February 2000
Intermediate to advanced
464 pages
15h 57m
English
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Application Protocols
A variety of application protocols exist that provide standardized mechanisms for the exchange of information across vendor bounds. Among these are file transfer protocols such as FTP, Gopher, and HTTP; groupware and electronic mail services such as SMTP, POP3, IMAP4, and NNTP; and protocols for locating network resources such as DNS, Finger, and LDAP, among many others.
It’s important to realize that client applications generally consist of two distinct components: the application protocol (such as HTTP or POP3), and an end-user interface that displays information. For example, a web browser uses HTTP (the protocol) to retrieve HTML and GIFs from a web server, but the code for displaying that data is a separate service that is not covered by the protocol specification.
For more on the common application protocols found on the Internet today, refer to the book Internet Application Protocols, which covers most of these protocols.