These changes cause narrowing of the lumbar spinal canal which is known as spinal stenosis. Spinal stenosis is like the lime build-up on the inside of a garden hose. Over time, it narrows the diameter of the hose, just as spinal stenosis narrows the spinal canal.
SMTP Protocol: The SMTP (Simple Mail Transfer Protocol) protocol is used by the Mail Transfer Agent (MTA) to deliver your eMail to the recipient's mail server. The SMTP protocol can only be used to send emails, not to receive them.
When POP3 clients send messages, the Exchange Server computer is communicating with an SMTP (Simple Mail Transfer Protocol) host. This requires access to TCP port 25. The Internet Mail Connector and the Internet Mail Service use TCP port 25 for inbound SMTP messages as defined by RFC-821.or the LDAP client to connect to the Exchange Server computer, the ports that need to be configured on the firewall are based purely on the authentication method in use. With Basic authentication, the Exchange Server computer listens on port 389.