Network Computing Devices Inc of Mountain View, California, has developed a new transport protocol to enable efficient communications over serial lines from its X Window network display stations to local or remote sites. According to the company, the new XRemote protocol has been designed specifically to do multi-level data compression in X Window System environments, enabling X terminals to be used not only in Ethernet installations, but over telephone line and RS-232 connections. Network Computing’s executive vice-president Judy Estrin said that XRemote was designed for local communications where high speed local area network services were not available, or for remote communication from branch offices to the central computer. It provides around 10 times the performance of the Serial Line Internet Protocol, currently the most popular means of serial connection of X terminal products, and is necessary, says Network Computing, because of the heavy bandwidth demands of bit-mapped workstations and windowing systems. Built-in reliability mechanisms are designed to cope with noisy lines and modem errors. The software is run from the display terminal itself rather than the host computer. The XRemote PROM set, containing XRemote (rather than TCP/IP) and all other standard Network Computing Devices software costs $300 per unit: any unit can be connected to a TCP/IP Ethernet network by re-booting from the network rather than the PROM. Network Computing is expected to reveal colour versions of its display terminals at the forthcoming UniForum show in Washington at the end of the month.
