British telephone socket - Wikipedia A domestic single British telephone line installation will have a single master socket or line box in the premises, which is provided by BT or another service provider: this socket is the demarcation point between the customer-owned and maintained on-premises wiring, and the telephone network installations using the NTE5 line box (NTE for network termination equipment), the demarcation Structured cabling - Wikipedia Structured cabling network diagram. Structured cabling design and installation is governed by a set of standards that specify wiring data centers, No adapter is needed in North America as the 6P2C and 6P4C plugs most commonly used with RJ11 and RJ14 telephone connections are physically and electrically compatible with the larger 8P8C What is Surge Protection? A Guide to Surge Protection Devices Telephone Surge Protection Devices – these act as adaptors for the RJ11 or RJ12 port connected into, This is a surge protection circuit diagram showing a circuit built with a gas discharge tube. It is designed to protect electrical equipment by implementing redirection in the case of an overvoltage event. Surge Protection Device