As Prof Bill Buchanan OBE on LinkedIn points out, the Brexit Trade Agreement [1] on Page 921 goes: The underlying certificate used by the s/MIME mechanism has

As Prof Bill Buchanan OBE on LinkedIn points out, the Brexit Trade Agreement [1] on Page 921 goes: The underlying certificate used by the s/MIME mechanism has to be in compliance with X.509 standard. In order to ensure common standards and procedures with other Prüm applications, the processing rules for s/MIME encryption operations or to be applied under various Commercial Product of the Shelves (COTS) environments, are as follows: – the sequence of the operations is: first encryption and then signing, – the encryption algorithm AES (Advanced Encryption Standard) with 256 bit key length and RSA with 1024 bit key length shall be applied for symmetric and asymmetric encryption respectively, – the hash algorithm SHA-1 shall be applied. s/MIME functionality is built into the vast majority of modern e-mail software packages including Outlook, Mozilla Mail as well as Netscape Communicator 4.x and inter-operates among all major email software packages. [1]https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/948104/EU-UK_Trade_and_Cooperation_Agreement_24.12.2020.pdf https://assets.publishing.service.gov.uk/government/uploads/...