KA9Q, also called KA9Q NOS or simply NOS, was a popular early implementation of TCP/IP and associated protocols for amateur packet radio systems and smaller personal computers connected via serial lines. It was named after the amateur radio callsign of Phil Karn, [1] who first wrote the software for a CP/M system and then ported it to DOS on the IBM PC. As the KA9Q package included source code, many radio amateurs modified it, so many different versions were available at the same time.
KA9Q was later maintained by Anthony Frost (callsign G8UDV) and Adam Goodfellow. It was ported to the Acorn Archimedes by Jonathan Naylor (G4KLX). Until 1995 it was the standard access software provided by British dial-up internet service provider Demon Internet.
Most modern operating systems provide a built-in implementation of TCP/IP protocol; Linux especially includes all the necessary kernel functions and support utilities for TCP/IP over amateur radio systems, as well as basic AX.25 and NET/ROM functionality. Therefore, NOS is regarded as obsolete by its original developer. It still may have its uses for embedded systems that are too small for Linux. [2]
KA9Q is also a name for the IP-over-IP Tunneling protocol.
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AX.25 is a data link layer protocol originally derived from layer 2 of the X.25 protocol suite and designed for use by amateur radio operators. It is used extensively on amateur packet radio networks.
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EchoLink is a computer-based Amateur Radio system distributed free of charge that allows radio amateurs to communicate with other amateur radio operators using Voice over IP (VoIP) technology on the Internet for at least part of the path between them. It was designed by Jonathan Taylor, a radio amateur with call sign K1RFD.
Phil Karn is a retired American engineer from Lutherville, Maryland.
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Douglas Earl Comer is a professor of computer science at Purdue University, where he teaches courses on operating systems and computer networks. He has written numerous research papers and textbooks, and currently heads several networking research projects. He has been involved in TCP/IP and internetworking since the late 1970s, and is an internationally recognized authority. He designed and implemented X25NET and Cypress networks, and the Xinu operating system. He is director of the Internetworking Research Group at Purdue, editor of Software - Practice and Experience, and a former member of the Internet Architecture Board. Comer completed the original version of Xinu in 1979. Since then, Xinu has been expanded and ported to a wide variety of platforms, including: IBM PC, Macintosh, Digital Equipment Corporation VAX and DECstation 3100, Sun Microsystems Sun-2, Sun-3 and SPARCstations, and Intel Pentium. It has been used as the basis for many research projects. Furthermore, Xinu has been used as an embedded system in products by companies such as Motorola, Mitsubishi, Hewlett-Packard, and Lexmark.
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KISS is a protocol for communicating with a serial terminal node controller (TNC) device used for amateur radio. This allows the TNC to combine more features into a single device and standardizes communications. KISS was developed by Mike Cheponis and Phil Karn to allow transmission of AX.25 packet radio frames containing IP packets over an asynchronous serial link, for use with the KA9Q NOS program.
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