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TUCoPS :: Phreaking Technical System Info :: testprfx.txt

Test Prefixes/Exchanges

Test Prefixes/Exchanges

BY: PhreakBlaze


Co codes, or nxx codes, are speacial exchnages or other 7 (or 3) digit
numbers for the maintnance of trunks. Most of them are not to be asigned
by NANPA for usage. They are to be saved for a central office to use as
a test/special codes/exchanges. These numbers differ from CO to CO.

What number's are Codes (usually)???:

Most co numbers/NXX codes are universal but with difrent uses. Some are
dialed useing 10 digit dialing (NPA-NXX-XXXX), 7 digit dialing
(NXX-XXXX), and even 3 digit dialing (NXX). I've also heard of dialing
(NPA-0XX-958), but I'm not sure what to do there. The comon numbers are
all N11 codes, 990, 959, 958, 950, 555, 976, 700, and then some only
used in your area.

What are the numbers for???:

Well, all the number's purposes differ from co to co (exept for certian
numbers, I'll discuss later). Wait, actually, the N11 codes, they
usually don't change. They are usually supposed to be asigned as:

211 - Community Information and Referral Services
311 - Non-Emergency Police and Other Governmental Services
411 - Local Directory Assistance
511 - Travel Information Services
611 -Repair Service
711 - Telecommunications Relay Service (TRS)
811 - Business Office
911 - Emergency
(Note- They are not suposed to be asigned by the NANPA, but instead the FCC.)

But this is not always true, the only ones I've seen constant are 911
(duh!), 711, and 411. (Note- Recently in my area, when I dial 611, it
says that the repair service in no longer available from that number,
and must be reached from an 800 number.) The only ones that have a
constant use are 700, and 976. The only way to dial 700 is
(NPA-700-4141) and thats the only number in that whole range. (Note- 700
is the only one that can be asigned as a NPA by the NANPA.) Then 976 is
used as pay services (they usually cost 1 dollar for a call to a
service, but if you want to know the services in there, then just dial a
wrong number, and a recording should tell you which numbers do what).
The rest do stuff.

Your ANAC, Ringback, and NXX test numbers (and you):

One of the things that these codes are almost always used for is the
ringback and ANAC for your co/area/region (in my case, state wide). In
the Garden State (New Jersey, DUH!!!) The ring back and Anac are the
same for the whole state. My RingBack and my Anac are
550-xxxx(ringback), and 958(ANAC). Now, incase you didn't notice, my
ring back is not one of the common codes, it is for this area/region
only. Now as most of us know, these codes are free when dialed from a
payphone, as are 990, 555, 959, 950, and all N11, but not 700, and 976.
Now the numbers that serve as a ringback and ANAC differ from place to
place (Note-place is a general term, place could be state, town, or even
CO). I've even seen ring backs be on N11 numbers, so check all your N11
numbers for ringbacks and ANACs. Another thing I've heard of is a SASS
unit being on a CO/Nxx code. I believe it was in Captian B's area on the
N11 code 311, it would play the number your calling from like a ANAC
but, it would do it twice, a ny time durring which, you could enter a
pass code. SASS units are not always on Co/Nxx codes, the sometimes have
pots lines. (Note- If your area has a SASS unit, then don't try to look
for ANAC or ring back once you find your SASS, a SASS is meant to
replace those CO/Nxx codes.)

I can't find my ANAC(or ring back), but I found my ringback(or ANAc),any

So, you can't find one of the two codes that does the ring back, or
ANAC? No worries, I have a theroy that may work for you.

***PhreakBlaze's Theroy For Finding Ring Back Or ANAc***
-go to

-click on the search your npa and ring back or anac code for the nxx. It
will most likely come up in a thing called "ODDBALLCODES" with no co
name, just some Xs for the co name. If it gives you a company name that
owns it :EX- Verizon East: click on it, if not, search you npa and your
exchange, then click on the company for your region/state like the
example above shows.

-Go down the list (it takes a bit to load) to where it starts listing
you NPA and exchanges in it. Then start going down the list till you see
and exchange served from the CO XXXXXXXXXX. The first exchange you'll
probably see being served by that is 211. Now all that you see with the
XXXXXXXXXX you slould write down (if its not one of the regular codes).

-Now go to a payphone or normal phone and dial the codes (Note-
sometimes, an ANAC will need a 7 digit number dialed, and other times

Don't worry aabout the rest of the unused exchanges, they are most
lilely just exchanges that aren't in use, not codes.

***End/PhreakBlaze's Theroy For Finding Your Ring Back Or ANAC/End***

Well, what else about these codes???:

Well, we now found (hopfully) our ANAC or Ring Back (or SASS), and maybe
something else fun on those codes. Well some of tghe codes I've played
with have not done anything except given me an error measage that I have
only heard when the code was not in service. As you may have also
noticed, I said they are free to be called from a payphone. The only
codes I've seemed to get working terminate at some place I don't know
about. Some I've gotten to go to "A Verizon VMS," and other have gone to
"network contrlers." Other times I've gotten people who answer and all
they say is "Verizon," and the wait for you to answer.

Any tip/resons for scanning this stuff:

Yes, I do have some tips. Well, I'm not so sure of how good you would be
at op diverting to it. Also, I'm not sure if there is any
possibility/way to get in trouble for scanning these, but it would take
the same amount of time to scan from a payphone as it would from home.
When you call one that works, it will ring for a long time (never
counted the rings), and then after two rings really close together, it
will actually start ringing the persons desk/answering machine/ or the
VMS picks up.

For tips on where tgo scan, I'm not sure this will help much, but around
here (so far) I've only been able to find number that work between
990-9000 to 990-9999 (Note- 990-9000 is the Verizon VMS around here.)

Thanks for reading...

Shouts: Y0ung Br1an, Phreak Out, Decoder, Captian B, Dual, StankDawg,
Icon, Dox, and everybody else at StankDawg's forums.

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