Search results
Results from the WOW.Com Content Network
The port numbers in the range from 0 to 1023 (0 to 2 10 − 1) are the well-known ports or system ports. [3] They are used by system processes that provide widely used types of network services. On Unix-like operating systems, a process must execute with superuser privileges to be able to bind a network socket to an IP address using one of the ...
Only servers listening on port 587, or private servers, should be configured that way, not a Message eXchange (MX). However, the historical trait that SMTP is not authenticated by default results in a different behavior with regard to access protocols, in some cases; for example, when using AUTH EXTERNAL after STARTTLS.
Several protocols use a command named "STARTTLS" for this purpose. It is a form of opportunistic encryption and is primarily intended as a countermeasure to passive monitoring . The STARTTLS command for IMAP and POP3 is defined in RFC 2595 , for SMTP in RFC 3207 , for XMPP in RFC 6120 and for NNTP in RFC 4642 .
Transport Layer Security (TLS) is a cryptographic protocol designed to provide communications security over a computer network, such as the Internet.The protocol is widely used in applications such as email, instant messaging, and voice over IP, but its use in securing HTTPS remains the most publicly visible.
The RFC specifies this code should be returned by teapots requested to brew coffee. [18] This HTTP status is used as an Easter egg in some websites, such as Google.com's "I'm a teapot" easter egg. [19] [20] [21] Sometimes, this status code is also used as a response to a blocked request, instead of the more appropriate 403 Forbidden. [22] [23]
In early 1997, the Internet Assigned Numbers Authority registered port 465 for smtps. [1] Late 1998 this was revoked when STARTTLS was standardized. [2] With STARTTLS, the same port can be used with or without TLS. The use of well-known ports for mail exchanges communicating with SMTP was discussed in particular at the time. [3]
This is a list of the IP protocol numbers found in the field Protocol of the IPv4 header and the Next Header field of the IPv6 header. It is an identifier for the encapsulated protocol and determines the layout of the data that immediately follows the header. Both fields are eight bits wide.
Email is submitted by a mail client (mail user agent, MUA) to a mail server (mail submission agent, MSA) using SMTP on TCP port 587. Most mailbox providers still allow submission on traditional port 25. The MSA delivers the mail to its mail transfer agent (MTA). Often, these two agents are instances of the same software launched with different ...