AS per the GDPR I see no possible solution for the “reasonable measure to verify the identity of a data subject” against an IPv4 IP and thus to reliably act on IPv4 related data subject access/deletion requests.
Also per the GDPR, providing data to the wrong person could “affect the rights and freedoms of others” in which case you shouldn’t provide the data.
AS per the GDPR I see no possible solution for the “reasonable measure to verify the identity of a data subject” against an IPv4 IP and thus to reliably act on IPv4 related data subject access/deletion requests.
Also per the GDPR, providing data to the wrong person could “affect the rights and freedoms of others” in which case you shouldn’t provide the data.