[NOTE: Please click the ‘DOWNLOAD’ button to your right to download the config files for this lab exercise]
Transcript: Welcome to this CCDA lab. Today, we’ll be discussing some curious features, traffic-shaping and traffic-policing.
So in this lab we have two routers. We have R1 and an ISP router so we’re assimilating something like an organization’s router connected to the ISP. Right and this is the LAN.
So let’s take a look at the configuration in R1. Sure run. Right now we have a class map. So we have a class map called QSC map, and it matches an access group called QSACL. If you look at that, QSACL, all it does is to permit ICMP. Any any. Right? And then the class map is used in two different policing maps. One for shaping and one for policing. Right? And that’s about it.
CCNA Quad Instant Pricing – Intense
So if I come here now. Actually, lets check the IP address of this ISP router. So show IP interface pref. It’s 192.0.0.1. Okay. So let’s come to this guy. And let’s ping. Or let’s use some options. So I want to increase the count. And I also want to increase the size. So I’m going to ping 1900.0.1, and I’m going to use size of 1300 bytes. It defaults that this one uses is 84 bytes. On Cisco router the default is 100 bytes. And then we’ll use a count of ten. Right. So let’s see what happens.
So I want you to keep your eye on this time. You will notice that the average right now is about maybe 47 milliseconds, right? So say 47 milliseconds.
So let’s come back to R1. And we’ll go on that the interface. Let’s start with policing. So I’m not really sure whether it’s policing or policing, so I’m just going to stick with policing. So we’ll want to apply our policy, that’s this one. So the policy map. This one that has to do with policing. We’ll want to apply it to the interface, so that it limits the ICMP traffic to this particular figure, alright?
Now we can, for policing, you can apply it either in-bound or out-bound. So I can apply it in-bound this interface or out-bound this interface. Let me just apply it out-bound. So it’ll be something like service policy. And then let’s take the name. That’s this one. Actually I need to configure whether it’s in-bound or out-bound. So I’m going to say out-bound. And then now if I check ‘show policy map interface’. We’ll see that. So we can see the CRR is 8000 BPS. This is 1500 bytes. Right now, there’s no packets that we’ve sent, so everything right now is 000.
So let’s come back to this guy and ping again. So the first one went through. The second one failed. The third one went through. The fourth one failed. And that’s how we’re going to see. So if we check here, we’re going to see, let’s just wait for it to finish. So let’s check it again. Okay. So we see ten packets, right? And the ones that conformed, five packets conformed. And they were transmitted. And the ones that did not conform. So that’s the one that exceeded the weight dropped. So that’s why you notice that we have all of this time out here. So that’s what policing does. Any traffic that does not conform to the amount of the figure that you have set will be dropped. Right?
So now let’s change it to shaping. I’ll remove this and put the one for shape. Delete. Delete. And let’s see the difference now. Alright so let’s ping again. So all that is going through. There’s no problem, but just keep your eye on the time. Right. Keep your eye on the time. Alright.
So remember what we said for shaping. The traffic that does not conform, it is not dropped, it is just slowed down. So if you notice here, this one had a very great slow down. And this one, and also this one. So if we’re to check it again, to show policy map interface. The output is a bit different from policing, but we can see the packets that we delete here. Two packets we delete. And the bytes that we delete are this.
So let’s try a higher. Let’s say 1500 and let’s see what happens. Less than another one. So first of all, you notice that this one, a lot of packets were delayed, right? So let’s check. So we had nine packets delayed. Well along with other one that we’re running. But then that’s how you see the difference between policing and shaping. So with policing, if the packet does not conform, it is dropped. But with shaping, if the packet doesn’t conform, then it is just slowed down, like put in a buffer or something like that.