I had FTTC at another location which was installed by BT/OR. The 'master' socket had landline and broadband ports and I didn't use a filter.
I'm getting a connection at a new location where I'm plugging in myself. The 'master' socket here is a type "5C" which has only one phone port.
Where do I plug my modem/router in?! Do I need a filter? Like the ones I used to use back in the ADSL days? Like one of the half dozen I threw away?