Pleasanton, California-based Livingston Enterprises Inc has introduced a family of ISDN products said to be the first to use AT&T Corp’s new T7903 ISA-MWAC Multiport Wide-Area Connection ISDN chip, which incorporates complete ISDN functionality on a single integrated circuit. The PortMaster ISDN Communications Server is a central-site unit with 10 115.2Kbps asynchronous ports, one or two five-port ISDN Basic Rate Interface modules and an optional synchronous T1/E1 router port, says the firm, which adds that units equipped with two BRI modules can support up to 20 64Kbps ISDN B channels. The unit includes fully integrated NT1 network termination (U interface), and can serve as routing hub linking remote local networks, or a dial-in user hub. The device also supports the Multilink Point-to-Point Protocol Protocol, as well as V.120 rate adaptation. The PortMaster ISDN Office Router offers one ISDN Basic Rate Interface port, and features Multilink Point-to-Point Protocol support. The offering also has an Ethernet port, as well as a 115.2Kbps asynchronous port, which provides dial back-up for the ISDN ports or accommodates dial-in users without needing a separate communications server, says the firm. The PowerLink128 ISDN Modem for AT-based personal computers is said to provide up to 128Kbps transmission. Offering one Basic Rate port with integrated NT1, the board appears to the personal computer as a virtual communications port, enabling client software to run unmodified, says Livingston. The device supports V.120 rate adaptation, with the ability to multi-link two V.120 channels for a single 128Kbps connection; a later software release will support synchronous Point-to-Point Protocol. The PortMaster ISDN Communications Server, available now, is priced from $4,690 to $6,685. Versions that include an integrated T1/E1 routing over leased lines or Frame Relay go from $5,490 to $7,485. Five-port ISDN Basic Rate upgrade modules for existing PortMaster units are $2,000 each. The PortMaster ISDN Office Router, available in early December, is priced at $1,200. The PowerLink128 ISDN Modem, available in mid-December, is $300.
