hpr-knowledge-base/hpr_transcripts/hpr2628.txt

Episode: 2628
Title: HPR2628: UK Telephone Network Exploration
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr2628/hpr2628.mp3
Transcribed: 2025-10-19 06:45:00

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This is HPR Episode 2628 entitled UK Telephone Network Exploration.
It is posted by first-time post-extrato and in about 10 minutes long and carrying a clean
flag.
The summary is, I describe the process on finding interesting phone numbers on the UK Telephone
Network.
This episode of HPR is brought to you by archive.org.
Research Universe will access to all knowledge by heading over to archive.org forward slash
donate.
Hello everyone, so today I'm going to be talking about some of the interesting phone numbers
I've found on the UK Telephone Network.
I must purpose this by saying that much of this project took place a few years ago now.
I started reading Ghost in the Wires by Kevin Mitnik and exploding the phone by Phil Lapsley
and I found it quite unfortunate that most of the phone exploration that took place in
those books no longer really exists anymore.
So I decided to try and discover some interesting phone numbers on the UK Telephone Network.
Before I begin it would be beneficial to give a brief introduction on the UK phone network.
So most of the infrastructure is owned by a company called BT which is British Telecom
and it used to be owned before then by a company called GPO which is the general post office
but it revolved into British Telecom in 1984.
So although BT owns much of the physical infrastructure, third-party telephone providers
like Talk Talk and Sky rent the BT's infrastructure through a process called local loop unbundling.
So UK phone numbers split into two parts.
The first part is the area code and the second part is the local number.
So the first digit in the phone number is the trunk prefix which in the UK is zero.
So all national calls start with a preceding zero.
The next digit is the service type.
So for geographic area codes like cities and counties, this will be a zero one or zero two.
Zero three is for non geographic numbers.
Zero five is for corporate numbers and VoIP services.
Zero seven which is for mobile phone numbers.
Zero eight which is for free phone numbers, toll free numbers and then zero nine is for premium rate phone numbers.
So the next two to five digits are the area code and this is also called the dialing code.
And the last four to eight digits are the local code.
So if you want to dial phone number with the same area code,
you would only need to dial the local code for that code to be placed.
So it's also worth mentioning that BT engineers use line test number to perform various diagnostics on the line.
So this phone number is one seven zero seven zero and can only be reached through a BT landline phone.
The following recording is an example of the options available to BT engineers when this number is dialed.
It was recorded using an induction coil through a landline telephone.
This is a test phone call to one seven zero seven.
This circuit is defined as BT line test facilities.
Please press once the ring back to the quiet line, three fast test, four for fast cleanse or cleanse.
You have accessed BT fast test system.
Press one, it has been authorized to use the system for the new enhanced fastest options,
including copper, distro line test and remote intemulation press one.
Please press one for copper line test, two for digital test options,
three for test results, four for cable pair identification, five for BSL network check,
DSL frame jumper check and tamp switching, six for LLU options, seven for remote intemulation,
eight for GIA combined test or clear down.
It's worth noting that almost all the tests that can be performed on this line test number require a pin to be entered.
This pin I'm assuming is handed out to BT engineers.
So to find other interesting phone numbers on the UK telephone network,
I used a tool called Warvox, which is software created by HD Moor,
which can be configured with your Ix provider to dial banks or phone numbers and record the results.
So by googling Iax providers, you'll find endless results of providers that you can use to configure with Warvox.
So this can be download, Warvox can be downloaded from GitHub at github.com,
four slash rapid seven, four slash Warvox, so that's W-A-R-V-O-X.
And the instructions to install the software will provide you on that page.
So once you've installed and run the software, it will create a local web interface on port 7777.
And by opening the browser and browsing to 127.0.1 colon 7777,
it will bring up the Warvox interface.
And from here you'll be able to configure Warvox with your Iax settings and create this and start automated dialing.
So the phone numbers are entered in a format where the variable digits are replaced by X's.
So if you were to create a job with the phone number 016xx00000,
it would dial all 100 variations of that phone number withxx replaced with all digits from 00 to 99.
Once Warvox has completed the dialing, you'll be presented with a list of phone numbers that have answered,
and they all have recordings available that you can listen to through the web interface.
It also makes a guess as to what type of recording it is,
whether it's a human voice, a fax machine, or a modem.
So what I decided to do was dial multiple area codes with identical digits in the local part of the phone number.
For example, I'd dial as part of the bank phone numbers to be dialed 01621000000000000,
or 01204555555x, so all the local digits are identical.
I figured it would be unlikely that these phone numbers would have humans on the other end of the line,
and I didn't really want to disturb anyone with the dialing.
So all of the numbers dialed in total during my scan, 56 of them were answered,
two being answered by humans and the rest by machines.
Many of the numbers were advertising the number being for sale,
as you can hear in the following recording.
The number you've called is not currently in service.
If you're interested in using the number,
or would like more details about the services we offer,
please visit www.net.co.net.
With some of the other numbers that had been dialed, they were answered,
but they were answered in recording stating that the number was unavailable.
Sorry, but the number you have called is currently unavailable.
Number you have dialed is not in service.
Please check the number and try again.
Zero, one, two, one, two, one, one, one, one, one, one, one.
This telephone number is not in operation.
Thank you.
Some of the other calls were answered with voice mail boxes, as you can hear here.
Please enter your pin number followed by the hash key.
Welcome to Paragon Voice Mail.
Press star to leave a quick message.
Press hash to onto your mailbox.
Or hold to speak to an operator.
Please enter your mailbox number.
And others went to systems that require you to log in.
It didn't specify what the log in was for, but I just assume they'll be for mailboxes as well.
Your call to ID is not being recognized by our system.
Please enter your local phone accounts number.
Some of the numbers picked up with strange tones playing down the line, as you can hear
in these next two recordings.
Some of the phone calls got through to test lines as well, which provided some interesting
results.
This is BANDex Test Service.
You have reached the test number, 0, 1, by 1, 7, 0, 0, 0, 0, 0, 0, 2, 3, S, node, E, K, S, 0, 3.
Your test call has been successful.
Your test call has been successful.
This is a test mobile number.
This is a test mobile number.
You have reached the IT Exchange VoIP Test Number Service.
V, P, 0, 1, 0, 1, 5, 1, 7, 0, 0, 0, 0, 0, 0, 0.
OK, so those were some of the example recordings I retrieved from the automated dialing.
If you have any questions, feel free to leave them as a comment on the show page or you can
contact me via email at james.com.
So that's J-A-M-E-S, at J-A-M-E-S-D-O-T-C-R-M.com or on Twitter at at Extrato.
That's at X-T-R-A-T-O.
Thank you for listening.
Goodbye.
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