Software Vault: The Diamond Collection/The Diamond Collection (Software Vault)(Digital Impact).ISO/cdr16/tc14_456.zip/TC14-456.TXT

Text File | 1995-01-22 | 13KB | 326 lines

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From: [e-mail] (Jeffrey Rhodes)
Subject: Re: Caller-ID With Call-Waiting
Date: 19 Dec 1994 21:58:15 GMT
Organization: McCaw Cellular Communications, Inc.
Reply-To: [e-mail]


McCaw Cellular (Cellular One) systems will be able to offer Caller-ID
with Call-Waiting on TDMA IS-54 rev B compliant phones next year.  An
Alert With Info message is used for the initial call (five messages
are needed on an analog voice channel but only a single message is
needed on a digital voice channel). Flash With Info message is used
during call-waiting setup.

Subscribers will need to purchase CLIP Calling Line ID Presentation in
order to see unrestricted caller numbers. Without this feature, the
terminal will display "Call" or whatever it displays today without
CLIP.

When the number delivered is restricted, i.e. the caller has the CLIR
feature authorized and active, then the CLIP authorized and active
display will show "Private". Callers with CLIR unauthorized, i.e
"allow the display of my number to a CLIP authorized and active
terminal", or CLIR deactive (deactivated per-call by *82 prefix) will
show the CNI.

When the CPN is not delivered, usually because the IXC carrier drops
it, the CLIP authorized and active terminal will display "No ID" or
"Out of Area".

Incidentally, we prefer to use the terms CNIP and CNIR instead of CLIP
and CLIR. Interstate Calling Number ID will be possible in mid-1995
due to the FCC mandate to deliver CPN which is the Calling Party
Number of ISUP signalling. CPN consists of the ten digit caller's
number preceed by two Presentation Indication bits (00 means "allow"
01 means "restrict").

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From: [e-mail]
Subject: Re: T3 Framing Standard
Date: 19 Dec 1994 03:06:27 GMT
Reply-To: [e-mail]


In <[e-mail]>, Lew Gutman <[e-mail]>
writes:

> I'm looking for the standard which defines the frame structure of a
T3
> carrier.  I tried to order ANSI T1.103-1987 and T1.103a-1990 from
> ANSI, but they told me that these standards have been removed and
> there is no replacement.

The international standard is ITU-T G.752. You can download this from
the ITU gopher (info.itu.ch).

The historic de-facto US standard was CB-119. This is no longer
available from Bellcore but you might still be able to get it from
AT&T (for a fee, of course). The Bellcore "replacement" is
TR-TSY-000499 which can be had for a mere $153 in ransom.

An alternative Synchronous DS3 Format was defined in Bellcore
TR-TSY-000021 but this document is also no longer available.

DS-3 equipment has historically been designed to CB-119 or G.703 to
meet requirements at the "distribution frame" or "DSX3 Cross Connect".
Generally all DS-3 equipment expects B3ZS format signals at a bit rate
of 44.736 MBPS +- 20 ppm. You can generally pass any signal meeting
these specifications through a DS3 channel (Microwave or FO
multiplex). Framing is an actually an issue for the equipment at each
of the channel which of course must be compatible.

DS3 framing becomes an issue in carrier networks where equipment may
monitor the DS3 streams for performance and may initiate protection
switching when the monitored data indicates a transmission problem.
Such monitoring makes use of the DS3 format and its provision for
parity.

The most general desciption of a DS3 frame is as follows.

The frame structure consists of 4760 bits which are divided into 56
subframes of 85 bits each. The subframes can be arranged in 7 rows of
8 columns each depicted as follows:

X [84] F1[84] C11[84] F0[84] C12[84] F0[84] C13[84] F1[84]
X [84] F1[84] C21[84] F0[84] C22[84] F0[84] C23[84] F1[84]
P [84] F1[84] C31[84] F0[84] C32[84] F0[84] C33[84] F1[84]
P [84] F1[84] C41[84] F0[84] C42[84] F0[84] C43[84] F1[84]
M0[84] F1[84] C51[84] F0[84] C52[84] F0[84] C53[84] F1[84]
M1[84] F1[84] C61[84] F0[84] C62[84] F0[84] C63[84] F1[84]
M0[84] F1[84] C71[84] F0[84] C72[84] F0[84] C73[84] F1[84]

Transmission order is left to right top to bottom.  F1 is a one and F0
is a zero. The F bits define the basic frame structure. The two X bits
must always be the same. The two P bits are also the same and are the
even parity of all the data bits (the [84] bits) in the above format
from the previous frame. M0 is zero and M1 is one. The M bits
establish the multiframe structure.

The interpretation of the C bits and the data bits depends on the
format; SYNTRAN has one interpretation, G.752 (M13 Multiplexor has a
different structure. For G.752 the data bits in each row above
correspond with a DS2 stream. The 8th subframe of each row above
contains a "pulse justification postition" or "stuff bit". For the
first row it is the first bit, for the second row the second bit, etc.
The C bits in a particular row are transmitted all ones to indicate
that stuffing occurs in that row and all zero to indicate no stuffing
has occured. Receivers normally use majority voting. The stuff bit is
in any case included in the parity computation.

Hope this helps!


Wally Ritchie   Ft. Lauderdale, Florida

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From: [e-mail] (Steve)
Subject: Re: T3 Framing Standard
Date: 19 Dec 1994 20:42:01 GMT
Organization: Express Access Online Communications, Greenbelt, MD USA


I'm suprised that ANSI doesn't stock current specs for DS3.  I think
Bellcore might have something.  This worked a few months ago:

telnet info.bellcore.com
login as "cat10"  or "CAT10" (I can't recall if it's case sensitive)

This takes you to a search of their techpub catalog.

Take it easy,


Steve

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Date: 19 Dec 1994 08:27:08 GMT
From: Jim Burkit <[e-mail]>
Subject: Re: T3 Framing Standard


Lew Gutman <[e-mail]> wrote:

> I'm looking for the standard which defines the frame structure of a
T3
> carrier.  I tried to order ANSI T1.103-1987 and T1.103a-1990 from
> ANSI, but they told me that these standards have been removed and
> there is no replacement.

ANSI is correct.  T1.103 and T1.103a have been withdrawn.  This
standard however was only for the synchronous DS3 format known as
SYNTRAN.  SYNTRAN was not being used by US industry so when the
standard was in its five year review Committee T1 voted to withdraw
it.

Now to your real question.  The standard that controls most of the
format for DS3 signals is T1.107-1988.  In addition, T1.107a-1990 adds
the C-Bit Parity format.  I don't think that T1.107b-1991 adds any DS3
formats I believe that it just adds DS-0 data formats.  Note that
T1.107 has the formats for all of the north american asynchronous
digital hierarchy.

Additional standards that may be of interest are:

        T1.102-1993  Electrical interfaces
        T1.404  Network to Customer Interface.  A new issue was
        approved in 1994 but I am not sure if you can get it at
        this time.

By the way, T1.107 is being revised.  The three T1.107 (a and b)
documents are being put into one.  This revision is currently be voted
on by Committee T1 and the vote will close in January.  If you wish a
copy of the unapproved T1.107 you can ftp to ftp.t1.org and get

/pub/t1x1/3x4-0023.ps   postscript
/pub/t1x1/3x4-0023.ww2  Word for Windows 2.0
/pub/t1x1/3x4-0023.ww6  Word for Windows 6.0 (native version)

I hope this helps.


Jim Burkitt   T1X1 Chair

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From: [e-mail] (John Lundgren)
Subject: Re: Channelling Phone Line Through a Leased Line
Date: 20 Dec 1994 01:41:48 GMT
Organization: Pacific Bell Knowledge Network


Chuck Poole ([e-mail]) wrote:

> In article <[e-mail]> [e-mail] (Greg
> Tompkins) writes:

>> My whole purpose of doing this is to get away from paying LONG
>> DISTANCE CHARGES.  Location A is long distance to/from location B.
I
>> want to have a location A phone line in location B.  I have asked
>> about this before, but others have told me that I need a MUX and a
56k
>> line.  I would like to make this as inexpensive as possible.  The
two
>> locations are only 15 miles apart.

> If they are only 15 miles apart, an FX line may be cheaper than a
> leased line and there is no equipment necessary.

In my area, which is Pac Bell, the measured business line costs $17.25
a month, but the FX (Foreign Exchange) lines we have at our other
campus are an *additional* $25 a month, for a total of over $42 a
month.  Not cheap!  But as of Jan 1, the FX rates are going up even
further, to I don't know how much it will be.  And we have over a
hundred lines at that campus, most are FX.  That's a substantial
amount every month.

The FX may not be the choice for you.


John Lundgren - Elec Tech - Info Tech Svcs
Rancho Santiago Community College District
17th St. at Bristol \ Santa Ana, CA 92706
[e-mail]\[e-mail]

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Date: Mon, 19 Dec 1994 23:23:08 -0500
From: H.Shrikumar <[e-mail]>
Subject: Re: Information Wanted: Pulse Rate in India
Organization: UMass, Amherst MA + Temporal Systems Bombay India


In article <[e-mail]> was written:

>  I am setting up a modem for a friend of mine in India and the

> 1) make/break ratio of 39% / 61% and 10 PPS (USA/Canada)
>         [DEFAULT SETTING]
> 2) make/break ratio of 33% / 67% and 10 PPS (UK/Hong Kong)

I think according to DOT standards [sic] it is supposed to be this
one.

However, I must tip over my salt dumpster here :-)

1. A US modem installed there has practially always worked. And I have
done that with quite a few modems, in quite a few cities and surely
with quite a few exchanges.

2. There is enough tolerance in the exchanges to deal with the above
two at least, I should believe ... speaking entirely from the
knowledge that I have seen some really really creaky phone's with weak
decadic dialer springs, which was so obviously out of whack ... and
the call got thru.

(One of those phones once refused to dial 6 (no pulses on 6, dont know
how that could happen, but it did.) This was one of those old bakelite
moulded ITI phones .. and the hook-button has a nice feel to it, so I
just tapped a brisk 'HI' in morse code when I was to dial '6'. Thats
six pulses -- the call got thru each time. :-)

3. One of the lines at our office tho' is very very wierd. It just
would not dial the right number when we dialed with our modem (a
Multitech 224BAF) -- no matter what pulse ratio the modem was set to.
We tried all settings on two modems -- and even verified the ratio
with
a scope.

My morse dialing would always work, as would any phone instrument we
tried. Just not either of the two modems (same model) !!

We are now getting a bunch of Boca modems, so I plan to see if they
work on that line -- would be academically interesting.

4. In theory, it is supposed to be bad manners to set the pulse ratio
to a wrong one. (In some countries, the phone-police will get you :)

But then again, in theory the DoT is supposed to provide something
close to a phone service :-)

5. DoT standards generally is to do polarity reversal on all lines.
DoT standards is to enable only pulse dialling on the lines. But like
all other things-DoT the exception is now the rule.

So many of the newer lines are getting installed and initialised to
whatever seems like the default that the manufacturer put in during
production testing, and "no one cares". The result -- you know you
have a Japanese switch serving you in all likelyhood if your new line
does not do polarity reversal. In fact, MTNL had left DTMF
"accidentally" enabled on some new-fangled smart-card phones in Bombay
 -- some smart alecs found that you could use a DTMF beeper and make
free calls.  (Actaully I wonder if that "accidentally" was not at
least a little non-accidental :-)

Long story short -

Use that which works ... surely one of the 10 PPS settings should
work. Most likley both would.

Good luck !

> 3) make/break ratio of 33% / 67% and 20 PPS (Japan).

Not this one ... that's for sure.

My morse code is never that fast :-)


shrikumar ( [e-mail], [e-mail],
X.400 G=Shrikumar S=Hariharasubrahmanian P=itu A=arcom C=CH (yea right
:)

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End of TELECOM Digest V14 #456
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