> double it for cryptographic signatures and reply-to metadata Ah, email, where a message of 114 characters with no formatting ends up over 9KB due to authenti

> double it for cryptographic signatures and reply-to metadata Ah, email, where a message of 114 characters with no formatting ends up over 9KB due to authentication and signatures, spam analysis stuff, delivery path information and other metadata. Sigh. Although I doubt this will end up as large as email, the lesson is that metadata can end up surprisingly large. In this instance, I think 1–2KB is probably more realistic than the half kilobyte of “double it”.