On 2022-03-05 at 11:06 -0600, hey joe wrote:

> usenet groups, is your IP address or any other personally identifiable
> information ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> ^^^^^^^^^^^
> stored in the posts or threads you create?

I am replying a little late to mention another important issue: your
news server might add other non-standard headers that, even if they do
not mention your IP address, make all of your posts at the very least
recognisable as written using the same account -- with the server
organisation (but not the public) being able to know much more about
you, including IP addresses, connection history plus email address and
any information you gave at registration time.

This is the case for at least one of the popular public-access Usenet
providers -- I will not give details here, even if I do not think they
are actively trying to hide this information: a technical user will
notice it quite easily.
I would not be surprised if most or all providers did the same.

The organisation I am talking about includes this identification header
with a value which is unique for each *account* (one can only post after
begin logged-in), but a similar effect could be achieved by other means:
for example by including a header contained the IP address encrypted
with a symmetric key only known by the organisation. One could imagine
other information such as connection latency being included.

One should certainly *not* rely on information posted on Usenet being
anonymous, without knowing much more.

--
Beard