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!

Searchable, convenient, complete TCP/IP information.
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  TCP/IP IPv6 Neighbor Discovery Protocol (ND)

Previous Topic/Section
IPv6 ND Overview, History, Motivation and Standards
Previous Page
Pages in Current Topic/Section
1
2
3
Next Page
IPv6 ND Functions Compared to Equivalent IPv4 Functions
Next Topic/Section

IPv6 ND General Operational Overview: ND Functions, Functional Groups and Message Types
(Page 2 of 3)

Host-Router Discovery Functions

One of the two main groups of functions in ND are those that facilitate the discovery of local routers and the exchange of information between them and hosts. This includes four specific functions:

  • Router Discovery: This is the core function of this group: the method by which hosts locate routers on their local network.

  • Prefix Discovery: Closely related to the process of router discovery is prefix discovery. Recall that the term “prefix” refers to the network portion of an IP address. Hosts use this function to determine what network they are on, which in turn tells them how to differentiate between local and distant destinations and whether to attempt direct or indirect delivery of datagrams.

  • Parameter Discovery: Also closely related to router discovery, this is the method by which a host learns important parameters about the local network and/or routers, such as the maximum transmission unit of the local link.

  • Address Autoconfiguration: Hosts in IPv6 are designed to be able to automatically configure themselves, but this requires information that is normally provided by a router.
Host-Host Communication Functions

The other main group of functions is that associated with information determination and communication directly between nodes, usually hosts. Some of these functions can be performed between hosts and routers, but this group is not specifically related to router discovery; it includes:

  • Address Resolution: The process by which a device determines the layer two address of another device on the local network from that device's layer three (IP) address. This is the job performed by ARP in IP version 4.

  • Next-Hop Determination: The method for looking at an IP datagram's destination address and determining where it should next be sent.

  • Neighbor Unreachability Detection: The process of determining whether or not a neighbor device can be directly contacted.

  • Duplicate Address Detection: Determining if an address that a device wishes to use already exists on the network.
Redirect Function

The last functional group contains just one function: Redirect. The technique whereby a router informs a host of a better next-hop node to use for a particular destination.

Key Concept: The Neighbor Discovery protocol encompasses nine individual functions, many of which are related to each other. They are organized into three functional groups: host-router discovery functions, host-host communication functions, and the redirect function.



Previous Topic/Section
IPv6 ND Overview, History, Motivation and Standards
Previous Page
Pages in Current Topic/Section
1
2
3
Next Page
IPv6 ND Functions Compared to Equivalent IPv4 Functions
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.