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HTTP Properties
- A comprehensive addressing scheme
The HTTP protocol uses the concept of reference provided by
the Universal Resource Identifier (URI) as a location (URL)
or name (URN),
for indicating the resource on which a method is to be applied.
When an HTML hyperlink is
composed, the URL (Uniform Resource Locator) is of the general
form http://host:port-number/path/file.html.
More generally, a URL reference is of the type
service://host/file.file-extension and in this way, the
HTTP protocol can subsume the more basic Internet services.
- Client-Server Architecture
The HTTP protocol is based on a request/response paradigm.
The communication generally takes place over a TCP/IP connection
on the Internet.
The default port is 80, but other ports can be used.
This does not preclude the HTTP/1.0 protocol from being implemented
on top of any other protocol on the Internet,
so long as reliability can be guaranteed.
- The HTTP protocol is connectionless and stateless
After the server
has responded to the client's request, the connection
between client and server is dropped and forgotten. There is no
"memory" between client connections. The pure HTTP server
implementation treats every request as
if it was brand-new, i.e. without context.
- An extensible and open representation for data types
HTTP uses Internet Media Types
(formerly referred to as MIME Content-Types)
to provide open and extensible data typing and type negotiation.
When the HTTP Server transmits information back to the client,
it includes a MIME-like (Multipart Internet Mail Extension)
header to inform the client what kind of data follows the header.
Translation then depends on the client possessing the
appropriate utility (image viewer, movie player, etc.)
corresponding to that data type.
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