E-Mail Security
Summary
Description what this documentation is about.
Transport Layer Security (TLS)
TLS is a cryptographic protocol that secures communications over a network by providing confidentiality, integrity, and authentication. It is commonly used to secure connections between a client and a server, as well as between servers.
Confidentiality
- Data is encrypted during transit to ensure it cannot be intercepted and read.
- TLS uses asymmetric encryption during the handshake phase to securely exchange a symmetric session key, which is then used for fast and efficient encryption of the data.
Integrity
- Message Authentication Codes (MACs) ensure that any modification of the transmitted data is detected.
Authentication
- TLS uses digital certificates issued by trusted Certificate Authorities (CAs) to confirm the identity of the communicating parties.
- The server presents its certificate to the client during the handshake phase to prove its legitimacy.
- Optionally, mutual authentication can occur, where the client also provides its certificate.
How TLS operates
TLS operates in two stages:
- TLS Handshake Protocol
- This phase negotiates security parameters, including the cryptographic algorithms to be used (cipher suites).
- The server sends its certificate to the client, which verifies the certificate against trusted CAs.
- Optional client authentication can occur here if needed.
- A session key, that will be used as a symmetric key, is exchanged using encrypted key-exchange.
- MACs ensure that data integrity is preserved.
- TLS Record Protocol
- After the handshake, the Record Protocol manages the symmetric encrypted transmission of data.
- Data is encrypted using the session key established during the handshake.
- MACs ensure that data integrity is preserved.
Limitations
- In-Transit Only: TLS protects emails only during transmission. Once the email reaches the server or the recipient's device, the content is unencrypted and stored as plain text unless additional encryption is used.
- Intermediary MTAs: The sender cannot enforce TLS on intermediary Mail Transfer Agents (MTAs). Some MTAs may not support TLS, leaving messages vulnerable during transit.
OpenPGP
Confidentiality
Integrity
Authentication
Secure/Multipurpose Internet Mail Extensions (S/MIME)
Confidentiality
Integrity
Authentication
Step 1
Enter these commands in the shell
echo foo echo bar
Step 2
Make sure to read
- War and Peace
- Lord of the Rings
- The Baroque Cycle
Used Hardware
Device to be used with this documentation Maybe another device to be used with this documentation