OT: Authentication in STP

Hi fellas,

My customer is asking for any authentication in STP. Can someone tell me
that if there is any Authentication mechanism in STP to validate to correct
birdges with some hash value and try to avoid rogue bridges with this. I
searched in RFC's and i guess there is no Authentication mechanism in STP .
So is there any other IEEE standard for STP Authentication.
I found Cisco Proprietary Root Guards which basically tells avoid any
superior BPDUs and avoid that port as Root port.

I know Root Guard doesnt do any authentication . But is there any other
mechnaism where can do authenticating the bridges in STP logic

I believe Radia Perlman is still kicking for this :)

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CCIE KID
CCIE#29992 (Security)
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