CQD to differentiate P2P and Conference Meeting

That's pretty simple. 

You have to upload your "Building Data" ( I assumed you have already uploaded?) with different subnet info, for example:

1. Office-1 associated with 10.0.0.0/8

2. Office-2 associated with 172.16.0.0/12

3. Office-3 associated with 192.168.1.0/24 

At "Filter"

Select "Second Network" and select all your 3 network ranges (or more);

10.0.0.0/8

172.16.0.0/12

192.168.1.0/24 

At "Dimension"

Select "Second Network" 

If you see the networking ranges are overlapping each other on the resulted graph, just leave it as it as, and instead download it as Excel Sheet - it will show you statistics very clearly.