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!

Get The TCP/IP Guide for your own computer.
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 4 (IP, IPv4)

Previous Topic/Section
IP Message Reassembly Process
Previous Page
Pages in Current Topic/Section
1
Next Page
IP Datagram Direct Delivery and Indirect Delivery (Routing)
Next Topic/Section

IP Datagram Delivery and Routing

The essential functions of IP datagram encapsulation and addressing are sometimes compared to putting a letter in an envelope and then writing the address of the recipient on it. Once our IP datagram “envelope” is filled and labelled, it is ready to go, but it's still sitting on our desk. The last of the main functions of IP is to get the envelope from us to our intended recipient. This is the process of datagram delivery. When the recipient is not on our local network, this delivery requires that the datagram be routed from our network to the one where the destination resides.

In this section I discuss some of the particulars of how IP routes datagrams over an internetwork. I begin with an overview of the process and contrast direct and indirect delivery of data between devices. I discuss the main method used to route datagrams over the internet, and also explain briefly how IP routing tables are built and maintained. I discuss how the move from “classful” to classless addressing using CIDR impacted routing.

Related Information: Note that this section is brief and focuses mainly on routing issues that are directly related to how IP works. Routing is a complex and important topic in networking, and you'll find much more information about it in the section that discusses TCP/IP routing/gateway protocols. I have tried not to duplicate that section by putting too much information about the process of routing here.


Quick navigation to subsections and regular topics in this section



Previous Topic/Section
IP Message Reassembly Process
Previous Page
Pages in Current Topic/Section
1
Next Page
IP Datagram Direct Delivery and Indirect Delivery (Routing)
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.