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Our next feature for RIP here is authentication,
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where RIP supports both clear
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Now, within the scope of the lab exam,
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but if you are doing this in production, obviously, you would
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because if someone is receiving the RIP updates...
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in the RIP header if you're using clear text
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So, with MD-5, we're sending
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which is not reversible.
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So, unless someone is trying to do
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or some sort of collision attack,
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then, it's very unlikely they would know what
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Now, another key point about the
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note that this is not for encryption.
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There is a fundamental difference
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where authentication is just used to validate
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that the update is coming from the correct neighbor.
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It does not mean that the actual information in the
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So, this means that when we look at the
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when we're using MD-5 authentication,
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Someone would still be able to see
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In OSPF, what are the LSAs. In BGP,
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Only in the IPv6 protocols like OSPF version 3 do
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So, with OSPFv3, not only are we doing the
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which would stop anyone in the middle
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from actually seeing what is the
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But assuming that you're using MD-5 to stop them
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Probably doesn't even matter if
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As long as they can't change the routing domain,
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Now, both RIP and EIGRP use the
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Which means that we can define multiple
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as long as they are agreeing on
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So, for MD-5 authentication, if we're
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it means we have to use key
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With clear text, technically,
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But really, there's no reason why you
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At least just for clarity.
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Now, once we create the key
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then, we specify the password.
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And a really important point here
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is that a white space does count as a character.
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So, this means that if we're using
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and we're using the question mark followed by a...
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then, once we hit enter,
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where the carriage return to
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the white space could technically
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So then, once we define the key chain,
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then, we apply it on to the interface level
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and then, we define what type of authentication
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So, let's now say that we're
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routers 1, 4, and 6 on...
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this VLAN 146.
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VLAN 146...
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we'll use MD-5 authentication.
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So, our first step, let's go to router 1.
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And we're going to define the key chain.
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So, we say Key Chain... Give it a name.
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Specify what the key number is.
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And then, what the password is.
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So, we'll say, This is the password. (PASSWORD)
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Then, at the interface level, which in
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We'll say, IP RIP Authentication.
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The mode is either... Or actually,
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The mode is either clear text or MD-5.
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In this case, we'll say MD-5.
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And the IP RIP authentication key chain
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On router 6, we'll do the same thing.
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We'll have Key Chain.
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I'll call it RIP in this case,
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for Key 1 to key string is the password. (PASSWORD)
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At the link level,
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we haven't enabled IP RIP
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IP RIP Authentication Kay Chain is...
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In this case, RIP.
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So now, if we look in the routing table,
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we can assume that the authentication is correct.
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So, if we Show IP Route RIP,
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and we see anything installed via router 1,
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which we can see 6 seconds ago,
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Then, we know the authentication is correct.
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Now, from router 4's perspective,
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router 4 has not configured
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So, if we look at the Debug IP RIP,
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we'll see we are receiving updates
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but we are ignoring it.
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So it says, "For this particular neighbor,
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But the authentication type
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This would then also mean that router 1 and 6,
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So, on router 4, if we configure the
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Key 1...
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And the Key String...
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is the password. (PASSWORD)
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When we apply this at the link level, again, we say
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The authentication key chain's name is RIP.
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If we again look at the Debug IP RIP,
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we should then be installing the
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1 and 6.
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0:08:09
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So, we can see now, we are
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But it still says the authentication is invalid.
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Okay, they're running MD-5,
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We can see this if we look at just
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Okay, we do have authentication enabled,
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If we're still getting authentication failed,
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or actually, invalid authentication
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Probably means that our
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0:08:38
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So, if we look at the Show Key Chain,
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it shows in parentheses that the passwords is correct,
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0:08:54
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The reason is that when I was
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I was using the question mark
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to figure out, was there some other argument
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So, afterwards, I hit carriage return, but in reality,
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So, this actually is the correct
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0:09:24
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you can use what's kind of considered
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by putting additional white space
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0:09:33
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Because now, when someone looks at this
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0:09:39
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if someone looks at the running config,
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they know what the password is.
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0:09:43
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Okay, or at least they think
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But if we highlight this, we can see...
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that there's actually an
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So, if I said the key string is PASSWORD
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it means that is actually the P-A-S-S-W-O-R-D
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0:10:09
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So, you can use the null character, it is
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0:10:15
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And this is gonna be true both for the
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0:10:29
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So now, let's modify this. Let's go to the...
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The key chain, we'll say Key Chain RIP.
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0:10:37
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For Key 1, I don't want the old key string.
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Instead, I want the key string...
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And I need to go back to the chain.
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PASSWORD with no space after it.
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So, if now look at the Show Key Chain,
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0:11:02
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we can see it shows PASSWORD in quotation
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0:11:08
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And if I Show IP Route RIP,
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0:11:11
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and see any routes that are being installed
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then, I can assume that the
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0:11:23
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Which it is here.
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