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.

The Book is Here... and Now On Sale!

Read offline with no ads or diagram watermarks!
The TCP/IP Guide

Custom Search







Table Of Contents  The TCP/IP Guide
 9  TCP/IP Lower-Layer (Interface, Internet and Transport) Protocols (OSI Layers 2, 3 and 4)
      9  TCP/IP Internet Layer (OSI Network Layer) Protocols
           9  Internet Protocol (IP/IPv4, IPng/IPv6) and IP-Related Protocols (IP NAT, IPSec, Mobile IP)
                9  Internet Protocol Version 6 (IPv6) / IP Next Generation (IPng)
                     9  IPv6 Addressing

Previous Topic/Section
IPv6 Address Size and Address Space
Previous Page
Pages in Current Topic/Section
1
2
34
Next Page
IPv6 Address Space Allocation
Next Topic/Section

IPv6 Address and Address Notation and Prefix Representation
(Page 2 of 4)

IPv6 Address Hexadecimal Notation

To make addresses shorter, the decision was made in IPv6 to change the primary method of expressing addresses to use hexadecimal instead of decimal. The advantage of this is that it requires fewer characters to represent an address, and that converting from hex to binary and back again is much easier than converting from binary to decimal or vice-versa. The disadvantage is that many people, even computer people, find hexadecimal difficult to comprehend and work with, especially because the notion of 16 values in each digit is a bit strange. (I'm not one of them, but then I'm a geek.)

The hexadecimal notation used for IPv6 addresses is similar to the same method used for IEEE 802 MAC addresses, for technologies like Ethernet. There, 48 bits are represented by six octets, each octet being a hexadecimal number from 0 to FF, separated by a dash or colon, like this:

0A-A7-94-07-CB-D0

Since IPv6 addresses are larger, they are instead grouped into eight 16-bit words, separated by colons, to create what is sometimes called colon hexadecimal notation, again shown in Figure 95. So, the IPv6 address given in the example above would be expressed as:

805B:2D9D:DC28:0000:0000:FC57:D4C8:1FFF

To keep size down, leading zeroes can be suppressed in the notation, so we can immediately reduce this to:

805B:2D9D:DC28:0:0:FC57:D4C8:1FFF

Hmm. Well, it's definitely shorter than dotted decimal, but still not much fun to look at. When you are dealing with numbers this big, there's only so much you can do. This is part of why under IPv6, use of DNS names for hosts becomes much more important than it is in IPv4; who could remember a hex address that long?!


Previous Topic/Section
IPv6 Address Size and Address Space
Previous Page
Pages in Current Topic/Section
1
2
34
Next Page
IPv6 Address Space Allocation
Next Topic/Section

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!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - 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.