Please Whitelist This Site?
I know everyone hates ads. But please understand that I am providing premium content for free that takes hundreds of hours of time to research and write. I don't want to go to a pay-only model like some sites, but when more and more people block ads, I end up working for free. And I have a family to support, just like you. :)
If you like The TCP/IP Guide, please consider the download version. It's priced very economically and you can read all of it in a convenient format without ads.
If you want to use this site for free, I'd be grateful if you could add the site to the whitelist for Adblock. To do so, just open the Adblock menu and select "Disable on tcpipguide.com". Or go to the Tools menu and select "Adblock Plus Preferences...". Then click "Add Filter..." at the bottom, and add this string: "@@||tcpipguide.com^$document". Then just click OK.
Thanks for your understanding!
Sincerely, Charles Kozierok
Author and Publisher, The TCP/IP Guide
NOTE: Using software to mass-download the site degrades the server and is prohibited.
If you want to read The TCP/IP Guide offline, please consider licensing it. Thank you.
World Wide Web Addressing: HTTP Uniform Resource Locators (URLs)
(Page 2 of 3)
HTTP URL Syntax
HTTP URLs may be absolute
or relative. Absolute URLs are usually
used for hyperlinks from one Web site to another, or by users requesting
a new document without any prior context. Absolute HTTP URLs are based
on the following common
Internet URL syntax:
For the Web, the scheme is http:
and the semantics of the different URL elements is defined to have meanings
that are relevant to the Web. The general structure of an HTTP URL is
The following shows how these syntactic
elements are specifically defined for HTTP absolute URLs:
- <user> and <password>: Optional
authentication information, for resources located on password-protected
servers. This construct is rarely used in practice and so most people
don't realize it is an option; it has thus become a target of abuse
by con artists who use it to obscure
- <host>: The host name of the Web
server upon which the resource is located. This is usually a fully-qualified
DNS domain name, but may also be an IP
- <port>: The TCP
port number to use for connecting to the
Web server. This defaults to 80 for HTTP and is usually omitted. Rarely,
you may see some other port number used, sometimes to allow two copies
of Web server software devoted to different uses on the same IP address;
port 8080 is especially common as an alternative.
- <url-path>: The path pointing to
the specific resource to be retrieved using HTTP. This is usually a
full directory path expressing the sequence of directories to be traversed
from the root directory to the place where the resource is located,
and then the resource's name. Its important to remember that the
path is case-sensitive, even though DNS domain names are not.
- <query>: An optional query or other
information to be passed to the Web server. This feature is commonly
used to implement interactive functions, because the query value can
be specified by the user and then be passed from the Web browser to
the Web server. The alternative method is by using the HTTP POST method.
- <bookmark>: Identifies a particular
location within an HTML
document. This is commonly used in very
large HTML documents to allow a user to click a hyperlink and scroll
to a particular place in the document. See the example in the previous
topic (near the end of Table 273).
Although the URL syntax for the Web
is quite rich and potentially complex, most Web URLs are
actually quite short. The vast majority of these components are omitted,
especially the user, password, port and bookmark elements; queries are
also used only for special purposes. This leaves the more simplified
form you will usually encounter for URLs:
|If you find The TCP/IP Guide useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider purchasing a download license of The TCP/IP Guide. Thanks for your support!|
Table Of Contents - Contact Us
The TCP/IP Guide (http://www.TCPIPGuide.com)
Version 3.0 - Version Date: September 20, 2005
© Copyright 2001-2005 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.