perf event: what does mean node-* event [HW cache event] ?

Hi all

I've been looking into perf events.
I understood L1-*,LLC-*, iTLB-*, dTLB-*, etc in HW cache events. But I don't know what node-* event mean very well.
In HW cache field, what does 'node' word mean ?
And Can you help me understand node-* event ?

(I found a similar mail in this mailing list,
but I didn't look for the answer for the mail.)

Thanks,
Taeung