SMTP Supported Ciphers

TLS ciphers supported by ImprovMX SMTP servers

ImprovMX's SMTP servers support encrypted connections via TLS or STARTTLS with a comprehensive range of ciphers and protocols spanning from SSLv3 through TLSv1.3.

Supported Protocols

  • SSLv3
  • TLSv1.0
  • TLSv1.2
  • TLSv1.3

Cipher Suites by Protocol

SSLv3

The service supports 20 ciphers including ADH-AES256-SHA, AES256-SHA, CAMELLIA256-SHA, and variants using PSK (Pre-Shared Key) authentication.

TLSv1.0

This protocol includes 27 cipher options, featuring ECDHE (Elliptic Curve Diffie-Hellman Ephemeral) combinations with both AES and CAMELLIA algorithms, plus PSK variants.

TLSv1.2

The most extensive support includes approximately 56 ciphers featuring:

  • ECDHE with GCM (Galois/Counter Mode) for authenticated encryption
  • CHACHA20-POLY1305 modern cipher suite
  • CCM (Counter with CBC-MAC) variants
  • ARIA algorithm support
  • AES-GCM combinations

TLSv1.3

The latest protocol version includes three modern cipher suites:

  • TLS_AES_256_GCM_SHA384
  • TLS_CHACHA20_POLY1305_SHA256
  • TLS_AES_128_GCM_SHA256

Connection

This extensive cipher support ensures compatibility with servers using various encryption standards while maintaining security across connection types.

Always use STARTTLS (port 587) or SSL/TLS (port 465) when connecting to smtp.improvmx.com.

Still have questions? Feel free to reach out to our support team!