MicroNugget: How Kerberos Works in Windows Active Directory | CBT Nuggets

In this video, CBT Nuggets trainer Don Jones walks through how Kerberos works in Active Directory for Windows networks. Learn more about what Kerberos is and how it works with this MicroNugget video from CBT Nuggets.

Kerberos is the native authentication protocol in Active Directory. It's used by Windows networks everywhere. Understanding Active Directory’s more advanced concepts, like delegation, depends on understanding what’s happening under the hood in Kerberos.

Any time authentication is necessary, there are three players: the client making the request, the file server that contains the information, and the KDC or Key Distribution Controller.

In Kerberos, there’s no communication between the file server and the KDC. Because the client takes on the majority of the processing burden. That distributes the authentication workload across the network, securely.

First, the client constructs an authenticator, a package that establishes who the client claims to be, along with the date & time. These authenticators, and the tickets that will follow, have a limited lifespan.

Watch and see how the authenticator gets processed by the KDC, where the ticket-generating ticket (TGT) is stored on the client's machine, and how that TGT grants it access to various resources.

0:25: 3 different parties in authentication
1:25: What happens when a client attempts a secure log-in
3:10: A ticket-granting-ticket (TGT)
5:00: When a ticket is generated by the KDC
5:30: When a client sends a request to a file server
6:50: Overview

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[prafuldalvi]

This is the best explanation. Do not search for any other video.

[fabriceniclot]

the best explanation of kerberos I have ever seen! Thank you.

[michaelboyd]

I must have watched half a dozen different videos over the last two days trying to wrap my head around Kerberos. Not a single other video mentioned the Kerberos Tray, or the CLI tool for the end user. This is BY FAR the BEST explanation I have found, bar none!! Fantastic job!!!

[cbtnuggets]

We are glad you enjoyed this MicroNugget Joe!

[cbtnuggets]

Thanks for the comment. We are glad we could help out.

[flottefar]

Best kerberos ticket explanation. Thanks.
A note: You don't have to download 'kerbtray'. You can just type 'klist' and view cached tickets.
Have fun.

[Just_a_Lad]

Normally the best explanations are the simpliest ones. This video proves it. Thanks.

[lltagged]

Fantastic explanation of Kerberos. Wish Don Jones was still doing IT training.

[tripsd]

Just to clarify all :
When a user logged on, the Kerberos client on the user's workstation accepted the password from the user and converted it into an encryption key by passing the text through a one-way hash function. The resulting hash was the user's master key. The client used this master key to decrypt session keys received from KDC.

[jaredmac]

Man you put this in language that a moderately technical person can understand. Hours of meetings with folks trying to explain it in different ways and you nailed it in 7 minutes.

[joeylee]

Thank you Don and CBT Nuggets! This is definitely one of the best simple high level illustrations of kerberos! Those colored keys really did it for me!

[nukem]

I had Kerberos in my university.. terrible explanations, I was completely lost. Now I went back on it and found your video. I now understand the main ideas way better. Thanks man

[cbtnuggets]

We're glad we could help you understand Kerberos.

[Plonoord]

Nice. When I read this in a book, it didn't make sense to me. I watch this video and it's so much clearer. Kerberos is such a cool concept actually. Thanks.

[Frusciante]

If you can't explain it simply, you don't understand it well enough.
And you sir definitely understand it more than enough :)
Thank you

[anthonybrookes]

Fantastic. Gone from complete confusion to clarity in 7mins. Thank you

[JRavenell]

You really broke down a complex topic into a clear and concise way. THANK YOU!

[richardarmstrong-finnerty]

Excellent. No fluff; just solid information, presented engagingly.

[stevenkim]

if every concept in computing and computer networking was taught as kerberos is explained here, we would all be experts in no time

[miguelnogueira]

After these two years, this video was very educative. I knew nothing about Kerberos and what the heck it was, now I know what it is and how useful it is.