Association Category and Metadata Group

siva2_2000

Friends,
I need some information about MediaBin’s Association Category and Metadata Group.
1. How can I get the asset’s Association Category’s asset using MediaBin Web Srevice?
Example:
Piano front view image is linked with an Association Category Name (EL-100) which has 2 side view images.
2. I have some Metadata Groups with some metadata names. How can I get Metadata Names by Metadata Group Name?. I could not see any webservice method like MetadataByGroupName().
How to do these ??

Thanks in advance
shiv