Posts Tagged ‘domain’

X-FRAME-OPTIONS HTTP Header

Wednesday, September 8th, 2010

Added in MSIE8 and Mozilla Firefox 3.6.9, Apple Safari 4, IE8, and Google Chrome 2 are several mechanisms to defend against cross-domain forgeries.

Supported Values:
X-FRAME-OPTIONS: DENY
X-FRAME-OPTIONS: SAMEORIGIN

You can explicitly set this value for ApacheHTTP in the httpd.conf file, your .htaccess files or code it into the page(s) by the application itself.

Dotless IP Address

Friday, December 11th, 2009

This is a concept I had forgotten about until recently, it can often serve as a simple means of code obfuscation and is also sometimes referred to as “Decimal Address”.

Some background:

  • DNS is used to convert a URL/domain name into an IP address that is used to contact the remote machine.
    EXAMPLES:
    localhost = 127.0.0.7
    giantgeek.com = 99.138.127.198
  • IP addresses (as IPv4) are represented as groups of 4 hexadecimal or decimal octets.
  • Those numbers can be plugged into a simple formula to be represented as a single large integer.

As such, you can use the following as equivalents:

  • http://localhost
  • http://127.0.0.1
  • http://2130706433

REFERENCES:

What is a SLD (Second Level Domain)?

Friday, July 13th, 2007

I just wrote about the TLD, so this naturally follows:

A SLD includes the TLD name and further identifies the owning organization of a URL.

Second-level domains can be divided into further levels. These subdomains sometimes represent different computers within an organization, but are many times the same machine with different aliases.

Examples:

www.giantgeek.com
mail.giantgeek.com

TLD =  .com
SLD = giantgeek.com
Subdomains = www.gianteek.com & mail.giantgeek.com

NOTE: Refer to HTTP/1.1 for details on how IP addresses, routing and webservers are impacted by this.

Interesting enough, some one character SLD’s do exist,  x.com for example.

References:

Cheers!

What is a TLD (Top Level Domain)?

Friday, July 13th, 2007

I occasionally get this question, as many technical people don’t fully understand it.

A TLD is ‘actually” the last section of a URL (owned by the domain registrars themselves).

Examples:

  • .com
  • .net
  • .org
  • .us (and other 2 digit country codes)

You can find a full list of TLD’s here:

Various other TLD’s have been proposed through the years, here are a few common ones (that are in various states of approval or implementation):

  • .museum
  • .info
  • .xxx
  • .biz
  • .mobi

References:

Cheers!