Re: [Proposal] Table-level Transparent Data Encryption (TDE) and KeyManagement Service (KMS)

On 2019-Jul-05, Bruce Momjian wrote:

> What people really want with more-granular-than-cluster encryption is
> the ability to supply their passphrase key _when_ they want to access
> their data, and then leave and be sure their data is secure from
> decryption.  That will not be possible since the WAL will be encrypted
> and any replay of it will need their passphrase key to unlock it, or the
> entire system will be unrecoverable.

I'm not sure I understand why WAL replay needs the passphrase to work.
Why isn't the data saved in WAL already encrypted, which can be applied
as raw bytes to each data block, without needing to decrypt anything?
Only if somebody wants to interpret the bytes they need the passphrase,
no?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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