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 Network Interface Layer (OSI Data Link Layer) Protocols
           9  TCP/IP Serial Line Internet Protocol (SLIP) and Point-to-Point Protocol (PPP)
                9  Point-to-Point Protocol (PPP)
                     9  PPP Protocol Frame Formats

Previous Topic/Section
PPP General Frame Format
Previous Page
Pages in Current Topic/Section
123
4
Next Page
PPP Link Control Protocol (LCP) Frame Formats
Next Topic/Section

PPP General Control Protocol Frame Format and Option Format
(Page 4 of 4)

Summary of PPP Control Message Formatting

Well now… My intention in this topic was to show you the general format used for the different control protocols since they are so similar and I don't have the time or space to describe each protocol's frames individually. I concede that this may have ended up being more confusing than enlightening, since it may be difficult to see how PPP moves from the general to the specific in its formatting. If it will help, here's a quick summary:

  1. The PPP general frame format is used for all frames, including all control frames. Its Information field contains the payload, which carries the entire control message within it for control frames.

  2. The control frame is structured using the general format I gave at the start of this topic. The Code value indicates the type of control frame for each control protocol. The Data field is variable in length, and contains data for that control frame, which in some cases may include one or more configuration options.

  3. For configuration control frames like Configure-Request and Configure-Ack, the Data field contains an encapsulated set of options using the general structure in the second table in this topic. Each option has its own Data subfield that contains data specific to that option.

To help make this more clear, the next two topics provide more specific examples of frame formats for LCP and the authentication protocols.


Previous Topic/Section
PPP General Frame Format
Previous Page
Pages in Current Topic/Section
123
4
Next Page
PPP Link Control Protocol (LCP) Frame Formats
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.