Networking Protocols

HTTP - Hyper Text Transfer Protocol

The world wide Web is driven by two fundamental technologies: HTTP and HTML. HTTP is the Hypertext Transfer Protocol that controls how Web servers and Web browsers communicate with each other. HTML is the Hypertext Markup Language that defines the structure and contents of a Web page. To retrieve a Web page, the browser sends a request to a Web server using HTTP. On receiving the request, the server interprets it, sometimes using a CGI script (see CGI - Common Gateway Interface), and sends back data. This data can be just about anything, including HTML, text, images, programs, and sound.

SMTP - Simple Mail Transport Protocol

The Simple Mail Transport Protocol (SMTP) controls the transfer of email messages on the Internet. SMTP defines the interaction between Internet hosts that participate in forwarding email from a sender to its destination.

POP - Post Office Protocol

The Post Office Protocol (POP) allows you to fetch email that is waiting in a mail server mailbox. POP defines a number of operations for how to access and store email on your server.

FTP - File Transfer Protocol

The File Transfer Protocol (FTP) is used widely on the Internet for transferring files to and from a remote host. FTP is commonly used for uploading pages to a Web site and for providing online file archives.

CGI - Common Gateway Interface

The common gateway interface is used with many Web servers to provide processing beyond the normal HTTP Web interface. CGI requests are submitted from Web browsers to Web servers. When a server receives a CGI request, it typically executes a script to process the request and return a result to the browser. These CGI scripts can be written in a variety of languages, and REBOL provides one of the easier ways of handling CGI.

TCP / IP - Transmission Control Protocol / Internet Protocol

Transmission Control Protocol (TCP) and Internet Protocol (IP) are the core protocols of the Internet Protocol Suite, therefore the entire suite is commonly referred to as TCP/IP.
TCP provides the service of exchanging data directly between two network hosts, whereas IP handles addressing and routing message across one or more networks. In particular, TCP provides reliable, ordered delivery of a stream of bytes from a program on one computer to another program on another computer.

UDP - User Datagram Protocol

The User Datagram Protocol is another transport layer protocol that provides a connectionless method of communicating between machines. It allows you to send datagrams, packets, between machines. The operation of UDP is much different than TCP. UDP is simpler, but it is essentially unreliable. There is no guarantee that a packet will ever reach its destination. In addition, UDP has no flow control. If you send messages too quickly, packets may be lost.