Email Security and its Basic Elements (2024)

Introduction

The Purpose of this article is to provide a simplified version of email security basic elements . What does it mean , how email works and what are the key components of email security.

Email security can be defined as the use of various techniques to keep the sensitive information in email communication and accounts secure. In order to understand email security , one needs to understand on how email works and what are the different elements that comprise of an email system . It is also important to know that the whole objective of email security is to ensure that the end users (individuals or corporate) receive secure and safe emails .Users should not waste their valuable time in filtering good email from the bad emails .

In order to show how email works , I was able to find a very good diagram which I will share here . It is taken fromKavi Help Centerand you can see how an email flows from a sender outbox to recipient mailbox using the company mail server as well as the Internet . If you want to understand each step , Please refer to thesource link.

All the emails are sent and received using SMTP protocol .SMTP Stands for Simple Mail Transfer Protocol and uses Port 25 . SMTP was initially defined in RFC 821 which was later revoked byRFC 2821. Some of the key terms for email security are given below .

• SMTPS (SMTP Secure via TLS OR SSL and Port is 567) is encrypted email however this protocol is not used widely

• TLS (Transport Layer Security) is used to send email securely (Encrypted) between Two Servers by issuing STARTTLS command

• MTA is a very common term .It is short for Mail Transfer Agent and is used for any SMTP Server sending and receiving emails

• MUA is short for Mail User Agent and refers to any Email Client

SMTP Response Codes is a way for servers to communicate or talk with each Other . If an Email is not being delivered , always look at the Response code given by Destination Server .

Here are some common SMTP Response Codes .

• 220 –SMTP Service Ready

• 221 –Service Closing

• 250 –Requested Action taken and Completed

• 421 –Please Try Later OR Service is not available

• 50x –Server Could not recognize the command

• 550 –No Such User Here OR User Mailbox not Available

The most Important part about SMTP or email security is to know about the DNS Records as they have a vital role in Email flow .

• MX Record-It is a DNS Record which is created to show which server will receive emails for an organization . It is very Important for any organization . Without an MX Record ,you can’t receive emails for your domain/organization .