STARTTLS definition
STARTTLS is a protocol command used in communication protocols to initiate a transition to a secure channel from an insecure one. For example, often employed in email communication, this command signals the need to upgrade to a Transport Layer Security (TLS) encrypted connection, which provides secure data exchange by encrypting all data sent over the connection.
See also: SSL encryption, VPN gateway
STARTTLS examples
- Email communication: SMTP servers use the STARTTLS command to initiate an encrypted channel for email transmission.
- Internet relay chat: IRC servers use STARTTLS to upgrade to a secure connection.
Advantages and disadvantages of STARTTLS
Pros:
- Encryption: STARTTLS enhances data security by initiating an encrypted connection, securing sensitive information from prying eyes.
- Flexibility: It allows for an upgrade from an insecure connection to a secure one without the need for separate ports for secure and insecure connections.
Cons:
- Downgrade attacks: STARTTLS can be susceptible to downgrade attacks, where the attacker intercepts the STARTTLS request and forces the connection to remain insecure.
- Not compulsory: The decision to upgrade to a secure connection using STARTTLS is optional, which means some services may continue to send information over insecure connections.
Using STARTTLS
- Ensure your email or chat server supports STARTTLS to take advantage of secure communication.
- Combine the use of STARTTLS with a VPN for an additional layer of security.