File Delimiters on AES 256 Encrypted fields

Question

I have a requirement for one of my projects in which I am expecting a few of the incoming fields encrypted as AES-256 when sent to us by upstream. The incoming file is comma delimited. Is there a possibility that the AES encrypted fields may contain "," throwing off the values to different fields? What about if it is pipe delimited or some other delimiter?

Also, how what should be the datatype of these encrypted fields in order to read these encrypted fields using an ETL tool?

Thanks in Advance

Answer 1

AES as a block cipher is a family of permutations selected by the key. The output is expected to be random ( more precisely we believe that AES is a Pseudo-Random-Permutation)

AES ( like any block cipher) outputs binary data, usually as a byte array and bytes can take any value between 0 and 256 with equal probability.

You are not alone;

Transmitting binary data can create problems, especially in protocols that are designed to deal with textual data. To avoid it altogether, we don't transmit binary data. Many of the programming errors related to encryption on Stack Overflow are due to sending binary data over text-based protocols. Most of the time this works, but occasionally it fails and the coders wonder about the problem. The binary data corrupts the network protocol.

Therefore hex, base64, or similar encodings are necessary to mitigate this. Base64 is not totally URL safe and one can make it URL safe with a little work.

And note that has nothing to do with security; it is about visibility and interoperability.