looking at 802.1Q frames

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Hello!

Just for fun I decided to look at 802.1Q frames between two trunk ports
that connect two 3524. What I did is connect the trunk ports via a hub
and use Ethereal to watch the traffic.

What I was expecting to see were 0x8100 tagged frames, but just saw
standard Etherent tags.  Setting the trunk  encapsulation to ISL works
as expected. This is the configuration for the trunk interface

interface FastEthernet0/24
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1,98,99,1002-1005
 switchport mode trunk

My undertanding of non tagged frames was that only the Native VLAN
frames are untagged on the trunk.

What am I missing?

TNX

/CM


Re: looking at 802.1Q frames

Capitan Mutanda wrote:
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i'm so sorry i do not know


Re: looking at 802.1Q frames
Were there any active vlans being carried in the trunk?
If vlans 98-99 don't exist, they won't be carried will they?


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Re: looking at 802.1Q frames

jw wrote:
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Yep. On vlan 99 I put an ftp session of a whole cd image while on vlan
98 there was a continous ping.

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