class 5 switch
In the USA, the large telephone switches are classified in the switching technology of public networks.
The Class 5 switch is a switch of the lowest hierarchy for local switching. In the case of the public switched telephone network( POTS) and ISDN, the Class 5 switch operates as an access switch for the end user; in the case of an Internet service provider( ISP) connection, it operates as an output switch on the trunk side.
In the public telephone network, the Class 5 switch forms the termination for voice traffic and typically has a capacity of up to 100,000 access lines to the subscriber terminals( CPE).