[ Thanks to Lee
Schlesinger for this link. ]
“OpenSSL, the open source toolkit for implementing the Secure
Sockets Layer (SSL) and Transport Layer Security (TLS) protocols,
is an everyday essential for most Linux admins responsible for
secure networking. But OpenSSL includes a wealth of features that
even grizzled veterans may not be familiar with. You can use
OpenSSL to test POP and IMAP servers, and test server connection
speeds, among other interesting tricks.“When you roll out a new mail server, or make changes to an old
one, good old telnet is still the standby for testing unencrypted
POP and IMAP server sessions. But what about servers that use
TLS/SSL encryption?”