Submission for mod.telecom (FCC Registration)
la...@kitty.uucp.uucp
> > There are several methods used by the telco's for line testing. .....
> > By knowing WHAT is hanging on the end of your cable,
> > you can quickly tell the status of the pair AND the station.
> > This is why the telco's fought so hard about registration. They
> > really didn't care about the equipment, they just need to know what it
> > "looks" like, for trouble isolation purposes.
The only reason that operating telephone companies sought apparatus
registration was to assure themselves that no "harm" to the switched network
would result from improperly designed apparatus.
For example: apparatus which places signals of excessive amplitude
on a telephone line can cause crosstalk on other working lines; apparatus
which provides leakage current paths to ground can not only cause crosstalk
(by creating a longitudinal unbalance on the cable pair), but can also
upset automatic line insulation test apparatus into thinking that a cable
fault exists; etc.
The FCC Part 68 registration specifications were created to set a
uniform standard of what was acceptable as telephone apparatus without
creating trouble conditions for the operating telephone company.
While a "ringer equivalence" specification may give a telephone
company test bureau some idea as to the impedance terminating the subscriber
by the connected devices, for all intents and purpose, the telephone company
will never trust this information. If a cable problem presents itself, the
telephone company will generally send a craftsperson into the field to open
the pair at the subscriber location (or outside on a pole) before any test
measurements are taken. The telephone company would be naive to believe what
a customer reports as being their connected apparatus.
> HMMMM, it's been years now that I've taken the trouble to tell SWB about the
> latest changes in equipment that I've connected at my end - mainly, because
> it changes often and because I'm under the impression that they don't really
> care to know; or, at least, don't do anything with the information that I
> give them about my latest set of hardware (besides, it often changes on
> a daily basis; what with all these new modems, answering machines, phones and
> other gadgets to test and play with :-)
>
> Now, what I'd like to know is the following:
>
> 1) Can someone tell me what the phone company *SHOULD* be doing with the data
> describing my hardware?
Nothing, really, other than making note of the FCC registration number
on their "service billing record". Quite frankly, I have never known of an
operating telephone company that even checked to see if the FCC registration
number was a valid number for any piece of telephone apparatus.
> 2) Is there something that I should *INSIST* that SWB do in response to me
> reporting what I have connected?
Nope. Assuming that you have given a "valid" FCC registration number,
there is nothing that your operating telephone company can or will do, based
upon the nature of the apparatus that you have connected to the telephone line.
Your central office telephone loop will be designed according to
some already-established plan created by a facilities engineer. There may be
more than one plan in effect for a given central office, with the actual plan
being selected by the available serving cable facilities between the central
office and your location. For example, your line may run through a negative-
impedance repeater to meet an office transmission goal; or, your line may
run through a subscriber line concentrator if cable facilities are scarce; etc.
As a further example, New York Telephone generally tries to limit
subscriber loop loss to no more than 5.5 dB. Whatever combination of cable
and/or repeater facilities are available will be used to achieve this goal.
Subscriber lines for dial-up data use or PBX trunks are usually
available with a lower loop loss - but at an ADDITIONAL COST. You get what
you pay for - which means that for the price of a regular subscriber line you
get no choice of anything and no special treatment.
> 3) Is there some way that I can test that they *ACTUALLY DID* what needed to
> be done at their end?
Nope. Since they don't do anything, you can't very well test for
it. :-)
> 4) Can not reporting my latest set of hardware lead to *DEGRADING* in line
> quality somehow? for example, could this lead to degraded line quality
> for data communications using a modem (especially at 2400 baud)? or to
> another phenomenon, such as "not all connected phones ring during an
> incoming call"?
You might degrade your telephone line by, say, connecting too many
telephone sets with equipped ringers, but that is YOUR problem - not the
telephone company's. The telephone company is not going to do anything -
regardless of what you tell them.
> I guess, what I really need is a pointer to a book which really all that I may
> ever want to know about telephones and data-communications in a lingo I can
> understand and make sense of (i.e. don't require the background and knowledge
> of the lingo of a telecommunications engineer). Please, *DO* give pointers !!
Unfortunately, I don't know of a good book that would fulfill your
request. Books that I have seen are either: (1) insultingly simple, as
written for Joe and Mary Consumer, or (2) deal in theory, and therefore fail
to give immediate, practicable answers.
However, rather than leave you empty-handed, a good middle-of-the-road
book is "Telecommunications and the Computer", by James Martin, published by
Prentice-Hall, ISBN 0-13-902494-8.
<> Larry Lippman @ Recognition Research Corp., Clarence, New York
<> UUCP: {allegra|ames|boulder|decvax|rocksanne|watmath}!sunybcs!kitty!larry
<> VOICE: 716/688-1231 {hplabs|ihnp4|mtune|seismo|utzoo}!/
<> FAX: 716/741-9635 {G1,G2,G3 modes} "Have you hugged your cat today?"
how...@cos.uucp.uucp
One minor point (minor until it gets you): dial modems,
especially the higher speed ones, may not work properly
because the network interface device has resistors set
for voice use, not data. It is worth letting your telco
know you are running higher speed data, because your
network interface should then be configured to give you
better signal to noise ratios, not important for voice.
If they're going to charge more for data access, do this
only after you have unacceptable problems. Your problems,
however, often are in the jack, not the local loop.