In this example we've got two switches and four routers which are acting as PCs in the typology.
We also got a hub which I'm going to use to capture traffic using wireshark these devices have just
booted up.
So they have no configuration on the first switch or give the switch a hostname of ACE or one.
And on the second switch give it a host name of a to show villain at the moment.
We only have one Internet villaine configured movieland one all ports on the switch are configured in
that villain.
So because switches also have some older villains by default 1083 4 and 5 which we used previously for
FDDI and Token Ring those villains are not used any more today.
Switch to shows something similar.
So show villain brief villain one all ports are configured in villain one has wrote a one which is acting
as our PC.
I'm going to configure the first Ethan an interface with an IP address of 10 1 1 1 slushed 24 mosque
and no shut the interface
on rodder to do something similar.
No shut the interface.
Give it an IP address of 10 1 1 2
so without any further configuration we should be able to ping between Rotto 1 and router to notice
Rodda 2 can ping Rato 1 and router one can ping right to the switches just have a default config.
All ports on the switches are in villaine one we can see that by using the command show interface gigabit
to 00 switch port the port gigabit 00 is using administrative mode to dynamic auto operational mode
at the moment is static access negotiation of trunking is on.
In other words DTP is enabled but at the moment because there is no switch to negotiate with the porters
in Villon one the default Villon.
Now we can see the traffic by doing a capture using wireshark
various traffic is seen here weve got a spanning tree BPT view being sent by the switch.
We can see Cisco discovery protocol messages being sent by the switch as well showing the switch port
the platform and other information.
But what I'd like you to see is all traffic is Ethernet frames.
There is no data to the one Q tagging on these frames.
Let's do a search for ICMP traffic at the moment.
There is no ICMP traffic.
I'll get to Radu one to ping rockety And notice we see the ICMP traffic what you'll notice is we have
the source mac address of Rodda one pinging rodded to protocol type is IP version 4 source IP version
for addresses 10 one on one destination IP addresses 10 1 1 2.
It's a standard isa net frame encapsulating IP and ICMP.
In this case it's an echo and the reply is an echo reply.
There is no ethernet tagging on those frame at all.
It's a standard.
Each Samit frame there is no concept of Villani the novae line information is transmitted on the frame's
even the other frames such SCDP don't show any Vilain information whatsoever.
I'll stop that capture.
This is an access port and this is an access port by default.
The same will be true on switch to configure router 3 with an IP address of 10 1 1 2 3
no shut the interface and do something similar on route a full
no shut IP address 10 1 1 4
Ken Rotto for Ping rodders 3 acting as host 3.
Yes it can.
Start to capture here.
We can see various traffic tops being captured including once again CTP on rotas 3 or ping wrote a full
ping succeeds or full for ICMP And once again you can see that this is a stented Ethan frame.
There is no information about villans contained in these frames just stented Ethan frames.
So the PCs in the typology are unaware of any Vilain information they are sending untagged frames.
In other words stented Ethan It frames to the switches and the switches are sending untagged frames
to the PCs.
Now let's concentrate on switch one for the moment.
I'm going to set the VCP mode of the device to transparent which means it won't try and synchronize
Vilain information with the other switch.
Shrivelling once again shows us that we have one Ethan that villaine configure it.
Let's create relend to show the land brief.
We now have to eat at a villans but no ports are configured in the land to.