A new mail transport protocol is proposed for use over a reliable
byte-stream transport. This protocol is faster, simpler and more
streaming than prior methods, and handles binary and unicode data more
efficiently. The protocol requires fewer communication round trips
between servers per message transferred than existing methods. It
transmits and receives byte data as is without requiring further per-byte
processing on advanced operating systems such as UNIX, and requires only
new-line processing in text on legacy operating systems.