a little about RIP

1°) is there any way that authentication  can be enabled on a per neighbor basis for RIP on a multi access interface  ? 

2°) what  would be a valid design case where even with version 2 of RIP enabled, we will need to enable its v2 broadcast capability for update to be exchaged properly (except the case multicast for 224.0.0.9 would have been filtered) ?

Thanks for your input.