>> Just a few more protocols, important numbers.
The next protocol we have is LDAP,
Lightweight Directory Access Protocol.
This is the database format or structure
>> for active directory
>> and any sort of directory services that we use.
>> When you see LDAP,
I want you to think domain controller,
if you're a Windows person,
or a more general term, authentication server.
LDAP is the protocol
>> that allows the structuring of organizations
>> and you can see that it's a hierarchical structure.
>> At the top, we have a root, children and leaps.
In windows at the top,
you have the root, down to domains,
down to organizational units,
then down to groups and users.
But at any rate, it's a structuring of R
>> and network environment
>> that makes it very easy to access information
>> and to retrieve information
>> and to organize our network.
>> LDAP uses port 389 or a secure LDAP uses port 636.
Mentioned a few minutes ago that HTTP is insecure.
What do we do?
>> We can use SSL and TLS to provide security.
>> SSL and TLS uses port 443.
These are not the same protocol.
SSL and TLS are two different protocols
>> but they do both use 443
>> and a lot of ways they operate in a similar fashion.
>> RADIUS stands for Remote
Authentication Dial-In User Services.
We actually talked about
this same idea back with TACACS Plus.
What RADIUS does is allow a centralized location to
configure policies and rules of remote access clients.
For instance, when we say remote access clients,
we're talking about clients that access the network
without being physically plugged into the network.
Wi-Fi clients style up,
which I know we scoff at dial-up because we don't think
of dusting off our modems to connect to our networks.
But dial-up still exist in particular environments.
Plus we have to keep in mind that not
everywhere has high-speed access.
Remote access services and dial-up are still around.
We also think about VPN clients
connecting to VPN servers.
Over on the left where you see supplicants,
supplicant is the device that initiates the connection.
It's the remote device that wants to
connect to the local area network.
Traditionally, the supplicants have to
connect to two devices called authenticators.
My Wi-Fi device connects to an access point,
my dial-up client connects to a remote access server,
my VPN client to a VPN server and traditionally,
what has happened is the policy decisions
>> were configured and made on these authenticators.
>> What I mean by that is
>> if I want to set up very strict requirements
>> for who can access the network wirelessly, what time,
what type of connection,
what location, or any set of requirements,
what I would have to do is go to those access points
>> and configure the rules, the policies.
>> Same thing if I have multiple dial-up servers
or remote access servers,
I'd have to configure policy on
>> each of those servers, same thing with VPN.
>> What I have is a really distributed environment
where I would have to walk around
from access point to access point and configure policy.
Or instead, I can configure those devices with
authenticators to forward the authentication requests
to a RADIUS server.
I would configure policy just on that RADIUS server,
that's exactly what TACACS Plus was for.
There's also a protocol that's similar called diameter.
Diameter never really took off,
but it's purpose was to replace RADIUS
as diameter as twice the RADIUS.
RADIUS is all about central authentication for
remote access services and it uses port 1812 and 1813,
and it works very comparably to TACACS Plus.
Remote Desktop Protocol, RDP.
This is a very dangerous protocol
from a security perspective
because what RDP allows you
>> to do is access another user's system.
>> You can perform operations
>> just as if you're sitting in front of that system.
>> In some ways, that's very helpful.
Because if you need help doing
some administrative type task
and you don't know how to add a printer,
then I can RDP into your system,
you can watch me add a printer and that'll
make it easier for you next time.
But of course, with any remote access,
you got to be very careful,
cautious, and limited where we allow RDP.
I can't think of a lot of reasons that I'm going to allow
unfettered RDP access from outside the network in,
probably not a good idea.
RDP uses port 3389.
Now, I'm not going to tell you these are
all the port numbers you could conceivably see.
But if I were studying for
this exam and for those of you who are
coming down the line and looking
forward to the security plus exam,
these are the protocols that I'd be sure to know.
Have a brief understanding that this level,
you don't need to be in depth with any of
these particles but I would encourage you as we continue,
you'll want to go a bit deeper
and we'll cover those throughout the class.
Now, in these key takeaways,
there are few protocols that we have not discussed.
I request that you focus on the ones we've
covered as far as understanding them in
more depth but it doesn't hurt
to know one or two additional protocols.
There's one here for NetBIOS
and Network News Transfer Protocol.
The best way to memorize these ports
>> is to get a deck of flashcards
>> and put HTTP on the front and on the back port 80.
>> If we take the time to do that,
then I think you'll find that
>> you can memorize the ports fairly quickly
>> and it won't be too challenging.
>> Like I said, these little wrap-up ports
>> give you a couple more,
>> but I would focus on the port numbers
>> that I've given you.
>> With this being one of those lists that
out of everything that I could possibly throw at you,
one of these port numbers could pop up,
but please focus on the ones that I've provided.