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Can other party receiving 0800 call see withheld number?

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Pamela

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Nov 2, 2021, 11:57:28 AM11/2/21
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If you call an 0800 number then can the other party see your number even
if you withhold it?

As the receiving party are paying for the call, I'm wondering if they can
log incoming numbers (perhaps for billing purposes).

notya...@gmail.com

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Nov 2, 2021, 1:22:19 PM11/2/21
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No, well not legally, unless it happens to be the police. As it happens the calling number is carried in the call, and some PABX's can log this...

Woody

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Nov 2, 2021, 1:54:59 PM11/2/21
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The calling number is carried with the call - well, almost - along with
some data flags such as International, and one of which is withheld
number. The destination exchange responds to the flag and withholds the
number.
The emergency service system ignore the flags so they can see the
originating number.

Pamela

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Nov 3, 2021, 3:32:47 AM11/3/21
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On 17:54 2 Nov 2021, Woody said:

> On Tue 02/11/2021 17:22, notya...@gmail.com wrote:
>> On Tuesday, 2 November 2021 at 15:57:28 UTC, Pamela wrote:
>>> If you call an 0800 number then can the other party see your
>>> number even if you withhold it?
>>>
>>> As the receiving party are paying for the call, I'm wondering if
>>> they can log incoming numbers (perhaps for billing purposes).
>>
>> No, well not legally, unless it happens to be the police. As it
>> happens the calling number is carried in the call, and some PABX's
>> can log this...
>>
>
> The calling number is carried with the call - well, almost - along
> with some data flags such as International, and one of which is
> withheld number. The destination exchange responds to the flag and
> withholds the number.

I am not clear what you mean by "destination exchange". Would a
destination exchange include a company's PABX which the other poster here
mentions?

> The emergency service system ignore the flags so they can see the
> originating number.

What about governement organisations like HMRC, where some departments
(such as VAT collection) seem to have more authority than usual to
override personal privacy?

Alternatively a local council with powers to investigate who's who to
collect council tax?

Woody

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Nov 3, 2021, 4:27:10 AM11/3/21
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On Wed 03/11/2021 07:32, Pamela wrote:
> On 17:54 2 Nov 2021, Woody said:
>
>> On Tue 02/11/2021 17:22, notya...@gmail.com wrote:
>>> On Tuesday, 2 November 2021 at 15:57:28 UTC, Pamela wrote:
>>>> If you call an 0800 number then can the other party see your
>>>> number even if you withhold it?
>>>>
>>>> As the receiving party are paying for the call, I'm wondering if
>>>> they can log incoming numbers (perhaps for billing purposes).
>>>
>>> No, well not legally, unless it happens to be the police. As it
>>> happens the calling number is carried in the call, and some PABX's
>>> can log this...
>>>
>>
>> The calling number is carried with the call - well, almost - along
>> with some data flags such as International, and one of which is
>> withheld number. The destination exchange responds to the flag and
>> withholds the number.
>
> I am not clear what you mean by "destination exchange". Would a
> destination exchange include a company's PABX which the other poster here
> mentions?
>
The destination exchange is the BT exchange to which your domestic
telephone is attached. It recovers your call from the incoming data
stream that started at the exchange to which the caller is connected,
reads the flags, and acts appropriately.

This is why if you get a scam call from a Voip line with a sender
selected number you can sometimes have CLI showing International
followed by a correctly formatted UK number, or what appears to be an
international call but without the International flag albeit I
acknowledge that not all phones show them every time.


>> The emergency service system ignore the flags so they can see the
>> originating number.
>
> What about governement organisations like HMRC, where some departments
> (such as VAT collection) seem to have more authority than usual to
> override personal privacy?
>
> Alternatively a local council with powers to investigate who's who to
> collect council tax?
>

I cannot confirm the above but as far as I know only the emergency
services have that facility.

Emergency services certainly comprises Fire, Police, Ambulance,
Coastguard, Mines Rescue (if they still exist) and a couple of others
but I doubt Government departments (bar the secret squirrels) or local
authorities have such access. BUT I could be wrong.

David Woolley

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Nov 3, 2021, 7:13:02 AM11/3/21
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My understanding is that they get to see the ANI, rather than the CLI,
however, it is possible that this is a North American thing, and
therefore possible that it is not available in the UK.

ANI is accounting number indication, which indicates who would have paid
for the call, if it hadn't been paid for by the callee.

As emergency services were mentioned, they also get other special
treatments, e.g. calls can only be released by them, at least for
landline calls, whereas, for normal calls, only the caller can release
the call, although the time delay before the network will release the
call after the callee hangs up has been drastically reduced in the last
decade.

Angus Robertson - Magenta Systems Ltd

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Nov 3, 2021, 7:44:29 AM11/3/21
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> The destination exchange is the BT exchange to which your
> domestic telephone is attached. It recovers your call from the
> incoming data stream that started at the exchange to which the
> caller is connected, reads the flags, and acts appropriately.

While BT may honour the CLIP flags for most of it's customers, many calls are
routed instead to the hundreds of other licensed operators in the UK who
historically offered ISDN30 and now VoIP to large companies.

OLOs are supposed to also honour the CLIP flags, but this is a commercial world
and ignoring number withheld requests may be service offered to end users, or
may even be a requirement so calls can be geographically routed to different
calls centres or branches.

Angus

notya...@gmail.com

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Nov 3, 2021, 9:12:54 AM11/3/21
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When we had ISDN we also had COLP, which meant when you called a switchboard or 08xx number etc. and they hadn't prevented this, you could see where the call had actually gone, although bear in mind that some 0800 calls are normally terminated.

Woody

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Nov 3, 2021, 1:56:16 PM11/3/21
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Surely that last bit is what presentation numbers - such as those
starting 03 - are designed to handle? That way BT handle the routing and
the end users doesn't need to know the number or location.

notya...@gmail.com

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Nov 6, 2021, 2:38:10 PM11/6/21
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03xx numbers don't just belong to BT - you can get them on VOIP.
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