TELECOM Digest     Sun, 24 Apr 94 07:21:00 CDT    Volume 14 : Issue 181

Inside This Issue:                           Editor: Patrick A. Townson

    DID Loophole or I'm Screwed Up?? (Daniel H. Chang)
    Moving Digital Image Data From Mobile Van to Hospital (Douglas M. Tucker)
    Irish and European ISDN Approvals (fitzgeraldj@netc.ie)
    16 Mbps Modem for Real? (maillet@delphi.com)
    MCI Mail Adds Services Available via Internet (mvm@cup.portal.com)
    Job Opportunities in ITI, NCB, Singapore (doreen@iti.gov.sig)
    Channel Bank Recommendations Wanted (Tom Simonds)
    IDB/Peoples Telephone Plan Merger (Fred Bauer)
    Remote Interactive Classroom Instruction - How Far We've Come! (Ralph
Todd)
    ISDN Bridge Advice Please (Dean Banfield)
    DISN Information Request (Rodney Todt)
    Quality of Long Distance Telephone Lines (T.I. Boogaart)
    x.25 Networks (Chris Michael)

TELECOM Digest is an electronic journal devoted mostly but not
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----------------------------------------------------------------------

From: hsingnan@ivo.jpl.nasa.gov (Daniel H. Chang)
Subject: DID Loophole or I'm Screwed Up??
Date: 24 Apr 1994 00:15:58 GMT
Organization: JPL


Hello all-

I am ordering DID service for the first time and have run across a
strange situation. The DID lines ride in our case on eight time slots
of a T1 line. We discovered the following:

* When someone calls one of the DID numbers, we get an appropriate
  A/B signal on our side.

* We are responsible for sending a wink to get the DID digits
  (that works fine), then providing the ring signal on the
  voice band for the sake of the caller on the other end.

* Presumably at some point the intended guy picks up the phone,
  and our equipment seizes the line by raising the A/B bits and
  patches the call.

* Here's the weird part: we discovered that at this point, after
  we've sent the wink and *before* we seize the line, we are able 
  to patch that line to a phone and perform *full duplex* 
  communications through it! We asked Pac Bell about this, who
  said the behavior is normal and the caller is not charged until
  we seize the line, and if we do not seize a timeout will 
  eventually occur. We have determined that timeout is longer
  than ten minutes!

I guess if the DID were carried on analog lines and the PBX had to
supply the ring, then the CO having to offer full duplex is inevitable
since there is no half-duplex in analog. To me this just says that it
is unlikely for the CO to assign the ring responsibility to the PBX --
otherwise the resulting loophole and possibility for abuse seems
enormous!

Can anyone with more experience shed some light on whether what I
described is typical, and what factors am I not taking into account
which would make this the signalling behavior which Pac Bell (and I
presume other RBOC's) finds advantageous to implement?  Some
historical perspective would be really interesting too.


Dan Chang

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

From: dtucker@Erebus.rad.uab.edu (Douglas M. Tucker)
Subject: Moving Digital Image Data From Mobile Van to Hospital
Organization: CIS, Univ of Alabama at Birmingham
Date: Sat, 23 Apr 1994 21:08:56 GMT


Several months ago the radiologists in my department started providing
a mobile radiography service.  The service is provided in conjunction
with another company that obtains the images, and the docs here read
the films for a fee.  To date, the way this works is a portable
radiography unit is transported to the site (nursing home, outpatient
clinic, etc) where an image receptor (called an IP) of a Computed
Radiography (CR) system is exposed.  The IP is returned to our
institution where it is processed using dedicated equipment in a
conventional manner.  The film is then interpreted by a radiologist.

I was approached with the following question: can the device which is
used to extract the information from the exposed IP (a CR reader) be
placed into some type of vehicle and be used in a mobile environment.
In this setting, the CR reader and the radiographic equipment would be
transported toq the site.  At the site, the IP would be exposed and
processed by the CR reader, with the resulting digital image data set
saved on a associated computer system.  The data would then be
transmitted back to the department for processing.  The hope is to
reduce delays, etc, etc.

The question that I have for this group is, provided all of the other
issues are worked out, how to get the data from the van back to the
department in an efficient and cost effective manner?  What options
are available?  I have heard a little about cellular modems, but
understand that they have very limited bandwidth.  For this
application, each image will be approx 8MByte, with 3-5 images / hour.

Thank you for your help.


Douglas M. Tucker, Ph.D.
Assistant Professor, Department of Radiology
UAB Hospital and Clinics
619 S. 19th Street
Birmingham, AL  35213
E-Mail: dtucker@rad.uab.edu
Phone: (205) 934-1905 FAX: (205) 975-4679

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

From: fitzgeraldj@netc.ie
Subject: Irish and European ISDN Approvals
Date: 24 Apr 1994 06:21:22 -0500
Organization: UTexas Mail-to-News Gateway


The Department of Transport, Energy and Communications (the Irish
Telecommunications Approvals Body) has recently introduced its interim
regulations for the approval of ISDN terminal equipment in Ireland.
These regulations will remain until the ISDN Common Technical
Regulations (CTRs) are available, which it now appears may not be for
some time.

The Department has nominated the National Electronics Test Centre
(NETC), Forbairt (the Irish Development Agency), to evaluate all
approval applications on its behalf. The Centre's application for
accreditation has been recommended by the Irish Certification and
Laboratory Accreditation Board (ICLAB). Companies wishing to sell
their ISDN products in Ireland may apply directly to NETC. In cases
where products have already been tested and approved in other
countries, NETC will evaluate the relevant documentation and will
advise on any further testing which may be required to meet the Irish
regulations. NETC will also issue a short report to the Department. A
fee will be charged for this service.  Applicants with partial foreign
approvals may also have the balance of work carried out by NETC.

The Centre can provide testing to the new Irish requirements,
including NET 3, the European mandatory requirement for Basic Access
and to NET 5, the European mandatory requirement for Primary Rate
Access. The Centre can also carry out full conformance tests (i.e.
beyond the limited NET tests) for both of these services and for ISDN
terminal adaptors.

Because the Centre has the only Irish laboratory listed in the EC
Official Journal for safety testing in accordance with the Low Voltage
Directive, NETC can carry out the necessary safety testing, to
harmonised European and international standards, on new telecommuni-
cations products.

American companies who wish to have their ISDN products approved to
European standards or their existing approvals evaluated for
connection to the Irish ISDN should contact me.


Jackie FitzGerald    Internet Mail : fitzgeraldj@netc.ie.
National Electronics Test Centre
Forbairt  Glasnevin  Dublin 9  Ireland
Tel: 353 1 8370101   Fax: 353 1 8370705 / 8379620

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

From: maillet@DELPHI.COM
Subject: 16 Mbps Modem for Real?
Date: Sat, 23 Apr 94 21:59:14 -0500
Organization: Delphi (info@delphi.com email, 800-695-4005 voice)


 From the May, 1994 issue of {Computer Shopper}
Trends & Technology Pg-61
"Small Firm Delivers Big on Digital Signal Compression"

Has anyone heard of a small company called Digital Compression
Technology (DCT)?  It claims it can move 16 Mbps of various kinds of
data down a regular telephone line (yes, that's 16 MEGABITS per
SECOND).

"DCT technology lets telephone wire simultaneously carry four 1.5 Mbps
VCR quality video channels; two broadcast quality 3 Mbps video
channels; two 1.5 Mbps two-way interactive videoconferencing channels;
and ten other channels dedficated to a mix of videophone, fax, and
program selection channels."
 
Is this for real or is DCT a couple of engineering students with some
vaporware, a fax machine, and a gift for self-promotion?


CYBERETSU BBS    CONNECTING THE WORLD

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

From: MVM@cup.portal.com
Subject: MCI Mail Adds Services Available via Internet
Date: Sat, 23 Apr 94 21:22:05 PDT


(Found on the "MCI Mail News" bulletin board:)

Date:     Wed Apr 20, 1994 10:30 pm  CDT 
Subject:  MCI TO OFFER FAX, TELEX AND PAPER BASED MCI MAIL DELIVERY

           MCI TO OFFER FAX, TELEX AND PAPER-BASED
         MCI MAIL DELIVERY SERVICES TO INTERNET USERS


     WASHINGTON, D.C., April 18, 1994 -- To meet the growing demand of
the some 20 million Internet users for fast, reliable messaging
options, MCI Communications Corporation announced it will provide free
subscription to its electronic MCI Mail value-added delivery services.

     The service expansion, announced at the Electronic Messaging
Association's (EMA) 1994 trade show in Anaheim, enables Internet users
to send important electronic mail messages to any valid facsimile,
telex, postal or courier address worldwide, 24 hours a day, 7 days a
week, at standard MCI Mail rates.  The company plans to make these
delivery options available in June to Internet users who register with
MCI Mail.

    "The demand for more sophisticated messaging and information
services will grow exponentially as businesses and consumers continue
to take advantage of the capabilities developed through the convergence 
of multimedia, computers and telecommunications," said Marilyn
Bardsley, MCI's vice president for messaging and information services.

     "Our efforts to expand MCI Mail services to the Internet user
community is part of our overall networkMCI vision to harness
technologies and turn them into real-world communications tools," said
Bardsley.

     While Internet users have been able to exchange electronic mail
messages and binary files with MCI Mail users since 1989, they did not
have access to message delivery options or enhanced message handling
capabilities commonly used by MCI Mail customers for years.  Internet
users must either go outside the Internet to send messages via other
delivery methods or obtain them through specialized commercial
providers on the Internet whose service offerings may be limited by
available delivery choices and geographic coverage.

     With these new capabilities, Internet users can take advantage of
MCI's full range of service options and enhanced features which
include electronic message transfer to letterhead and use of signature
graphics; image transmission via fax; alternate addressing when
sending a fax; and automatic retry for fax and telex.

     According to Vinton G. Cerf, MCI's senior vice president for data
architecture and president of the Internet Society, "the Internet
community has always used electronic mail to communicate with associates.
 
    "Now, with the growth in the commercial Internet, we anticipate
these millions of users will need access to reliable messaging
services to supplement their e-mail correspondence.  MCI Mail's global
service is equipped to meet those needs," said Cerf.

     When the new options are available, Internet users will be able
to register electronically for the services.  Registration entitles
users to have their mailbox information included in MCI Mail's online
directory, as well as access to MCI Mail customer support.

     The cost to use these value-added services will be at the
standard MCI Mail rates for fax, telex, postal and courier delivery.
For further information and registration, Internet users should send
an e-mail message to:

      MCI-info-request@gatekeeper.mcimail.com and type `help'
      as the text of the message.

     MCI also will be providing information about the new service at
the EMA trade show in the MCI exhibit booth #210.

     MCI Communications Corporation headquartered in Washington, D.C.,
offers a full range of domestic and global telecommunications services
through one of the world's largest state-of-the-art networks.  The
company, with 1993 revenue of nearly $12 billion, is the second
largest long distance provider in the U.S. and has more than 65
offices in 60 countries and places.

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

From: doreen@iti.gov.sg (Doreen from NCS)
Subject: Job Opportunities in ITI, NCB, Singapore
Organization: National Computer Board, Singapore
Date: Sun, 24 Apr 1994 06:45:43 GMT


     BE PART OF SINGAPORE'S VISION TO CREATE AN INTELLIGENT ISLAND

The Information Technology Institute (ITI), the applied R&D arm of the
National Computer Board, seeks to accomplish its mission of creating
and deploying advanced IT innovations by working with local and
international companies in joint ventures and projects.  Our R&D
efforts are industry-driven.  We focus on innovations which would
significantly improve our partners' competitive advantage, and
products that have commercial potential.  We invite applications from
suitably qualified candidates for the position of:
 
      * Senior R&D Engineer *

You are expected to set directions and provide technical leadership to
the communication product development group.  In addition, you should
initate and lead projects as well as provide consultancy to project
teams.

- Degree in Computer Science or Electronic Engineering;
- At least 5 years' substantial experience in data communications or
 networking preferably with industry;
- Creative, self-motivated and good interpersonal skills;

If you are keen to pursue a career with us and possess the relevant
qualifica- tions and experience, please write to us with a comprehensive 
resume stating details of your qualifications, current and expected
salary, contact number and internet account number.  Please send these
to:

                Dr Francis Yeoh
         Director, Research & Development
         Information Technology Institute
         71 Science Park Drive
         Singapore 0511

Alternatively, you may wish to respond through internet account: 

         doreen@iti.gov.sg

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

From: tom@interaccess.com (Tom Simonds)
Subject: Channel Bank Recommendations Wanted
Date: 23 Apr 1994 19:45:18 -0500
Organization: The second InterAccess INN server


Our company is looking to buy channel banks.  Can anyone recommend any
brands/manufacturers?  If so, phone numbers or city/state would be
extremely helpful.

Please email to tom@interaccess.com


Tom Simonds  tom@interaccess.com   708-671-3469

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

Date: Sat, 23 Apr 94 13:20 EST
From: Fred Bauer <FBAUER+aROCKVILLE%Rockville@mcimail.com>
Subject: IDB/Peoples Telephone Plan Merger


I think that the readers of the Digest may be interested in the
latest merger in the telecom industry ...

Fred Bauer
   
IDB COMMUNICATIONS SIGNS LETTER OF INTENT TO MERGE WITH PEOPLES
TELEPHONE COMPANY  

IDB EXPECTS COMBINATION TO BOOST EARNINGS  

LOS ANGELES, CA and MIAMI, FL - APRIL 21, 1994 -- IDB Communications
Group, Inc. (NASDAQ:IDBX) and Peoples Telephone Company, Inc.
(NASDAQ:PTEL) today jointly announced they have signed a letter of
intent under which IDB will merge with Peoples.  Shareholders of the
Miami-based Peoples will receive 1.1 shares of IDB Communications
common stock for each share of Peoples common stock, subject to
possible adjustment based upon IDB's stock price prior to closing.  As
of March 31, 1994, Peoples Telephone has approximately 15.8 million
common shares outstanding and approximately 3.1 million common shares
issuable upon the exercise of outstanding options and warrants at an
aggregate price of approximately $23 million.  The transaction will be
effected as a pooling of interests, and will not be taxable to current
Peoples shareholders.  IDB Communications expects the merger to boost
its 1994 earnings per share.  Peoples has been in the public pay
telephone business since 1985.  The Company has an installed base of
approximately 50,000 public, inmate and cellular pay telephones
located in 46 states.  During recent years Peoples has leveraged its
industry expertise to expand into related telecommunication businesses
including correctional facility telephones, cellular telephone rentals
and prepaid calling cards.

The proposed acquisition is subject to satisfaction of customary
conditions, including completion of due diligence by both parties,
execution of a definitive agreement, approval by the shareholders of
both companies and certain regulatory filings, and is expected to be
completed by the end of 1994.

Jeffrey P. Sudikoff, chairman and CEO of IDB, stated, "One of our key
goals in 1994 is to expand IDB's presence in the domestic telecommunica-
tions marketplace.  The merger with Peoples will accomplish this
objective.  Jeff Hanft and his team have built Peoples into the
largest independent operator of public pay telephones in the United
States.  Combined with the company's related telecommunications
services, Peoples currently generates more than 300 million minutes of
long distance traffic a year.  As a result, Peoples and IDB will have
the foundation for a highly profitable domestic public switched
network."

"We fully expect this combination to have a positive impact on 1994
IDB earnings per share.  By applying many of the principles we have
successfully used in acquisitions during the past few years we expect
to significantly enhance the operating strengths of Peoples while
vastly expanding our domestic marketing capabilities," Mr. Sudikoff
added.

Jeff Hanft, CEO of Peoples stated, "IDB has emerged as the most
innovative, rapidly growing telecommunications company in the world.
We at Peoples share many of the same visions and strategic approaches
of IDB's management team.  We look forward to working with IDB and
believe that all of our customers, employees and shareholders will
benefit from the combination of the two companies."

IDB Communications Group, Inc. is a global telecommunications company
that operates a domestic and international communications network
providing its customers with international private line and long
distance telephone services, radio and television transmission
services, facsimile and data connections, mobile satellite
communications capabilities and the design and integration of
satellite networks worldwide.

Peoples Telephone Company, Inc., one of the nation's leading public
communications companies, owns and operates approximately 50,000
public, inmate and cellular pay telephones in 46 states.  For the year
ended December 31, 1993, the Company reported revenues of $121.8
million, an increase of 63%, net income of $5.3 million, an increase
of 64%, and cash flow from operations of $27.5 million, an increase of
54%, all as compared to the year ended December 31, 1992.

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

Date: Sat, 23 Apr 1994 20:05:58 EST
From: Ralph E. Todd <rtodd@mason1.gmu.edu>
Subject: Remote Interactive Classroom Instruction - How Far We've Come!


Greetings!

I am the graduate student in the Telecommunications program at George
Mason University (GMU) who submitted the request for information on
conferencing on the Internet in early March.  On behalf of my class
project group, which formed to implement the solution that evolved
from the many thoughtful responses I received, I wanted to inform you
of our progress.

You may recall that the immediate application is interactive televised
graduate instruction.  The prototype course, "Taming the Electronic
Frontier," is taught by Dr. Brad Cox and televised on regional cable
television.  Most of the students, including an entire section, are in
the TV audience.  These tele-students had no way of participating in
the interactive dimension of the course.

Subsequent to publication of my request, I received a consensus
response among TELECOM Digest subscribers that Internet Relay Chat
(IRC) would provide an effective solution.  With the combined
dedication and effort of my fellow group members Umar Badeges, Leesia
Huffner, Altaf Khan, and Cynthia Roubie, an extremely supportive
computer system manager, and an enthusiastic and helpful television
producer, Remote Interactive Classroom Instruction (RICI) made its
debut at George Mason University on April 19. Students in the TV
audience used their PCs at home to connect to the university Internet
host computer, and join in an IRC conference with Dr. Cox during his
lecture.  The "mesg n" command was used in advance of initiating IRC
to block distracting messages, and the "mode * +k" command, used by
the professor when opening the channel, kept out intruders; we had
several interruptions by "bots" while conducting group meetings on
IRC.  Our first RICI session was a resounding success!

We have created student and instructor Guides to Using RICI, which
along with a Guide to Future Enhancements will be available on the GMU
Internet Gopher.  Identified future enhancements include a switch to
display IRC text on-air, audio conferencing including voice-delay, and
videoconferencing to regional libraries using local cable television
channels.  We welcome questions and comments.


Ralph Todd             > rtodd@mason1.gmu.edu            (703) 658-9668
George Mason University                      Telecommunications Program


[TELECOM Digest Editor's Note: What a really great report! I was one of
many people a few years ago when IRC was first developed and put into use
who wondered what real benefit it would have to the Internet. It has been
often-times just a huge waste of network resources, but your report today
shows there is a lot of good it can do.   PAT]

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

From: idddsb@iddss1.iddis.com (Dean Banfield)
Subject: ISDN Bridge Advice Please
Date: 24 Apr 1994 02:36:04 GMT
Organization: IDD Information Services


Hi,

We have a 10baseT Ethernet lan and would like an outlier individual to
have access on a hardwired basis.  ISDN sounds great, but I have no
idea what's required here.

You take the 64kpbs 'B' channels and then using a 'bridge?' you
convert the serial data to 10baseT?  Who makes bridges?  At what
prices?  I assume higher price translates into higher performance.
Any info appreciated.  Thanks.


Dean Banfield  IDD/Information Svcs
               90 Grove St
               Ridgefield CT 06877

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

From: rtodt@relay.nswc.navy.mil (Rodney Todt)
Subject: DISN Information Request
Organization: NAVAL SURFACE WARFARE CENTER
Date: Sun, 24 Apr 1994 03:12:57 GMT


 Can anyone in this group provide me with a pointer to online
information about DISN.  I am specifically looking for a map and how
to get connected information. Thanks.


Rodney Todt   DDN Mail:  rtodt@relay.nswc.navy.mil
Naval Surface Warfare Center Phone:     (703) 663-4146
Dahlgren Division  DSN:             249-4146
Code E81, Networks Branch FAX:       (703) 663-1952
Dahlgren, Virginia  22448-5000  

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

Date: Sun, 24 Apr 1994 12:39:59 GMT
From: T.I.Boogaart@research.ptt.nl (Boogaart T.I.)
Subject: Quality of Long Distance Telephone Lines
Reply-To: T.I.Boogaart@research.ptt.nl
Organization: PTT Research, The Netherlands


I would like to know if anyone has conducted research on the quality
of long distance telephone lines. With "Quality" I mean the amount of
noise and echo (e.g. signal noise ratio). In particular, I want to
know if it is at all feasible to perform speech recognition / speaker
verification over long distance lines.

The focus is on the quality of lines to Europe, but any information on
the subject (references, pointers, hints) is welcome.

Please send e-mail to me directly, as I don't subscribe to this newsgroup.
I'll summarize if there is enough interest.


Thanks in advance,

Tineke Boogaart <T.I.Boogaart@research.ptt.nl>

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

From: cm@nwu.edu (Chris Michael)
Subject: x.25 networks
Date: 23 Apr 94 17:20:59 GMT
Organization: Northwestern University, Evanston, IL  USA
Reply-To: cm@nwu.edu (Chris Michael)


I'm looking for data connectivity between Chicago and Milan Italy.
I'm guessing that X.25 will be cheaper than a leased line, but I'm
having a heck of a time finding anyone to quote me a price.  Does
anyone have any thoughts about relative pricing?  I assume Telenet and
Tymnet are still around.  Anyone know where?


Thanks,

christopher michael, george s. may international, 708-825-8806 x 395

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

End of TELECOM Digest V14 #181
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