This category is for the protocols that are used in the Internet protocol suite, commonly known as the TCP/IP model, also known as the DoD model.
Submitted sites should be related to the Internet protocols, not the software or servers that use them. Software that uses the protocols should be submitted to the appropriate subcategory in Computers/Software/Internet (ex. Computers/Software/Internet/Clients/Chat/IRC).
CIFS stands for Common Internet File System. It is also known as Server Message Block (SMB). It is an application layer protocol.
DANE stands for DNS-based Authentication of Named Entities. It is a protocol to allow X.509 certificates, commonly used for Transport Layer Security (TLS), to be bound to DNS names using Domain Name System Security Extensions (DNSSEC).
DHCP stands for Dynamic Host Configuration Protocol. It is an application layer protocol.

Every computer on a TCP/IP network must be given a unique computer name and IP address. DHCP specifies methods for dynamic configuration of computers on TCP/IP networks. DHCP is designed to simplify and reduce the configuration and administration of computers on the network.
The main category is for general information about the protocol. Sites about implementations of the standard should go to the Implementations subcategory.

DNS

DNS stands for Domain Name System. It is an application layer protocol.

DNS is a distributed Internet directory service. A network of DNS servers respond to requests to translate between domain names (such as dmoz.org) and IP, Internet Protocol, numeric addresses (such as 207.200.81.139) for URLs and email delivery. Most Internet services rely on DNS to work.

Please do not submit sites that primarily host dynamic DNS -- those should go to Top: Computers: Software: Internet: Servers: Address Management: Dynamic DNS Services.

FTP

FTP stands for File Transfer Protocol. It is an application layer protocol. FTP can be combined with cryptographic protocols. Information related to such protocols (Explicit FTPS, Implicit FTPS, FTP over SSH) should also be submitted to this category.
Bear in mind that SSH File Transfer Protocol (also known as Secure File Transfer Protocol, Secure FTP, or SFTP) is not an extension of FTP, but of SSH.
From The Free On-line Dictionary of Computing (05 Sep 00): A popular distributed document retrieval system which started as a Campus Wide Information System at the University of Minnesota. Many hosts on the Internet now run Gopher servers which provide a menu of documents. A document may be a plain text file, sound, image, submenu or other Gopher object type. It may be stored on another host or may provide the ability to search through certain files for a given string. From Jargon File (4.2.0, 31 Jan 2000): gopher n. A type of Internet service first floated around 1991 and obsolesced around 1995 by the World Wide Web. Gopher presents a menuing interface to a tree or graph of links; the links can be to documents, runnable programs, or other gopher menus arbitrarily far across the net. Some claim that the gopher software, which was originally developed at the University of Minnesota, was named after the Minnesota Gophers (a sports team). Others claim the word derives from American slang `gofer' (from "go for", dialectal "go fer"), one whose job is to run and fetch things. Finally, observe that gophers dig long tunnels, and the idea of tunneling through the net to find information was a defining metaphor for the developers. Probably all three things were true, but with the first two coming first and the gopher-tunnel metaphor serendipitously adding flavor and impetus to the project as it developed out of its concept stage.
If the site has valuable information about the Gopher protocol, this category is the right place, no matter if it is a Gopher or a Web site. However, the mere fact that a site be on Gopher is not a good reason to submit it here. Basically, a Gopher site with valuable information on a given topic should be submitted to the category covering this topic.
HTTP stands for Hypertext Transfer Protocol. It is an application layer protocol. HTTP can be combined with cryptographic protocols. Information related to such protocols (HTTPS) should also be submitted to this category.

IP

IP stands for Internet Protocol. It is an internet layer protocol.

IP is the standard method for transporting data between computers on the Internet. IP encodes data in the form of packets, a linear sequence of bytes of a known length. Each packet contains a header section at the beginning that includes the addresses of the source and destination computer, as well as error detection data.
This section accepts sites and pages that discuss IP (IPv4) specifically. Sites that discuss IPv6 should be submitted to

Computers: Internet: Protocols: IP: IPng

and sites that discuss TCP/IP should be submitted to

Computers: Internet: Protocols.

IRC

IRC stands for Internet Relay Chat. It is an application layer protocol.
LDAP stands for Lightweight Directory Access Protocol. It is an application layer protocol.
Electronic mail protocols are application layer protocols. Mail servers use SMTP to send and receive mail messages. User-level client mail applications use SMTP for sending messages to a mail server for relaying and use another protocol to receive messages: POP, IMAP or a proprietary system such as Microsoft Exchange or Lotus Notes/Domino. Electronic mail protocols are often combined with cryptographic protocols. Information related to such protocols (IMAPS, STARTTLS etc.) should also be submitted to this category.
This is a collection of links to pages which explain various protocols related to email handling. If you are looking for mail software, go look in Computers:Software. This is for people interested in understanding how the mail system itself works.
NNTP stands for Network News Transfer Protocol. It is an application layer protocol.

NNTP is used for transporting Usenet news articles between news servers and for reading and posting articles by end user client applications.

NTP

NTP stands for Network Time Protocol. It is an application layer protocol.

Network Time Protocol (NTP), discussed in RFCs 1305 and 2030, provides a distributed mechanism for synchronizing the system clocks on computers across a network.
Sites for NTP client software should be submitted to Computers/Software/Internet/Clients/Time while sites describing NTP server software or sites from companies which provide equipment to support the protocol should be submitted to Computers/Software/Internet/Servers/Time. Sites which discuss other aspects of time and sites which display the current time from the web should be placed in Reference/Time.

PPP

PPP stands for Point-to-Point Protocol. It is a data link protocol.
If you want to add an ISP that provides PPP services to the Directory, you should submit it under Computers: Internet: Internet Service Providers.
RTSP stands for Real Time Streaming Protocol. It is an application layer protocol.
The main category is for general information about the protocol. Sites about implementations of the standard should go to the Implementations subcategory.
RWhois stands for Referral Whois. It is an application layer protocol.

RWhois is a Directory Services protocol which extends and enhances the Whois concept in a hierarchical and scalable fashion. It focuses on the distribution of "network objects" -- the data representing Internet resources or people -- and uses the inherently hierarchical nature of these network objects (domain names, Internet Protocol (IP) networks, email addresses) to more accurately discover the requested information.

SIP

SIP stands for Session Initiation Protocol. It is an application layer protocol.

SIP is for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls, instant messaging, multimedia conferences, and multimedia distribution.
Please only submit Voice over IP websites that specifically, or primarily, relate to the SIP protocol.
SNMP stands for Simple Network Management Protocol. It is an application layer protocol.

SSH

SSH stands for Secure Shell. It is an application layer protocol.
Since SSH File Transfer Protocol (also known as Secure File Transfer Protocol, Secure FTP, or SFTP) is an SSH, documents relating to it should also be submitted to this category.
Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL), are cryptographic protocols that provide communication security over the Internet. They are used with application layer protocols like HTTP, FTP, POP3, IMAP.
Telnet is an application layer protocol.

Official documents and user-friendly guides are both welcome.
Telnet clients should be submitted to Computers/Software/Internet/Clients/Telnet/ Telnet servers should be submitted to Computers/Software/Internet/Servers/Telnet/
TFTP stands for Trivial File Transfer Protocol. It is an application layer protocol.

TFTP is a very simple file transfer protocol, with the functionality of a very basic form of FTP. It is used primarily for transferring files to and from network equipment such as a router, switch or hub thanks to its very small memory footprint.
This category is for the transport layer in the Internet protocol suite, commonly known as the TCP/IP model. It is described in RFC 1122. The transport layer handles host-to-host communication.
WHOIS comes from the phrase 'who is'. It is an application layer protocol.
XMPP stands for Extensible Messaging and Presence Protocol. It is an application layer protocol.