Protocol
A protocol is a set of predefined rules that govern how two or more processes communicate and interact to exchange data. Protocols are considered as the building blocks of network communication. Computer protocols are used by communicating devices and software services to format data in a way that all participants understand. It provides a context in which to interpret communicated information.
Primary Protocols
NetBEUI: NetBIOS Extended User Interface (NetBEUI) is a Microsoft proprietary non-routable protocol. It is usually used in single LANs comprising one to two hundred clients. NetBEUI was developed by IBM for its LAN Manager product and has been adopted by Microsoft for its Windows NT, LAN Manager, and Windows for Workgroups products.
IPX/SPX: Internet Packet Exchange/Sequenced Packet Exchange (IPX/SPX) is a protocol used by Novell NetWare clients to connect to NetWare server. IPX/SPX is a routable protocol. It is supported by Microsoft operating systems. IPX/SPX can be used for both large and small networks. The Internet does not use this protocol.
NWLink: NWLink is a standard network protocol that supports routing. It is the Microsoft equivalent of Novell's IPX/SPX protocol. NWLink provides connectivity between Windows and Novell computers. It can support NetWare client/server applications, where NetWare-aware Sockets-based applications communicate with IPX/SPX Sockets-based applications.
AppleTalk: AppleTalk is Apple's proprietary protocol suite for Macintosh network communications. It uses services built into the operating system to provide a multilayer, peer-to-peer architecture. It has very limited support on other platforms. Windows 2000 versions support the AppleTalk protocol.
TCP/IP: Transmission Control Protocol/Internet Protocol (TCP/IP) is a suite of standard protocols that govern how data passes between networks. It can be used to provide communication between the basic operating systems, on local and wide-area networks (WANs). TCP/IP is considered as the primary protocol suite for the Internet and the World Wide Web.
The description of the primary protocols in the suite is as follows:
| Protocol Name | Description |
| IP | Internet Protocol (IP) is a connectionless network-layer protocol that is the primary carrier of data on a TCP/IP network. |
| TCP | Transmission Control Protocol (TCP) is a reliable, connection-oriented protocol operating at the transport layer. The protocol can transmit large amounts of data. Application-layer protocols such as HTTP and FTP utilize the services of TCP to transfer files between clients and servers. |
| UDP | User Datagram Protocol (UDP) is a connectionless, unreliable transport-layer protocol. UDP is used primarily for brief exchange of requests and replies. |
| Telnet | Telnet is a protocol that enables an Internet user to log onto and enter commands on a remote computer linked to the Internet, as if the user were using a text-based terminal directly attached to that computer. |
| FTP | File Transfer Protocol (FTP) is a primary protocol of the TCP/IP protocol suite, used to transfer text and binary files between computers over a TCP/IP network. |
| SMTP | Simple Mail Transfer Protocol (SMTP) is used for transferring or sending e-mail messages between servers. |
PPP: Point-to-Point Protocol (PPP) is
a set of industry-standard framing and authentication protocols included with Windows remote access to ensure interoperability with third-party remote access software. It is a data link-layer protocol designed to create direct connection between two computers, typically using telephone lines.
POP3: Post Office Protocol version 3 (POP3) is a protocol used for retrieving e-mail messages. The POP3 servers allow access to a single Inbox in contrast to IMAP servers that provide access to multiple server-side folders.
IMAP: Internet Message Access Protocol (IMAP) is a protocol for receiving e-mail messages. It allows an e-mail client to access and manipulate a remote e-mail file without downloading it to the local computer. It is used mainly by users who want to read their e-mails from remote locations.
PPTP: Point-to-Point Tunneling Protocol (PPTP) is an encryption protocol used to provide secure, low-cost remote access to corporate networks through public networks such as the Internet. Using PPTP, remote users can use PPP-enabled client computers to dial a local ISP and connect securely to the corporate network through the Internet.
HTTP: Hypertext Transfer Protocol (HTTP) is a client/server TCP/IP protocol used on the World Wide Web (WWW) to display Hypertext Markup Language (HTML) pages. HTTP defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands. For example, when a client application or browser sends a request to the server using HTTP commands, the server responds with a message containing the protocol version, success or failure code, server information, and body content, depending on the request. HTTP uses TCP port 80 as the default port.
HTTPS: Hypertext Transfer Protocol Secure (HTTPS) protocol is a protocol used in the Uniform Resource Locater (URL) address line to connect to a secure site. If a site has been made secure by using the Secure Sockets Layer (SSL), HTTPS (instead of HTTP protocol) should be used as a protocol type in the URL.
