Manually pruning interface still seeing other Vlans bcast/mcast
I'm looking at an issue with where i'm spanning a port and capturing using wireshark. I just wanted to understand why i still see bcast and mcast going down an interface towards a Cisco IP phone which is also connecting a laptop also. I don't know if i'm going crazy here or if i am confused about the concept of vlans, broadcast domains etc...
By my logic i shouldn't see any broadcast traffic from another unicast address which is outside of my telephone IP and my Data network IP, why am i seeing traffic on the trunk to the phone even with manually selecting vlan pruning to only these two specific vlans.