-3078 Everberg Belgium

------------------------------

Date: Sun, 30 Jan 1994 23:34:33 -0800
From: Thomas Tengdin <[e-mail]>
Subject: DID Questions


Can anyone tell me how DID lines pass the number down the trunk?

Either an explanation or a pointer to an old issue of the Digest would
be great.


Tnanks,

T3

------------------------------

Date: 31 Jan 94 07:37:08 EST
From: Stewart Fist <[e-mail]>
Subject: Data Over Power Lines


Thomson, under the RCA brand, has just released a product that allows
you to plug a telephone into the power lines and use it as an
extension line within a house or building.  This should allow data
over power lines between two PCs.

The product is called Intelejack.  The master control unit costs about
US$150, and the extender about half as much.  The phone/modem plugs
into this extender using a normal RJ11 plug.  You can have any number
of extenders for voice use.  You could probably connect Macs over this
system using PhoneNet, if it isn't too noisy.

------------------------------

From: [e-mail] (Frank Keeney)
Reply-To: [e-mail]
Date: Mon, 31 Jan 1994 10:26:08 -0800
Subject: Cheap PBX For Home - Where?
Organization: Calcom Communications, [phone]


I'm looking for an inexpensive PBX system for my home. Something that
will work with two or more CO lines and more than five extensions.

Anybody know where I can find something like this?


Frank Keeney                   | E-mail  [e-mail]
115 W. California Blvd., #411  | Fidonet 1:102/645
Pasadena, CA 91105-1509 USA    | UUCP    hatch!calcom!frank
                               | FAX     [phone]
                               | Voice Mail [phone] x402
* Origin: yume no naka ni... (1:102/645)

------------------------------

From: [e-mail] (Jeremie Kass)
Subject: Internet E-mail Access in Mexico
Date: Mon, 31 Jan 94 8:41:31 EST


Does anyone know if it's possible to get access either via a radio
modem or some other way to Internet e-mail.  This is just temporarily,
while I'll be vacationing for a week.  I believe the resort is on the
western (Pacific) coast.

Thanks a lot,


Jeremie

------------------------------

Date: Mon, 31 Jan 94 12:40:16 CST
From: Will Martin <[e-mail]>
Subject: ISDN and Caller-ID


Exactly how does ISDN interact with the legal issues surrounding
Caller-ID?

It is my understanding that making an ISDN connection involves setting
up a header packet or some such initial-connection datastream in which
both the destination and the originator are identified, and that this
identification can have several levels of detail, ranging from nothing
more than the bare phone numbers to a more elaborate chunk of data
that includes free-form text such as a name. If this is true, the
following questions arise:

1) Is the content of this datastream totally under the control of the
caller, or does the telco switch insert its own identifier of the
caller in there somewhere?

2) Can the caller put in false data to make the recipient believe that
the call is coming from somewhere other than it is really originating,
or does the callee use that originator data to establish the return
path, and so providing false data would do nothing but make the
complete ISDN circuit un-creatable? That is, the caller is calling
from site "x", but falsifies the data to say he's calling from site
"y". The callee then tries to respond to site "y" but they're not even
up and on-line, so no connection ever gets established. (What would
happen if site "y" WAS up and on-line, but already communicating with
somebody else? Is there an ISDN equivalent of a busy signal that would
be presented to him?)

3) In states where caller-ID is illegal, is any of this changed? Or
does the telco providing ISDN ignore that or claim that this ISDN data
does not meet the definition of "Caller-ID" as far as the law is
concerned?

I have a basic ignorance of ISDN details, so if all of this is
nonsense as far as real ISDN is concerned, please set me straight! :-)


Regards,

Will      If header address doesn't work, try:
[e-mail] OR [e-mail]

------------------------------

Date: Mon, 31 Jan 94 14:22:00 EST
From: The Network Group <[e-mail]>
Subject: Pac Bell and the Earthquake


A few days after the CA earthquake, Pac Bell started running full page
ad's in the {L.A. Times} offering assistance to displaced businesses
and promoting free installation of business service in homes of
employees to promote telecommuting.

 They offer *FREE* install of Centrex, Business Voice Mail, Call
Forwarding, ISDN and Switched 56. Hummm. I called their 800 number
1800-303-0309 for more information and spoke with a very knowledgable
data specialist re DDs56 & IS DN.

Apparently for $29.95 + tax per month you can get an ISDN line that is
Basic Rate Interface (2B+D). He quoted the maximum price that includes
to B 56Kbps channels + the 9.6 Packet channel on the D. I believe that
the normal installation was somewhere around $800!

I am tempted to go for it, but a little short this week in coming up
with 400 bucks for the ISDN phone.

I asked the technician if Feature Group A Special Access circuits were
also included in the promotion and he said no.

For those that are interested, this promotion is good for orders
placed on or before 2/17/94 in area codes 818 and surrounding codes --
Northern CA does not apply, nor does San Diego.

------------------------------

End of TELECOM Digest V14 #53
*****************************


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