Brocade Access Gateway or ISL trunks ?



We have two McData 4500 switches connected to CX500. We're adding an
HP c-class blade enclosure with two Brocade switches. Should I use
the Brocade Access Gateway or ISL trunks to connect them? Either way
I have to buy some options/licenses; with access gateway included on
the brocades I need to license NPIV option on the 4500's. With ISL
trunking I need the ISL trunking license for the Brocades and
(probably) the open trunking license on the McData's.

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