[c-nsp] Es20+ card and licensing question

[Webster, Andy]

Hi,
	I'm looking at the ES20+ cards for 7600s and I am confused by
the licensing options.  There are two license options 76-ES+BASIC and
76-ES+ADVIP.  Do I need to purchase one of these two options for each
ES20+ card or is it possible to run the card without either license?  Is
each license linked to a specific card?  Do I just purchase enough
licenses to cover the cards I have in use and forget about it?  Are the
licenses each linked to a specific card's serial number?  What happens
if I rma the ES20+ card?  Would I have to get the old card's license
associated with the new rma'd card?  
	I see that Layer 3 IP/MPLS VPN requires the 76-ES+ADVIP license.
I figure that means as soon as I put 'vrf forwarding test' on an ES20+
interface and pass some traffic over it the 76-ES+ADVIP license is
required.  Am I correct about that?

Thanks in advance,
Andy Webster