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!

Enjoy The TCP/IP Guide? Get the complete PDF!
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 Control Message Protocol (ICMP/ICMPv4 and ICMPv6)
                9  ICMP Message Types and Formats
                     9  ICMP Version 6 (ICMPv6) Informational Message Types and Formats

Previous Topic/Section
ICMPv6 Echo Request and Echo Reply Messages
Previous Page
Pages in Current Topic/Section
12
3
Next Page
ICMPv6 Neighbor Advertisement and Neighbor Solicitation Messages
Next Topic/Section

ICMPv6 Router Advertisement and Router Solicitation Messages
(Page 3 of 3)

ICMPv6 Router Solicitation Message Format

The format of an ICMPv6 Router Solicitation message is as shown Table 110 and Figure 159.


Figure 159: ICMPv6 Router Solicitation Message Format

 



Table 110: ICMPv6 Router Solicitation Message Format

Field Name

Size (bytes)

Description

Type

1

Type: Identifies the ICMPv6 message type; for Router Solicitation messages the value is 133.

Code

1

Code: Not used; set to 0.

Checksum

2

Checksum: 16-bit checksum field for the ICMP header, as described in the topic on the ICMP common message format.

Reserved

4

Reserved: 4 reserved bytes set to 0.

Options

Variable

Options: If the device sending the Router Solicitation knows its layer two address, it should be included in a Source Link-Layer Address option. Option formats are described in a separate topic.


Addressing of Router Advertisement and Router Solicitation Messages

Router Solicitation messages are normally sent to the IPv6 “all routers” multicast address; this is the most efficient method since routers are required to subscribe to this multicast address while hosts will ignore it. A routine (unsolicited) Router Advertisement is sent to all devices using the “all nodes” multicast address for the local network. A Router Advertisement that is sent in response to a Router Solicitation goes unicast back to the device that sent the solicitation.

Key Concept: ICMPv6 Router Advertisement messages are sent regularly by IPv6 routers to inform hosts of their presence and characteristics, and to provide hosts with parameters they need to function properly on the local network. A host that wants to find out immediately what routers are present may send a Router Solicitation, which will prompt listening routers to send out Router Advertisements.



Previous Topic/Section
ICMPv6 Echo Request and Echo Reply Messages
Previous Page
Pages in Current Topic/Section
12
3
Next Page
ICMPv6 Neighbor Advertisement and Neighbor Solicitation Messages
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.