A line card is an electronic circuit that is positioned on a separate circuit board. It acts as an interface between the subscribers of a telecommunications network and the rest of the network.
Line cards are connected to the public telephone network (PSTN) with a twisted two-wire cable of a POTS subscriber line. Tasks include call monitoring, line integrity tests, conversion of voice transmissions from analog to digital or the other way around and lifting the handset.
Line cards are an important component in large networks as they enable connectivity and data exchange between different networks and servers. They can support different speeds, protocols and interface types depending on network requirements. Thanks to their flexibility and expansion, they enable the configuration and scalability of network devices.