Encrypting files in B2
Backblaze’s backup product has been encrypting customer data by default from the day it shipped in 2008. The files are encrypted on the user’s computer, transferred to Backblaze via an encrypted SSL connection and stored in the encrypted format. In fact, there is no way to turn it off. Flash forward to 2016, we’ve now encrypted billions of files and decrypted millions of files. The way encryption works in the online backup product is described on the Backblaze blog.
For B2, encryption had to be optional. Some use cases would require encryption, some would not. For an example implementation of encryption with B2, refer to this guide on github.