SMTP Vs ESMTP

Following trends of my previous posts Differences IPv4 Vs IPv6, Differences Routing Vs Routed protocol and Load Testing Vs Stress Testing, below is another one for differences SMTP Vs ESMTP.

SMTP	ESMTP
Stands for Simple Mail Transfer Protocol	Stands for Extended Simple Mail Transfer Protocol
First command in SMTP session: HELO techsutram.com	First command in ESMTP session: EHLO techsutram.com
RFC 821	RFC 1869
SMTP ‘MAIL FROM’ and “RCPT TO’ allows size only of 512 characters including <CRLF>.	ESMTP ‘MAIL FROM’ and “RCPT TO’ allows size greater than 512 characters.
SMTP alone cannot be extended with new commands.	ESMTP is framework that enhances capability to extend existing SMTP commands

If you are aware of any improvements to above differences or want to add to the above list then please post your comments below.