The Cisco AS5400RM-19 is a high-density, carrier-class access server designed for service providers and large enterprises. It is part of the Cisco AS5400 Series, which offers scalable and flexible solutions for remote access, voice over IP (VoIP), and fax services. The AS5400RM-19 is a rack-mountable version of the AS5400 access server, designed to be installed in a standard 19-inch equipment rack. It provides a high port density, with support for up to 336 digital voice channels or 252 analog voice channels, making it suitable for large-scale deployments. The AS5400RM-19 offers a range of features and capabilities, including support for various network protocols, such as IP, IPX, and AppleTalk. It also supports a wide range of voice and fax protocols, including H.323, Session Initiation Protocol (SIP), and T.38 fax relay. With its high-density design and advanced features, the Cisco AS5400RM-19 is well-suited for service providers and enterprises that require a reliable and scalable solution for remote access, VoIP, and fax services.