Access-Trunk link issue

yamenginena · ‎03-11-2012

Dear All,

what happen if two switches connected using utp cable one end configured static access and the other end configured statis trunk ?

and if it will not work why ?

Thanks

Jan Hrnko · ‎03-11-2012

Hi,

I think that it will work but:

The side that has static access configured will accept only non-tagged frames, because it does not anticipate tagged ones (host side(port) is not even suposed to know in which vlan is he assigned to and host side is not allowed to generate tagged frames). The side that has trunk configured will generate both tagged and untagged frames. As you may know - untagged frames are from hosts that are in the native vlan. So the conclusion is that in such a scenario only hosts in the native vlan would be able to communicate through this link (trunk-access).

Best regards,

Jan

jimmysands73_2 · ‎03-11-2012

Just a refresher....

DTP Combinations

Figure 1 Administrative Mode Combinations and their Operational Modes Administrative Mode	Auto	Desirable	Trunk (on)	Access (off)	Non-Negotiate (access)	Non-Negotiate (trunk)
Auto	Static access (NT)	Trunk	Trunk	Static access	Static access	Unexpected Results
Desirable	Trunk	Trunk	Trunk	Static access	Static access	Unexpected Results
Trunk (on)	Trunk	Trunk	Trunk	Unexpected Results	Unexpected Results	Trunk
Access (off)	Static access	Static access	Unexpected Results	Static access	Static access	Unexpected Results
Non-Negotiate (access)	Static access	Static access	Unexpected Results	Static access	Static access	Unexpected Results
Non-Negotiate (trunk)	Unexpected Results	Unexpected Results	Trunk	Unexpected Results	Unexpected Results	Trunk