TELECOM Digest     Thu, 13 Oct 94 13:34:00 CDT    Volume 14 : Issue
395
 
Inside This Issue:                           Editor: Patrick A. 
Townson
 
     Re: Frame Relay vs. ISDN vs. T1 vs. ???? (Lars Poulsen)
     Re: Frame Relay vs. ISDN vs. T1 vs. ???? (lawrim@inforamp.net)
     Re: Frame Relay vs. ISDN vs. T1 vs. ???? (Greg Ruml)
     SONET/ATM, Video Compression Short Courses -- UC Berkeley (Harvey 
Stern)
     Re: 25 Years of Call Waiting (Danny Burstein)
     Re: GSM SIM Card: Different? (Stephen Ermann)
     BCH 3/5 Error Detection Modules (Allan Rypka)
     Re: V.34 From ITU-T (John E. Lundgren)
     Re: V.34 From ITU-T (Ken Krechmer)
     Dialstrings on DMS-100 (George L. Sicherman)
     Re: UDI vs RDI in ISDN (Kevin Paul Herbert)
     Re: Need Amp to Boost DTMF Strength (Les Reeves)
     Re: OSI OM-Related Tools (Grover McCoury)
 
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From: lars@spectrum.RNS.COM (Lars Poulsen)
Subject: Re: Frame Relay vs. ISDN vs. T1 vs. ????
Date: 13 Oct 1994 10:35:37 -0700
Organization: Rockwell Network Systems
 
 
A couple of recent contributions indicate that there is some confusion
about contemporary data communications options.
 
spelegan@csc.com wrote:
 
> We have a commercial customer who's asked us to setup a BBS system 
for
> them.  They've asked us to recommend a telecom option for them to
> use that best suits their needs.  They'd like to start out with 8
> lines going into the BBS with the ability to move up to 16, 24, etc.
> They'd like their customers to have one 800 number to call to reach
> this BBS, no matter where they are in the US.  Their customers will
> have off-the-shelf modems, ranging from 1200-14.4 baud.
 
The requirement here is for an economical way to accept POTS calls for
modem traffic. This means that X.25 service, Frame Relay, ISDN etc are
all outside of the scope of this query. That will not prevent me from
getting back to them at the end, though.
 
The simple, easy solution is to get 8 lines (in a hunt group) from
your local exchange carrier, and arrange for an 800-number from a
competitively priced long distance company which forwards to these
lines.
 
If you have really high volume, you may save a couple of cents per
minute bypassing the local carrier and installing a T1 line directly
to the long distance carrier's POP, but then you will need a channel
bank to split the lines back out to individual lines before they go
into your modems.
 
Any modems installed today should be 28800 bps models; either V.FC or
V.34. V.34 may still be hard to get at a reasonable price, though.
 
And now a word about ISDN:
 
In article <telecom14.390.3@eecs.nwu.edu> misha@panix.com (Michael
Gray) writes:
 
> ISDN connections would allow you to connect to BOTH customers with
> POTS (Plain Old Telephone Services) services and with ISDN services,
> however you need separate ISDN modems and 28Kbs modems, special
> equipment to hook the 28.8Kbs modems to the ISDN lines.
 
In Europe, it is not uncommon to find ISDN adapters that include a
V.32bis (14400 bps) modem, so that they will accept connections using
either V.32bis (from customers with ordinary phone lins and ordinary
modems) or V.110 asynchronous rate adaptation (from customers with
compatible ISDN adapters). In the US, these dual-mode adapters have
not been very popular. If they could be had, the cost would be nearly
USD 2000 per port. My conclusion is that it is not worth it yet, and
when you do gear up for ISDN, you will probably be better off with
separate ports / separate lines for ISDN access..
 
Sp> I'm even more cloudy on Frame Relay.  Can I have one 800 number 
with
Sp> Frame Relay?  Do you need a special terminal/modem to dial into a
Sp> frame relay network?  How does it compare to T1?  vs. T1 cost?  
vs.
Sp> T1 reliability?  Please correct any assumptions that I've made T1,
Sp> ISDN, and Frame Relay.
 
Frame relay is sort of similar to X.25, sort of similar to leased 56
kbps lines. The physical jack is a leased 56 kbps (or 384 kbps) line
into the carrier's Frame Relay switch. This line is shared by
connections to multiple, presubscribed locations. So if you have 4
sites, you can have them all talk to each other by giving each of them
a leased line into the telephone company's FR switch, instead of
needing 6 lines to connect them all. The equipment at all locations
must understand the FR multiplexing protocol.
 
Finally:
 
You should give serious consideration to putting such a BBS on the
Internet.
 
 
Lars Poulsen   Internet E-mail: lars@CMC.COM
Rockwell Network Systems Phone:        +1-805-562-3158
7402 Hollister Avenue   Telefax:      +1-805-968-8256
Santa Barbara, CA 93105   Internets: designed and built while you wait
 
------------------------------
 
From: lawrim@inforamp.net
Subject: Re: Frame Relay vs. ISDN vs. T1 vs. ????
Date: 13 Oct 1994 01:10:26 -0400
Organization: InfoRamp, Toronto Ont. (416) 363-9100
Reply-To: lawrim@inforamp.net
 
 
T1 service is getting cheaper by the month.I have seen prices here in
Toronto range from $750.00 to $1500.00 (Canadian) ISDN is offered by
Bell Canada very cheap.There Megalink service for example can be had
for $78.00/mo.This isfor basic services providing what is called
2B+D,2-64k channels and one 16k channel.
 
Frame Relay is a high speed packet switching network.Each packet of
data carries a much higher payload then X.25 packets.You usually pay a
monthly port charge and usage based on a committed information rate
(CIR).Access is 56k and the CIR is a portion or all of it.Frame relay
applications are generally used in a multipoint situation.  Other
options could be centrex data and dial-up X.25.A competant data
provider should have no problem costing out the various applications
mentioned.
 
 
Good Luck,
 
Lawrie
 
------------------------------
 
From: gruml@buscomm.mts.mb.ca (Greg Ruml)
Subject: Re: Frame Relay vs. ISDN vs. T1 vs. ????
Date: Tue, 11 Oct 1994 15:49:20 -0400
Organization: MTS
 
 
For your application you are suggesting 800 service. 800 service is a
voice service by definition where the subscriber pays the long
distance charges.
 
Frame relay is not your answer. I have heard that some of the carriers
will have dial access to frame relay, but I don't believe it is
available yet.  Frame relay is a dedicated data service at speeds of
56,000 bps or 64,000 bps (and multiples thereof).
 
Frame relay requires a device called a FRAD. This device packetizes
the data into frames, putting a header and trailer around a block of
data. The FRAD also checks the data when it is sent and then when it
arrives to ensure the data is without errors. These FRADs required
cost $1000 and up.
 
Your answer really depends on what equipment your client has today. If
they have a PBX with T1 ISDN PRI capability, it may make sense to put
these lines on ISDN. ISDN is a voice and data service that is a
digital signal and therefore you get a higher grade of service. ISDN,
because it is digital, is less susceptible to interference from
traditional noise sources (ie. motors, signal induction from other
cables, etc.).
 
If they just have an analog key system today it may make sense just to
keep adding standard dial-up lines.
 
Hope this helps.
 
 
Greg Ruml
 
------------------------------
 
From: southbay@garnet.berkeley.edu
Subject: SONET/ATM, Video Compression Short Courses -- UC Berkeley
Date: 12 Oct 1994 17:06:17 GMT
Organization: University of California, Berkeley
 
 
U.C. Berkeley Continuing Education in Engineering Announces 3 Short
Courses on Broadband Communications, and Video Compression
 
 
SONET/ATM-BASED BROADBAND NETWORKS: Systems, Architectures and Designs
(October 19-21, 1994)
 
It is widely accepted that future broadband networks will be based on
the SONET (Synchronous Optical Network) standards and the ATM
(Asynchronous transfer Mode) technique.  This course is an in-depth
examination of the fundamental concepts and the implementation issues
for development of future high-speed networks.  Topics include:
Broadband ISDN Transfer Protocol, high speed computer/network
interface (HiPPI), ATM switch architectures, ATM network
congestion/flow control, VLSI designs in SONET/ATM networks.  This
course is intended for engineers who are currently active or
anticipate future involvement in this field.
 
Lecturer: H. Jonathan Chao, Ph.D., Associate Professor, Brooklyn
Polytechnic University.  Dr. Chao holds more than a dozen patents and
has authored over 40 technical publications in the areas of ATM
switches, high-speed computer communications, and congestion/flow
control in ATM networks.
 
GIGABIT/SEC DATA AND COMMUNICATIONS NETWORKS: Internetworking,
Signaling and Network Management (October 17-18, 1994)
 
This short course aims to provide a general understanding of the
key issues needed to design and implement gigabit local and wide
area networks.  The topics are designed to compliment those
covered in the SONET/ATM-Based Broadband Networks course (above).
 
Topics include: technology drivers, data protocols, signaling, network
management, internetworking and applications.  Specific issues
addressed include TCP/IP on ATM networks, design of high performance
network interfaces, internetworking ATM networks with other network
types, and techniques for transporting video over gigabit networks.
This course is intended for engineers who are currently active or
anticipate future involvement in this field.
 
Lecturer: William E. Stephens, Ph.D., Director, High-Speed Switching
and Storage Technology Group, Applied Research, Bellcore.  Dr.
Stephens has over 40 publications and one patent in the field of
optical communications.  He has served on several technical program
committees, including IEEE GLOBECOM and the IEEE Electronic Components
Technology Conference, and has served as Guest Editor for the IEEE
Journal on Selected Areas in Communications.
 
 
VIDEO COMPRESSION AND VISUAL COMMUNICATION (October 13-14, 1994)
 
Video Compression and Visual Communication is a rapidly evolving
multidisciplinary field focussing on the development of technologies
and standards for efficient storage and transmission of video signals.
It covers areas of video compression algorithms, VLSI technology,
standards, and high-speed digital networks.  It is a critical enabling
technology for the emerging information superhighway for offering
various video services.  In this course, we will fully treat video
compression algorithms and standards, and discuss the issues related
to the transport of video over various networks.
 
Lecturers: Ming-Ting Sun, Ph.D, is director of Video Signal Processing
Research, Bellcore.  Dr. Sun has published numerous technical papers,
holds four patents, developed IEEE Std 1180- 1990, was awarded the
Best Paper Award for IEEE Transactions Video Technology in 1993 (with
Tzou), and an award for excellence in standards development from the
IEEE Standards Board in 1991.  He is currently the express letter
editor, IEEE Transaction on Circuits and Systems for Video Technology
(CSVT), and associate editor, IEEE Transactions of CSVT.  He was
chairman and now serves as secretary of the IEEE CAS Technical
committee on Visual Signal Processing and Communications.
 
Kou-Hu Tzou, Ph.D., is manager of the Image Processing Department,
COMSAT Laboratories.  Dr Tzou won the Best Paper Award for IEEE
Transactions Video Technology in 1993 (with Sun).  He holds 6 patents,
has served as an associate editor for IEEE Transactions on Circuits
and Systems, is currently associate editor for IEEE Transactions on
Circuits and Systems for Video Technology, and served as a guest
editor for Optical Engineering Journal special issues on Visual
Communications and Image Processing in 1989, 91, and 93.  He is the
committee chair of the Visual Signal Processing and Communication
Technical committee, IEEE Circuits and Systems Society.
 
 
For more information (complete course descriptions, outlines,
instructor bios, etc.) contact:
 
Harvey Stern
U.C. Berkeley Extension/Southbay
800 El Camino Real Ste. 150
Menlo Park, CA 94025
Tel: (415) 323-8141   Fax: (415) 323-1438
 
------------------------------
 
From: dannyb@panix.com (danny burstein)
Subject: Re: 25 Years of Call Waiting
Date: 13 Oct 1994 00:19:44 -0400
Organization: mostly unorganized
 
 
In <telecom14.394.2@eecs.nwu.edu> marya@titan.ucs.umass.edu (jwm)
writes:
 
<snip> advert from Nynex about call waiting being in existence for
twenty-five years <snip>
 
> Discover why Call Waiting has been our most popular service for more
> than 25 years.
 
> really deployed as early as 1969?  What switches at the time 
supported
> them?  Did anyone out there have Call Waiting from New England
> Telephone and Telegraph Co. in 1969?
 
I was one of the first public customers for call waiting in NYC. In
fact, I picked up call waiting, call forwarding, and three way calling
as soon as I could in mid 1975.
 
Back in those days I used to call New York Telephone's semi-internal
Newswire which had all sorts of interesting, sometimes technical,
sometimes amusing, material in it. (It also had the AT&T stock market
price as well as the weather report, and it was a free call...)
 
Anyway, they mentioned in the report that their internal tests had 
just
been finished and it was being rolled out to the public. So the 
initial
NYC public offering was in 1973/early 1974.
 
I had to wait a bit until I left campus residential housing before
I could get my own phone, and when I did, I got the features 
installed.
(BTW this had the side effect of leaving me with one of the older
switches in NYC - i.e., since it was a 'new' one in 1974, it's not 
being
replaced anytime soon ...)
 
Back then they were called CSS for Custom (something) Sevices, and
trying to get it ordered for my phone line was one of my early
experiences in telco frustration. But I did get it.
 
Back in those days, by the way, the codes used for implementing
forwarding were different than the ones used today (I -think- it was
'1191' to start it and '1193' to end).
 
The call forwarding was the more interesting of the features. Back
then I would forward the number to the (last hunt line) of where I was
working.  So if a call came in on that line, we all knew it was
(probably) a private call for one of us and answered appropriately.
(After I had the service for a few weeks, the other people also got
call forwarding on their lines).
 
Keep in mind, by the way, that in 1975 telephone answering machines
were a lot clunkier and more expensive, and remote message retrieval
was not readily available. And a unit with remote message changing
cost me about six-hundred dollars a few years later. Yes, really, and
that's when $600 was real money ...
 
So it's -just- possible that it was available to a few select areas on
the early #1-ESS machines in 1969, but certainly not on a widespread
basis.
 
Oh, another point: In those days telco equipment was amortized over a
-looonnngggg- period, so a central office would not be replaced simply
becuase something newer and better was out there. In fact, it's only
in the few years that the last mechanical exchanges in the NYC area
were retired.
 
O, yet one more point: The first area of NYC to get fully
computerized
equipment was the lower east side/Gramercy Park neighborhood. You see,
New York Tel had a bit of a fire at their 13th street and 2nd avenue
office which put Hinsdale to shame. In the space of a month they had
completely replaced all the equipment in teh building with what were
then brand-new ESS's.
 
 
danny burstein   dannyb@panix.com (or dburstein@mcimail.com)
 
 
[TELECOM Digest Editor's Note: I don't think the New York fire in the
early 1970's was as severe as Hinsdale, but I guess that's a matter of
each person's judgment. Hinsdale certainly handled a wider scope of
services and geographical territory than the office in Manhattan. You
are correct about the 1191 and 1193 codes. 11 (pronounced 'eleven' in
this application) was to be used by people with older touch tone pads
that did not include the * and # buttons. You may recall the original
touch tone pads only had ten buttons with the bottom row only having
the zero/operator key and nothing on either side of it. So you turned
on forwarding with 1191 or *91 and turned it off with 1193 or *93. I
was one of the first subscribers here in 1973 or 1974, I forget which.
The interesting thing about the original call forwarding here was that
chain forwarding would not work at all. A would forward to B and B 
would
forward to C for example ... but calls to A absolutely stopped at B
regardless of what B was doing with calls directly sent to him. The
idea was B is entitled to forward to C but B has no authority to 
assume
A is willing to have his calls go to C. Apparently the switch was able
to tell when a call hit B from whence it came, and respond 
accordingly.
If you were actually looking for B, you were sent on to C as 
instructed
but if you were looking for A and got sent to B in the process you 
stopped
there.
 
Also, the early version of call waiting had no provision to suspend 
the
service for those calls you did not want interuppted. If you had call
waiting on the line you were stuck with it. Of course modems were 
pretty
rare in the middle 1970's so it was not a big problem with data as it
would be today if suspend call waiting (usually *70 before the dialing
string) were not available.   PAT]
 
------------------------------
 
From: 100111.1007@compuserve.com
Date: 13 Oct 94 03:24:30 EDT
Subject: Re: GSM SIM Card: Different?
 
 
>> Is this true? As I understand, with only one SIM card you can use 
any
>> GSM handphone in any country (of course as long as the countries 
have
>> roaming agreement).
 
Well, yes and no: The SIM card exists in two physical formats: large
(credit-card sized) and small (chip sized, 1cm x 1.5cm).  The Motorola
5200 & 7200 use the large card, while most other manufacturers use the
small one in most models to my knowledge.
 
The chip itself seems to be the same, as when I switched from a
Motorola 5200 to a Nokio 2110, I just cut the SIM card to the right
size and inserted it.
 
So to answer your question: you can use any SIM card in any GSM phone,
as long as it has the same form factor.
 
 
Regards,
 
Stephen Ermann    Switzerland
 
------------------------------
 
From: pp000762@interramp.com
Subject: BCH 3/5 Error Detection Modules
Date: Thu, 13 Oct 94 23:04:22 EDT
Organization: PSI Public Usenet Link
 
 
Can anyone provide the name/number of firms producing pre-programmed
off the shelf BCH 3/5 forward error correction modules for use in data
transmission systems?
 
 
Thanks in advance,
 
Allan Rypka   Focused Research
 
------------------------------
 
From: jlundgr@eis.calstate.edu (John E. Lundgren)
Subject: Re: V.34 From ITU-T
Date: 13 Oct 1994 07:50:50 -0700
Organization: California Technology Project of The Calif State Univ
 
 
tannil@tcl.com.hk (Tannil Lam) writes:
 
> Please advice the newest status of V.34 from ITU-T. I hope to know
> whether V.34 has been official approved for modem manufacturers to
> produce their V.34 products or not.
 
I read a post saying that a vote had been taken and it had been 
approved,
and it will be published in late October.
 
 
John Lundgren $$$$$$ jlundgr@eis.calstate.edu $$ jlundgr@ctp.org
jlundgre@rsc.rancho.cc.ca.us $$$$$$ Standard Disclaimers apply.
Rancho Santiago College - 17th St. at Bristol - Santa Ana, CA 92706
 
------------------------------
 
From: krechmer@ix.netcom.com (Ken Krechmer)
Subject: Re: V.34 From ITU-T
Date: 12 Oct 1994 22:20:03 GMT
Organization: Netcom
 
 
In <telecom14.378.3@eecs.nwu.edu> tannil@tcl.com.hk (Tannil Lam) 
writes:
 
> Please advice the newest status of V.34 from ITU-T. I hope to know
> whether V.34 has been official approved for modem manufacturers to
> produce their V.34 products or not.
 
The V.34 and associated V.8 Recommendations are approved. The
ratification cycle ended about two weeks ago.
 
 
Ken Krechmer   Technical Editor
Communications Standards Review
e-mail: kkrechmer@attmail.com
 
------------------------------
 
From: George.L.Sicherman@att.com
Subject: Dialstrings on DMS-100
Organization: AT&T Network Systems
Date: Thu, 13 Oct 1994 14:23:50 GMT
 
 
How does Northern Telecom's Digital Multiplex Switch 100 (DMS-100)
treat fourth-column dialed digits?  The AT&T #5 Electronic Switching
System accepts them pretty much wherever it accepts Star and Box; it
calls them O, S, I, and P, apparently following AutoVON usage.
(Nowadays I think they are more commonly called A, B, C, and D.)
 
The DMS-100 can be programmed to accept "overdecadic" digits from A to
C, or from A to F.  Can anybody explain how (if at all) they 
correspond
to the fourth-column tones?
 
 
Col. G. L. Sicherman    gls@hrcms.ATT.COM
 
------------------------------
 
From: kph@cisco.com (Kevin Paul Herbert)
Subject: Re: UDI vs RDI in ISDN
Date: Thu, 13 Oct 1994 07:46:26 -0700
Organization: Cisco Systems, Ashland, OR
 
 
RDI is a 64K channel on which you are expected to maintain a
particular ones density. This can be used to transmit HDLC data if you
invert the bits; HDLC has a different reason for avoiding 6 one bits
in a row; by inverting this, you can assure that there are never 6
zero bits in a row.
 
I'm not sure if RDI is actually supported anywhere.
 
 
Kevin
 
------------------------------
 
From: lreeves@crl.com (Les Reeves)
Subject: Re: Need Amp to Boost DTMF Strength
Date: 13 Oct 1994 08:41:42 -0700
Organization: CR Labs
 
 
htc (htcink@teleport.com) wrote:
 
> I need an inexpensive in-line amplifier circuit capable of boosting 
dB
> level of DTMF generated from newer ("non-network") telephone sets
> (mfg'd by Panasonic, Sony,...)  Telephone sets connect to a PBX 
board
> (in IBM PC) that causes a slight loss of signal strength.  Usually
> only column 2 (i.e. 2,5,8,0) is too weak.  Any suggestions/help or
> schematics would be greatly appreciated.  fax: (503) 645-3566
 
WATS resellers used the R-TEC (Reliance Comm/Tec) VFR5050 2-Wire to
2-Wire repeater for boosting signals.  The repeater is easy to set up,
and unconditionally stable.  It automatically disables itself when
data carriers of any sort are detected.
 
It is widely available on the secondary market for about $100.  I keep
one connected to my line all the time.  My IVR system is able to get
my DTMF signals under the worst conditions with the help of this
repeater.
 
The VFR 5050 requires a type 400 shelf for mounting.
 
R-TEC (AKA Lorain): (817) 267 3141
 
 
Les     lreeves@crl.com       Atlanta,GA      404.874.7806
 
------------------------------
 
From: gcm@fep50.fns.com (Grover McCoury)
Subject: Re: OSI OM-Related Tools
Date: 13 Oct 1994 07:31:07 GMT
Organization: Fujitsu Network Switching
 
 
In article <telecom14.381.7@eecs.nwu.edu>, andrew lavigne 
<alavigne@bnr.
ca> writes:
 
> I've been looking for information on the availability of OSI Object
> Model Management-related toolkits and compilers (ASN.1/GDMO 
compilers,
> object class inheritance display tools, browsers, etc).
 
> Does anyone know of such tools and/or where I can get more 
information
> on them?
 
DSET Corp. provides a set of tools to handle ASN.1 types in C++. The
toolkit is called "ASN.C++" and includes an ASN.1 compiler among other
tools.
 
DSET Corp.
1011 Rt. 22 West
Bridgewater NJ 08807
(908)526-7500
 
 
Grover C. McCoury III
Fujitsu Network Switching Of America, Inc.
physical: 4403 Bland Road
    Raleigh,    NC   27609
audio: 919-790-3111
electronic: gcm@fns.com
 
------------------------------
 
End of TELECOM Digest V14 #395
****************************
 

