BT Infinity FTTC - Inhouse Wiring

Have been unable to find a diagram of the basics for the in-office end of a BT-Infinity-FTTC service.
Normal Broadband easy to understand, with any Socket (Master or Extensions) able to attach Broadband-Router and other PSTN (such as Voice-Handset and Fax-Machine) each via their own Micro-Filter.
BT-Infinity-FTTC seems to be Router only attach via a Master-Socket. Ignoring the PSTN socket on the front of the Master-Socket (which is in an inaccessible location for Router & Ethernet Hub), what is used at each Extension-Socket to continue to allow PSTN devices such as Voice-Handset and the Fax-Machine ?

FTTC is just like ADSL was back in its early days on 2000 to 2003.

Master socket with faceplate filter system, or on the end of a dedicated data extension called Home Wiring Solution, which is ordered when ordering service (and is free) and can give a data socket up to 30m from the master socket.

http://www.coolwebhome.co.uk/faceplate/ shows the FTTC faceplate and how it fits a normal master socket.

With FTTC the desire to minimise extra cable is such that if at all possible run the openreach modem at the master socket, and then running up to 100m of Ethernet cable between the openreach modem and the HomeHub.

what is used at each Extension-Socket to continue to allow PSTN devices such as Voice-Handset and the Fax-Machine

nothing, it's centrally filtered.

Thanks for the feedback.
Ordered BT-Infinity 6 months ago... So far 8 different Engineers (BT Assist, Openreach & Kelly) have all failed to get the Sockets wired to allow Infinity-FTTF Router connection.
Still can't get any to understand that a new FacePlate doesn't designated the Master ( I now, so far, have 2 FTTC FacePlate Extensions - neither of which is the Master), Thanks to you I now also know they need to ensure our Extension-Sockets fall from the Master PSTN Filtered connection.