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.
IPSec General Operation, Components and Protocols
(Page 1 of 3)
I have a confession to make: I considered
not writing about IPSec in this Guide. When you find yourself writing
a tome as large as this one, you lose stamina sometimes and there's
this urge to avoid writing about confusing subjects. J
IPSec isn't the only difficult topic in this Guide but it is definitely
a subject that baffles many because it's hard to get your hands around.
Most discussions of it jump straight to describing the mechanisms and
protocols without providing a general description of what it does and
how the pieces fit together. Well, I recognized that IPSec is important
and I don't shy away from a challenge. Thus, here's my attempt to provide
a framework for understanding IPSec's various bits and pieces.
So, what exactly does IPSec do and
how does it do it? In general terms, it provides security services at
the IP layer for other TCP/IP protocols and applications to use. What
this means is that IPSec provides the tools that devices on a TCP/IP
network need in order to communicate securely. When two devices (either
end user hosts or intermediate devices such as routers or firewalls)
want to engage in secure communications, they set up a secure path
between themselves that may traverse across many insecure intermediate
systems. To accomplish this, they must perform (at least) the following
- They must agree on a set of security
protocols to use, so that each one sends data in a format the other
- They must decide on a specific encryption
algorithm to use in encoding data.
- They must exchange keys that are used
to unlock data that has been cryptographically encoded.
- Once this background work is completed,
each device must use the protocols, methods and keys previously agreed
upon to encode data and send it across the network.
|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!|
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.