V5 provided a standard set of protocols from the subscriber to the LE. The AN (or Access Network) was defined as a reference point. Signalling between this point and the LE was standardised and therefore allowed a multiple vendor solution, provided the specifications were followed. This resulted in a single link (or in the case of V5.2 multiple links) from the AN to the LE, reducing the need for many lines along this point (or more likely no need for a proprietary solution to manage the single link). The final link to the local loop remained the same with digital signalling (ISDN) and analogue signalling for basic telephony (also known as POTS in the industry).