TELECOM Digest     Sat, 18 Dec 93 03:10:00 CST    Volume 13 : Issue 824

Inside This Issue:                        Moderator: Patrick A. Townson

   Updated Summary of T1 Equipment With Modem Banks etc. (Aninda Dasgupta)
   Re: Two Cellphones With Same Number? - Not Permitted (Robert J. Keller)
   Mobilnet - Do They Know This? (Douglas Adams via Aaron L. Dickey)
   Re: PCS Questions (Samir Soliman)
   Re: Wireless LANs (Lynne Gregg)
   Re: Saudi Arabia NANP Area Code (Tony Harminc)

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Date: Fri, 17 Dec 93 14:20:07 EST
From: [email protected]  (Aninda Dasgupta)
Subject: Updated Summary of T1 Equipment With Modem Banks etc.


[This is an updated version of a summary I posted a few weeks back.
This article has more recent information obtained from USRobotics.
Also, it gives a "vanilla" solution using DACS and channel banks.

For those who are not familiar with T1 terms and equipment, there was
a nice article on the TeleTech mailing list by [email protected].
com (Scott Statton N1GAK) on Wed, 15 Dec '93, that explained some of
the T1 terms and equipment.]

A number of people from the net asked me to forward whatever
information I have received regarding equipment needed to connect 24
modems to a T1 line.  Below I have described the main features of
each.  All this information is what I have assimilated from
market-speak and brochures of the vendors.

Summary of my application's needs:

I want to provide two kinds of services to my geographically
distributed salespeople; both services are to be provided from a
workstation-based server.

Service 1: Salesperson dials in from his laptop and on my end I want to
dump some ASCII and graphics messages on his laptop screen
- pretty much like a remote terminal server.

Service 2: Salesperson dials in from a POTS telephone, uses DTMF keys to
choose a service and gets messages played back and/or a fax sent to
a fax machine - very much like voice-mail systems, banks offering
credit card balance information and fax-back systems.

I need the two services to be served off one workstation because the
information accessible via the two services (using modems or telephone
sets) is identical and because I want to aggregate my incoming lines
onto a single T1 so that I can get good LD rates from my LD provider.

Vendors that have products that allow offering such services are
listed below.

1) US Robotics - Total Control WAN Hub
  -----------------------------------

This product is offered as a chassis and various options on cards.
They have a dual-T1 card with drop-insert capabilities, frac. T1
enabled, accepts ANI/DNIS and requires no external CSU.  The DSP-based
quad-modem cards have built-in fax-modem (V.32bis) capabilities, can
access DNIS, can load DNIS-dependent modem configuration, will
(someday) route the data to LAN adapters (instead of RS-232 ports) and
can originate and terminate fax/modem calls.  USR also talks about
making LAN adapter cards (Enet and TR) available in late '94, which
will allow direct connections to a Token-ring or Ethernet LAN. They
will also have a LAN Gateway card that will work in conjunction with
the LAN adapters to route data to/from the quad modems to the LAN.

TCP/IP and X.25 will be initially supported on the Gateway cards, and
Appletalk, etc. will be added later. Any application specific protocol
of your choice can be downloaded onto the Gateway card. This will
allow you to use any home-brewn protocols for transactions, data
exchange, etc. between remote applications.  A terminal server card
will be avialable around mid-'94. Voice cards (with RJ11 output, I
guess) will be available "later '94." USR will also have ISDN PRI,
X.25 and Frame Relay cards that go in the same chassis.  The chassis
and most of the cards are controllable/monitorable using SNMP, either
from a PC (with software available from USR) or from any other SNMP
host on the LAN.  Some of the cards are also controllable via RS-232
dumb terminals.

For more (and perhaps accurate) information, contact
US Robotics at (800) 342-5877.
I spoke with Michael Cashman, Ext. 5636 (Marketing/Sales).
I also spoke with Don Balton - (708) 982-5091 who used to head the group
that designed this product, and Lauri Lentz in Public Relations.


2) Primary Access
  --------------
I found out about Primary Access from, among others, its founder, Jim
Dunn.  They are reachable by email. They seem to have a larger
installed base of their product as compared to the USR product
described above.

This prouduct is also a chassis based system.  The single-T1 card has
drop-insert capabilities, is not capable of frac. T1 (from what I
could gather from their glossies), needs an external CSU (but only for
loop-back testing) and accepts ANI/DNIS. However, the ANI/DNIS is
accessible to a host computer only if you use an X.25 link between the
chassis and the host.  This means, in order to get the ANI/DNIS, you
need to buy an X.25 card for the chassis and an X.25 card and software
for the host.

The dual-modem cards are V.32bis compatible, can do DTMF decoding, can
originate and terminate modem calls, and they promise routing of modem
data to LANs within the next year.  These cards don't seem to be as
feature rich as the USR cards (e.g. on the fly, DNIS-dependent
configuration download, etc.). They offer X.25 cards and Frame Relay
too.  Network management is done using CMIP. All software on the cards
can be downloaded for upgrades.  Voice call support is provided using
their 8-port FXS cards (something that is lacking in the USR offering
at this time).  They have promised Ethernet support in about a year.
They assured me that they can price their products very aggressively.

For more information call:
(619) 536-3000
Fax: (619) 693-8829


3) Dialogic
  --------
This is a all-in-a-PC solution.  Dialogic offers a T1 interface card
for the IBM PC bus. This card provides access to ANI/DNIS, has
drop-insert capabilities and requires an external CSU for loop-back
testing.  They have various versions of the T1 card, offering various
options for the number of T1 ports. Also offered is a PC-based
four-channel Voice card that does DSP-based call processing. Combined
with Dialogic's voice-processing software (PCM encode/decode API) and
DTMF recognition capabilities, this card provides an excellent way to
implement voice-based services.  Dialogic also offers fax boards that
will allow you to send out faxes from the PC.  The PC, equipped with a
LAN adapter card can, via the application software route all data to a
network.  I am not aware of network monitoring features (SNMP or
CMIP). Also missing is any V.32bis modem capabilties. One attraction
of going the Dialogic way is the elimination of any cabling which is
needed to connect the USR or Primary Access products to any host
system (e.g. RS-232, twisted-pair etc.).  All the cards use Dialogic's
PEB bus for internal data transfers.

For more information call Dialogic Sales and Technical Support:
(201) 334-1268.


4) IBM's CallPath Line of Products:
  -------------------------------
IBM offers a uniform API to interface to phone systems, independent of
the the PBX vendor and the host system platform.  e.g. one could use
the same programs to implement CallPath-based applications on MVS,
AS/400, OS/2 and AIX based systems and interface to PBXs from Rolm,
NT, etc.  One requirement is the PS/2 based CallPath SwitchServer/2,
which seems to be a system that has hard-wired links to the PBX and
sits on the LAN and serves all requests for operations from the
CallPath host. The host to SwitchServer link is supported using SNA
LU6.2 (yuk!!). They support DID, DNIS, CLID, ANI etc. and have T1
boards for the RS/6000 (I am not aware if they have boards for the
PS/2 and mid to main frame systems, but I assume they do).  Although
an interesting product with a seemingly rich API to perform all kinds
of call routing etc, the main drag is the PS/2 requirement to
interface to a PBX (what if I don't have a PBX?)

For more information call:
(800) IBM-CALL  and ask for information on CallPath line of products.


A Vanilla Solution using DACS, Channel Banks and CSU/DSUs

An alternative to all the above solutions, and perhaps much more messy
(in terms of writing purchase orders and cabling), is to use a CSU box
to terminate the T1 span. Then, use a DACS+Channel Bank to do the
splitting of the lines into modem and voice calls.  However, I am not
sure how one would use two 800 numbers -- one for modem calls and one
for voice, and somehow have the DACS recognize the DNIS and split them
accordingly. Do they make DACS or Channel Banks that will use DNIS to
split the DSO channels? (I bet they do.)

After the Channel Bank, the modem lines would have to be fed into
v.32bis modems. This might create a nasty cable spaghetti between the
Channel Bank and the modems.  Besides, buying and managing 24 or 48
modems is expensive, right?  Then of course there is the cabling from
the modems to the host's serial ports.  I have seen a Wireless RS-232
box that transmits to 500 ft. But I don't know how 24 of them would
perform sitting next to one another.  The advantage of this solution
is that you can buy used equipment for cheap (there are plenty of used
telco equipment vendors) and get something up and running.

[The following sources were mentioned in an article by
[email protected] (Scott Statton N1GAK)]:
Channel Banks: Newbridge, Wescom
DACS: Fredericks' Engineering
CSU/DSU: Kentronics, AT&T etc.

Summary and Wish List:

The Primary Access and USR offerings both look attractive.

I wish Primary Access delivered ANI/DNIS without X.25.

I wish both USR and Primary Access had LAN adapters for their chassis
so that I wouldn't need to run 24 RS-232 cables from the modem cards
to my workstation.  (Getting a workstation equipped with 24 serial
ports is quite difficult.)

The Dialogic product can be neatly packaged in a PC, but I don't trust
a PC to do my important call processing and service providing
functions.  And Dialogic doesn't provide V.32bis modem-banks in their
PC solutions.

Finally, I wish the IBM product didn't need a PBX and a PS/2 to
interface to it.

Disclaimer:
----------
I DO NOT GUARANTEE the accuracy of any of this information.  As I
said, this is what I have understood or guessed from whatever
information I was able to gather directly from the vendors. I might
have misunderstood some deficiencies, or unknowingly embellished some
features.  If so, that was unintentional.  If anybody familiar with
these products finds any inaccuracies, I'd appreciate being told about
it.  If anybody knows of any other such products, I would like to hear
about them too.

Thanks to all those who responded to my queries on this (and other)
mailing-list(s).


Aninda DasGupta ([email protected]) Ph:(914)945-6071 Fax:(914)945-6552
Philips Labs\n 345 Scarborough Rd\n  Briarcliff Manor\n NY 10510

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

Reply-To: [email protected] (Robert J. Keller)
Date: Fri, 17 Dec 1993 23:15:09
Subject: Re: Two Cellphones With Same Number? - Not Permitted
From: [email protected] (Robert J. Keller)


Here is what the Federal Communications Commission has to say on
the subject:

:: Quote ::

   PUBLIC NOTICE

   FEDERAL COMMUNICATIONS COMMISSION

   COMMON CARRIER PUBLIC MOBILE SERVICES INFORMATION

   October 2, 1991
   Report No. CL-92-3

   CHANGING ELECTRONIC SERIAL NUMBERS ON CELLULAR
   PHONES IS A VIOLATION OF THE COMMISSION'S RULES


   It has come to the attention of the Mobile Services
   Division that individuals and companies may be altering
   the Electronic Serial Number ( ESN)  on cellular phones.
   Paragraph 2.3.2 in OST Bulletin No. 53 (Cellular System
   Mobile Station - Land Station Compatibility Specification,
   July, 1983) states that "[a]ttempts to change the serial
   number circuitry should render the mobile station
   inoperative." The 1981 edition of these compatibility
   specifications (which contains the same wording) was
   included as Appendix D in CC Docket 79-318 and
   is incorporated into Section 22.915 of the Commission's
   rules.

   Phones with altered  ESNs do not comply with the
   Commission's rules and any individual or company operating
   such phones or performing such alterations is in violation
   of Section 22.915 of the Commission's rules and could be
   subject to appropriate enforcement action.

   Questions concerning this Public Notice should be addressed
   to Steve Markendorff at 202-653-5560 or Andrew Nachby at
   202-632-6450.

:: End Quote ::

The staff has informally opined (although the Commission has not yet
formally ruled) that the foregoing prohibits, in addition to the
direct cloning and/or manipulation of the ESN, many of the other
schemes to get around it by "intercepting" and "translating" the ESN.
They have proposed the following rule which will likely be formally
adopted sometime early next year:

:: Quote ::

   22.919 Electronic serial numbers.

   The Electronic Serial Number (ESN) is a 32 bit binary
   number that uniquely identifies a cellular mobile
   transmitter to any cellular system.  Each mobile
   transmitter must have a unique ESN and must comply
   with the following specifications.

       (a) The ESN must be factory set and must not be
       alterable, transferable, removable or otherwise able
       to be manipulated in the field.

       (b) The ESN host component must be permanently attached to
       a main circuit board of the mobile transmitter and the
       integrity of the unit's operating software must not be
       alterable.  The ESN must be isolated from fraudulent
       contact and tampering.  If the ESN host component does
       not contain other information, that component must not
       be removable, and its electrical connections must not be
       accessible.  If the ESN host component contains other
       information, the ESN must be encoded using one or more
       of the following techniques:

           (1) multiplication or division by a polynomial;

           (2) cyclic coding;

           (3) the spreading of ESN bits over various
           non-sequential memory locations.

       (c) Cellular mobile equipment must be designed such that
       any attempt to remove, tamper with, or change the ESN
       chip, its logic system, or firmware originally programmed
       by the manufacturer will render the mobile transmitter
       inoperative.

:: End Quote ::

As far as staff is concerned, the proposed rule merely clarifies what
is already the law, but they feel that the clarification in necessary
because many in the industry are coming up with so many novel ways to
accomplish the same result in clever ways.

IMO, this is not something to be taken lightly for two reasons:

(1) the FCC has gotten rather aggressive in recent years in the number
and size of forfeitures (read "fines") imposed for (even relatively
minor) rules violations, and

(2) doing something like this when your carrier does not authorizes
subjects you to the risk that your cellular unit will be negatively
listed (and therefore rejected as a fraudulent unit).

Note, however, that the staff does _not_ consider it to be a violation
for the cellular carrier to offer this capability by doing some
programming at the cellular switch that associates a single phone
number with two or more _different_ ESN's.  Apparently some carriers
are starting to do this.


Bob Keller (KY3R) Tel +1 301.229.5208
[email protected] Fax +1 301.229.6875
[email protected] CIS 76100,3333

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

From: [email protected] (Aaron L Dickey)
Subject: Mobilnet - Do They Know This?
Organization: The World Public Access UNIX, Brookline, MA
Date: Fri, 17 Dec 1993 21:10:23 GMT


The following is being forwarded for the benefit of Douglas Adams:

[email protected] (Douglas Adams) writes:

There have been some very expensive and elaborate ads on CNN recently for
Mobilnet. As far as I can divine (the ads are heavier on production values
than on information) they are offering a nationwide cellular service which
eliminates the need for fiddling about with roaming codes etc.

If this is what they are offering then I am extremely interested in it --
definitely a potential customer. Though I 'm British, I spend a great deal
of time travelling round and round the States and 'cell-comms-made-simple'
is exactly what I want.

Right at the end of the ad they flash up a 1-800 number for enquiries. By
the time I've grabbed a pencil its gone and I haven't got the number. This
has happened several times. I suddenly realize it's _that_ ad, (it takes a
while to spot it because it starts out like an ad for shampoo or beer or
something) and have just been too late to get the number.

So I've tried the 800 information service, which has no listing for
Mobilnet.

Now, I can't help wondering if the people at Mobilnet are sitting
manning their phones and thinking 'Hmmmm -- doesn't seem to be much
demand for this service. Maybe the folks out there don't really want a
national cellular system ...'

I think there should be some kind of award for advertising of this
nature.

Incidentally -- if anybody _does_ have the Mobilnet number I'd be glad
to have it -- provided they haven't shut down the business for lack of
demand.


Douglas Adams    [email protected] (current)
                [email protected] (dormant)

(message passed along by)

Aaron Dickey [email protected]


[Moderator's Note: I tried 800-555-1212 just now hoping to find an
answer, but 800 directory has nothing listed for the company. Anyone
else know how to reach them?  PAT]

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

Date: Fri, 17 Dec 93 20:26:26 -0800
From: Samir Soliman <[email protected]>
Subject: Re: PCS Questions


At  11:31:06 CST 12/14/93 Kyle Griffin wrote:

> Although there are strong proponents of making GSM (or a modified
> version) a US standard, there's no guarantee that will happen. The FCC
> has stated that they would rather let the market determine standards
> rather than dictate any. There are also proponents of CDMA. I've seen
> some of the TDMA-CDMA dialogue in this digest. I'm not on either
> "side" of the issue. From what I've read (from people not related to
> any company making either type of equipment), as well as an
> acquaintance at Bellcore, there is a general feeling that, as far as
> capacity is concerned, when all is said and done, they're going to
> come out about equal in terms of increased capacity over cellular AMPS
> (approximatly 7 to 1).

I don't want to argue numbers here.  But keep in mind that GSM is not
designed for capacity or spectral efficiency.  The design objective
for GSM was politically motivated. In the US spectrum is becoming a
very expensive commodity and a need for an efficient multiple access
scheme becomes a necessity. I recommend that every one interested
reads the article published by THE ECONOMIST entitled "Falling to
bits" dated May 29, 1993.  In that article, the author writes "The
ambitious eight fold gain that Europe is aiming for has proved equally
elusive. GSM averages a two-to-threefold gain. In Hong Kong, where the
complicated city-scape tends to disperse the signal, GSM has managed
to improve things by a mere 50%"

The PCS radio environment is similar, if not worse than the Hong Kong
environment (small cells, dense urban, severe mulipath, high traffic
volume, in-building coverage requirements, etc. ...).

I would like to hear from anyone who worked or still working on the
GSM system in Hong Kong. What was (is) his/her experience with getting
the system to work in Hong Kong? What is the capacity of that system
compared to AMPS?.

I would like also to hear how painful was it to replan the frequency
at least once a month or as often as you add one more sector or cell
as the system grows with time.


Samir Soliman   Qualcomm Incorporated

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

From: Lynne Gregg <[email protected]>
Subject: Re: Wireless LANs
Date: Thu, 16 Dec 93 08:57:00 PST


Original note:

> I am looking for a way to send Ethernet across a public street. Somebody
> told me there is a $2500 pair of laser devices that can do that. Another

Response:

> John Levine, [email protected], {spdcc|ima|world}!iecc!johnl
> I'm surprised that nobody's mentioned NCR Wavelan.  It's a 2 mb/sec

Another option is Motorola Altair.  They may be above 2mb by now.
They also had some interesting methods of extending distance, combining
both infrared (line of sight) and radio receivers.  Multiple protocol
support's available, too.


Regards,

Lynne

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

Date: Sat 18 Dec 93 00:07:58 EST
From: Tony Harminc <[email protected]>
Subject: Re: Saudi Arabia NANP Area Code


> [Moderator's Note: Yes, Saudi Arabia had an international country code
> like all other countries, but it also had an 'area code' which could be
> dialed from the USA for the administrative convenience of some people.
> The oil industry?  I dunno. Anyone remember the 'area code' number, and
> does it still work today?   PAT]

I have a business card that I got in 1981 or 1982 from someone working
in Saudi Arabia.  It is laid out like this:

    ----------------------------------------------------------------
                       KINGDOM OF SAUDI ARABIA
               Ministry of Finance and National Economy
       The National Center for Financial and Economic Information

                              <name>
                   Asst Coord for Tech Operations

   USREP/JECOR/NCFEI                              P.O. Box 6902
   APO New York 09038                       Riyadh, Saudi Arabia
   Ph: 404-0544                                   Ph: 404-3945
   ----------------------------------------------------------------

The same (I presume) information is on the other side in Arabic.

There is no area code -- just seven digits for each number, but
perhaps the implication that both are NYC numbers, but one rings in
Riyadh?  Or perhaps both are Riyadh numbers, but one rings in a P.O.
box in New York. :-)


Tony Harminc

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End of TELECOM Digest V13 #824
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