ARRL 1st-4th Computer Networking Conference 1981-1985

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1st Computer Networking Conference
October 16-17, 1981

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Location:: National Bureau of Standards, Gaithersburg, Maryland
Coordinator:: Paul L. Rinaldo, W4RI
Hosted by:: Radio Amateur Satellite Corporation (AMSAT)
Amateur Radio Research and Development Corporation (AMRAD)

Abstracts:

Amateur Packet Network Agenda
by Paul L. Rinaldo, W4RI: Introduction - The American Radio Relay League (ARRL) is sponsoring this first international Amateur Radio Computer Networking Conference for several reasons. One is to recognize the innovative work that Canadian and U.S. amateurs have already done in packet radio. Another is to explore the possibilities of an integrated amateur packet network. Assuming that there is a consensus that a network can be developed, the third is to try to set up a framework for orderly growth.
This paper outlines my current thinking on some aspects of amateur packet radio networking. I have included a number of things that I believe should be considered at this conference and in the few months ahead.
SOFTNET - Packet Radio in Sweden
by Jens Zander, SM5HEV: Abstract - An experimental packet radio network is under construction at the University of Linkoping, Sweden. The network is distributed and all nodes are programmable via the network during normal operation. This concept gives full flexibility at all levels. Experiments at low levels, such as access schemes, as well as at high levels, such as routing and flow-control, are possible. Finally, the implementation of the network is sketched.
An Expandable Microwave Network for Multimode Communications
by Dave Ingram, K4TWJ: The projected network described in the paper was originally conceived with the purpose of interlinking communities and cities on a broadband basis. Numerous other capabilities, however, were soon included to permit almost direct compatibility with future communication expansions. The resultant network is highly flexible: it may be instigated between adjoining communities and or cities, with additional networks being implemented in other areas and interlinked as desired. Communication modes which ca n be handled by the network are limited only by users desires and their respective modes. A basic outline of the microwave network shown in Figure 1, and an overview of its operation follow.
Deaf Telecommunications Networking
by Barry Strassler: Thank you every one of you for giving me the opportunity to give you a glimpse into the world of deaf telecommunications. It should be of interest to you because out technology interrelates with yours in many ways, and perhaps might even spur you on to better developments.
From RTTY to Packets
by Joe Kasser, G3ZCZ: Introduction - Putting a microprocessor into an RTTY station can improve the usefulness of the station by orders magnitude. RTTY comes in various aspects: there is the old fashioned Baudot network chugging along at 45.5 baud; the new ASCII links are running at 300 bauds and exchanging computer data; and, up and coming are the packet radio networks. This article discusses the whole arena of digital communications and shows how each is a step in the whole picture; and how as computers are added, a digital network can be developed that can accommodate users with almost and equipment (e.g., a Model 15 Baudot machine and an ASCII terminal) can communicate via microprocessor based repeaters.
Network Architecture and Protocols for a Widespread Amateur Digital Communications Network
by Douglas Lockhart, VE7APU: In the last couple of years the Vancouver Amateur Digital Communications Group (VADCG) programmable communication controller has been used in many areas of the U.S. and Canada. As one of those who worked on the development of the board and its software, I am very please to see that it has gained fairly widespread acceptance in the Amateur Radio fraternity. It was not so clear, a couple of years ago, whether or not it would be accepted because it involved the use of techniques unused in Amateur Radio at the time.
On the Care and Feeding of Your Packet Repeater
by Hank Magnuski, KA6M: Abstract - This paper will describe the construction and functioning of the KA6M packet repeater, and will report on the operational results during the first 10 months of service. Since its initial turn-on in December of 1980, the repeater has been transformed from an experiment to a major Bay Area repeater serving a user group now approaching 30 stations. The repeater has been extremely important in testing new hardware and software, and in provoking interest in the area's amateur community.
On the Use of a Two-Frequency Traditional Voice Repeater for Local Area Packet Networking
by David W. Borden, K8MMO: Abstract - In using the VADCG Terminal Node Controller (TNC) board in the Washington D.C. Metro area, members of the Amateur Radio research and Development Corporation (AMRAD) have found it convenient to use an existing voice two meter repeater for packet work. This paper addresses some of the problems encountered with this approach and some of the benefits that accrue.
Formation of Local Standards in North Jersey Packet Group
by E. Robinson, W2FPY: The successful introduction of digital packet communications to amateur radio depends not only upon the technical standards of the hardware and software of the packet interface, but also upon the resources and needs of the local amateur community. The planning of a local packet network requires examination of factors such as the available engineering talent, financial resources of both individuals and the packet group as a whole, and pre-existing user equipment.
An Emergency and Routine Communication Network for Illinois Using Packet Radio Techniques
by Richard W. Doering, WA6CFM and Forrest R. George, W9SKD: Abstract - Amateur Radio teletypewriter and computer communication may be enhanced using a packet radio network to time share network nodes, detect and correct errors, expand geographic coverage, and facilitate bulletin broadcasting. The network is based on a access 0 persistent protocol. Application of such an area packet radio network to emergency and routine communication in northern Illinois is discussed.
Computer-Controlled Message Handling
by Russell D. Ward, Jr. WA4ZZU: Although usage of computers in Amateur Radio is slowly increasing, some study should be given to methods of promoting this utilization. This paper will show two methods of increasing computer message handling in Amateur Radio. These two methods are increased availability in the middle-term future and increased use of present capacity.
Notes on Closing Session
by David Engle, N6FTZ
A General Letter to Packet Radio Enthusiasts
by Hank Magnuski, KA6M
List of Attendees
compiled by Bill Pala, WB4NFB

2nd Computer Networking Conference
March 19, 1983

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Location:: San Francisco, California
Coordinators:: Hank S. Magnuski, KA6M
Paul L. Rinaldo, W4RI
Hosted by:: Amateur Radio Research and Development Corporation (AMRAD)
Pacific Packet Radio Society

Abstracts:
2nd Computer Networking Conference
March 19, 1983

The PACKSAT Project
by Den Connors, KD2S: Abstract: AMSAT has begun the design and development of a new form of Amateur Satellite. The PACSAT series of satellite systems has as a design goal total I global access by all hams to a store-and-forward packet radio message handler. AMSAT is proposing the design and prototyping of a satellite-based experiment for advanced digital packet satellite communications experiments.
AX.25 Level 2 Protocol
by Terry L. Fox, WB4JFI: Abstract: This paper contains the latest draft of the AX.25 protocol specification. This is the first public release of this draft. Earlier drafts have been given to specific individuals for comment and as a reference for software development. Changes should be expected. Please check the AMRAD Newsletter for announcements of later versions.
Level 3 Position Paper
by Terry L. Fox, WB4JFI: Abstract: Now that the amateur packet radio community seems to have agreed on a protocol at layer 2, the link level of the Open System Interface Reference Model (OSI-RM), it appears that it is time to begin to work on the layer 3, or network layer. Layer 3 is actually made up of two sub-layers, a local and metropolitan network sub-layer, and an internetwork sublayer.
A New Packet-Radio-Controller Board
by Terry L. Fox, WB4JFI: Abstract: This paper dessribes the AMRAD packet assembler/disassembler (PAD) to be released soon. It is Zilog Z80A based, uses a Zilog 8530 serial communications controller and is packaged on an S100 pc board.
Design Decisions for the TAPR TNC Link Level
by David Henderson, KD4NL: Abstract: The decisions that were made up front on the software side of the TAPR project have had a very strong impact on the implementation and success of that project. Following is a review of some the design decisions that were made long before coding started, and a chronicle their impact upon implementation and performance.
Unique Features of the TAPR TNC
by Lyle Johnson, WA7GXD: Background: The Tucson Amateur Packet Radio (TAPR) Terminal Node Controller (TNC) began as a local project done by a handful of Tucson-area Amateurs late in 1981. The project attracted enough attention to cause the formation of a formal club as well as an enlarged number of participants. As interest continued to grow, TAPR incorporated as a nonprofit R&D group, and the TNC project changed from a local effort to include active participation in the design, implementation and testing phases with Amateurs from the West Coast to the Northeast.
Modulation and Access Techniques for PACSAT
by Phil R. Karn, KA9Q/2: Abstract: This paper describes work underway within AMSAT to define modulation, channel access methods, and related system-level considerations in the I design of the store-and-forward packet I radio satellite known as PACSAT. This is not intended as a comprehensive design specification, primarily because I one doesn't yet exist! In particular, I only those decisions primarily concerning spacecraft hardware design are emphasized here, since the details I of control algorithms, protocols, etc, will reside in software capable of being changed and reloaded into the onboard computer(s) after launch.
A Block-Oriented Interface for CP/M and the VADCG Terminal Node Controller
by Douglas Lockhart, VE7APU/3: Abstract: This paper describes a system of hardware and software which provides for the transfer of blocks of data between a VADCG Terminal Node Controller (TNC) and a CP/M system with a serial interface. Both the software to run in the TNC and in the CP/M system is included. The system provides block transfers, data transparency, flow control and error checking and retransmission in both directlons over the interface.
Link-Level Address Mechanisms in Amateur Radio Protocols
by Hank S. Magnuski, KA6M: Abstract: In October, 1982, agreement was reached on a new Link Level protocol for amateur packet radio networks. One of the unique aspects of the protocol is the set of address f ields used at the beginning of each frame. This paper reviews the types of addressing used prior to the adoption of the new standard, and explains in detail how the new address mechanism works.
Real-Time Low-Level Software on the TAPR TNC
by Margaret Morrison, KV7D: Introduction: This paper describes the low-level assembly language routines (LLR) of software released with the Tucson Amateur Packet Radio (TAPR) Beta Test terminal node controllers (TNCs). The primary functions performed by these routines are initialization of peripheral devices and data in RAM, maintaining input and output (I/O) buffers, servicing interrupts from peripheral devices, handling nonvolatile RAM data storage and retrieval, and calibration and checkout routines. Entry points are provided which are appropriate to the subroutine calling sequence of the Pascal compiler used for the high-level routines (HLR). In addition, a low-level debug program provides capability for direct access to peripherals, inspection of RAlf and ROM locations, and execution of temporary code in RAM. The present LLR code occupies about six kilobytes of ROM.
Designing the TAPR TNC Audio Input Filter
by Margaret Morrison, KV7D and Dan Morrison, KV7B: Abstract: Standard modulation for present terminal node controllers is Bell 202 compatible 1200 Hz / 2200 Hz phase-continuous FSK. Fig. 1 shows the typical spectral characteristics of such data. Notice that frequencies ranging from about 500 Hz to 2900 Hz are present in random NRZI data. One might guess that frequencies outside the central region from 1000 Hz to 2400 Hz could be eliminated with no degradation of demodulator performance. This turns out to be incorrect: the demodulator PLL needs this information to ensure timely response to data transitions. Thus, the ideal audio response over the link should be flat from below 500 Hz to over 2900 Hz.
Packet Radio for Emergency Communications
by Bob Neben, K9BL: Abstract: There is a need to redesign the techniques we use to handle emergency trafflc. Many of us are combining processor controlled equipment and traffic handling techniques designed in the 1930's.
Multi-use Design Considerations for the TAPR TNC
by Harold E. Price, NK6R: Abstract: The Amateur Packet Radio Terminal Node Controller (TNC) built by TAPR Inc. is designed to meet the needs of a wide range of users, from the technical experimenter to the "appliance operator" end user. This paper discusses the human engineering factors which went into the design of the TNC's external software interfaces that enable it to serve a heterogeneous user
Packet Radio - A Software Approach
by Robert M. Richardson, W4UCH: Abstract: A software rather than hardware approach to synchronous Packet Radio communication at 1200 or 2400 Baud using the Radio Snack TRS-80, Model I or Model III microcomputer is described. The program duplicates virtually all the functions provided by the Vancouver Area Digital Communications Group (VADCG) terminal node controller board which requires an 8085 microprocessor, an 8273 synchronous data link controller (SDLC), an 8250 serial I/O, and a number of EPROM and RAM memory chips, plus a separate microcomputer with RS232C interface and a 1200/2200 Hz modem.; The only external equipment required by the software approach, other than a TRS-80, amateur VHF transceiver and antenna, is a port zero encoder/decoder, and two EXAR chips for AFSK keying and demodulation. The proqram has been extensively tested on the 2 meter amateur band working into southern Ontario and locally in western New York.
Introducing the Packet Adaptive Modem (PAM)
by Paul L. Rinaldo, W4RI: Abstract: This paper describes a modem design undertaken by Robert E. Watson and the author. The modem was designed primarily for high-freguency packet radio applicatlons. It operates at slgnaling rates of 75, 150, 300, 600 and 1200 bauds. The data rate is sof tware controllable through a modifled RS-232-C port. A frequency shift of 600 Hz is mamntained for all data rates. The modulator is phase continuous and provides X32 or X64 clock to the packet assembler/disassembler (PAD) or termlnal-node controller (TNC). The demodulator employs a National MF10 switched-capacitor filter SCF chip for each of the 1500-Hz mark and 2100Hz space frequencies. Bandwidths of the MF10s are software controllable to accoramodate different received data rates and receiver frequency tolerances. A Point-to-point wired prototype of the modem hag been built on an S-100 perf board. Power may be taken from the S-100 bus or provided by a separate power supply. The prototype has been laboratory tested with excellent "eye diagrams" on speeds up to 600 baud with some eye closing at 1200 bauds. Still pending is a design declsion whether to combine an optimal minimumshlft keying (msk) demodulator circuitry for 1200baud operation with this modem or to make it a separate modem. Upon completion pc boards and documentatlon will the made available to amateurs.
SOFTNET - An Approach to High-Level Packet Communication
by Jens Zsnder, SM5HEV and Robert Forchheimer: Abstract: SOFTNET is a packet-radio concept under development in Sweden. The network is distributed and all nodes are programmable via the network during normal operation. This concept represents an unconventional approach to the protocol issue and offers elegant solutions to the higher level communication problems. This paper gives a programming model of the network, along with some illustrating examples.

3rd Computer Networking Conference
April 15, 1984

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Sorry, ARRL 1st-4th Computer Networking Conference 1981-1985 is no longer available

This proceeding is available on CD-ROM

Location:: Trenton, New Jersey
Coordinator:: Paul L. Rinaldo, W4RI
Hosted by:: American Radio Relay League (ARRL)

Abstracts:
3rd Computer Networking Conference
April 15, 1984

Networking Considerations for the Amateur Packet Network
by J. Gordon Beattie Jr., N2DSY: Abstract: Several issues related to internetwork communications require the discussion and consensus of the amateur community if packet communications facilities are to be flexible for the users and coordinators alike. IN this article, the reader will be shown a system of suggested network hierarhies and the interface control procedures required. These hierarchies are patterned after the ARL's National Traffic System. This is not to say that this writer is suggesting a monolithic structure. In fact, some sections or regions may evolve with several networks covering the same area. This will occur as a result of demand or interest in a particular area. Such a situation is like having early ane late sessions of an NTS net, except packet networks can run continuously and simultaneously.
The Eastnet Network Controller
by David W. Borden, K8MMO: Abstract: This paper describe a proposed packet radio network control computer running at high packet baud rates on the East Coast Amateur Packet Network, EASTNET. Principally discussed is the digital hardware, but also mentioned is some crude digital side uses STD bus hardware developed by Jon Bloom, KE3Z to begin testing, and eventually will use the AMRAD Packet Assembler Disassembler (PAD) board running in an S-100 Bus (IEEE-696) computer.
HF Packets: Modems and Gateways
by Robert E. Bruninga, WB4APR: Abstract: With the increaseing Packet Radio activity and need for long-haul linking between Local Area Networks (LANs), a number of experiments are being conducted on the viability of packet radio on the HF bands.
Eastnet: An East Coast Packet Radio Network
by Robert E. Bruninga, WB4APR: Abstract: The idea of a digital packet radio network linking the East Coast was envisioned in the late 1970' 6 when the Department of Communications in Canada and later the Federal Communications Commission in the US authorized the transmission of digital data over amateur radio frequencies. Today, EASTNET is a reality with relay sites becoming operational in Washington DC, Maryland, New Jersey, New York, Connecticut, and Boston. By 1985, connectivity from Boston to Norfolk will be established. This paper will discuss the present status of EASTNET and will propose an orderly plan for development of a more sophisticated, higher data rate system. Repeater siting considerations and frequency planning will be addressed.
The Racing Problem: A Packet Solution
by Robert E. Bruninga, WB4APR: Abstract: Last June several members of AMRAD participated in the Old Dominion horse ride and 100 mile endurance run near Front Royal Virginia by providing mobile and emergency communications. A dozen or so checkpoints were manned by radio amateurs as well as shotgun riders with each of the key event and emergency personnel to provide VHF communication throughout the several county area of rural roads and 1500 foot mountains. A portable repeater was constructed out of two Icom 2AT walkie-talkies and battery powered throughout the weekend event. This was only the beginning of the excitement involved in designing a better way to do it next year. In fact, our primary interest as noted in Dave Borden's AMRAD Newsletter Packet column of July 83 was the desire to link a system of computers on packet radio to handle the data on the over one hundred horses, riders and runners so that information would be readily available at key points for emergency purposes. This paper will describe a distributed data base system implemented with Commodore 64 and VIC-20 Computers linked via amateur packet radio.
ISO Reference Model Review
by Terry Fox, WB4JFI: Abstract: This paper will review the status and positions of the various layers in the ISO (International Standards Organization) OSI-RM as applied to amateur packet radio.
AX.25 Network Sublayer Protocol Recommendation
by Terry Fox, WB4JFI: Abstract: This is the first of four papers that make up a protocol recommendation for AX.25 at Level 3A, the network sublayer. This eries of papers is being generated by AMRAD after a series of meeting between AMRAD members Paul Rinaldo, W4RI, Terry Fox, WB4JFI, Dave Borden, K8MMO, Eric Scace, K3NA, and Gordon Beattie, N2DSY. This is a first draft, corrections and ammendments will be forthcoming. Follow the AMRAD Newsletter (see information in the first paper ot this series) for further information.
Packet Formats of AX.25 Level 3 Protocol
by Terry Fox, WB4JFI: Abstract: This paper is Part two of a series of papers that describe The Network Sublayer portion of an AX. 25 data communications system. The purpose of this paper is to describe the formats of the various types of packets used to establish, maintain, and tear down a connection between a DTE and a DCE, along with the packets necessary to control the data flow along that connection while it is operational. This paper was generated by taking the CCITT X.25 document and adding or deleting nformation pertaining to amateur radio data networking. This is a first draft, corrections and ammendments will be forthcoming. Follow the AMRAD Newsletter (see information in the first paper ot this series) for further information.
Optional Facilities for AX.25 Level 3 Protocol
by Terry Fox, WB4JFI: Abstract: This paper is the third in a series of papers that make up a recommendation for the AX.25 Network Sublayer protocol. The purpose of this paper is to describe optional user facilities requested of the network or called DTE at time of a call request. Included in these facilities are standard CCITT recommended facilities, and additional amateur network facilities. The amateur facilities are suggested by the draft committee, reader suggestions or comments are invited. This is a first draft, corrections and ammendments will be forthcoming. Follow the AMRAD Newsletter (see information in the first paper ot this series) for further information.
Annex A Through F for AX.25 Level 3 Protocol
by Terry Fox, WB4JFI: Abstract: This is the fourth of four papers that make up a recommendation for the AX.25 Network Sublayer protocol. This paper contains the annexes for the previous three papers. These annexes are based on the CCITT X.25 document, modified as necessary to operate in the amateur environment. This is a first draft, corrections and ammendments will be forthcoming. Follow the AMRAD Newsletter (see information in the first paper ot this series) for further information.
An Enhanced Terminal Node Controller
by Lyle Johnson, WA7GXD: Abstract: This paper describes changes made in the Terminal Node Controller (TNC) developed by Tucson Amateur Packet Radio (TAPR) as a result of extensive field evaluation during the TAPR Beta test.
Some Thoughts on AX.25 Level Two
by Lyle Johnson, WA7GXD: Abstract: Comparisons are made between commercial packet-switching applications and the unique Amateur radio environment. Suggestions for enhancing the AX.25 Level Two protocol are given.
The OSCAR-ll Packet Experiment
by Lyle Johnson, WA7GXD: Abstract: UoSAT/OSCAR-ll contains a digital storeand-forward communications facility. This paper presents some background on the development and implementation of this experiment as well as describing its design.
A New Vancouver Protocol
by Douglas Lockhart, VE7APU: Abstract: This paper describes a new datalink protocol which is being developed by the author in Vancouver and being tested in Toronto. It is designed to replace the previous link level protocol commonly known as the 'Vancouver protocol' and it addresses all the major limitations of that protocol.
Working 'Packet' on OSCAR 10
by H.S. Magnuski, RA6M: Abstract: This paper summarizes the technical and operational aspects of trying to communicate via packet radio on the AMICON channel of AMSAT's Oscar 10 satellite. A calculation of effective throughput is made which considers factors other than the traditional Eb/No parameter.
A Packet Radio Emergency Communications System
by Bob Neben, K9BL: Abstract: We have come a long way in the use of packet radio. In the past few years we have gone from a handful of experimenters proving the particality of the concept, to hundreds and soon thousands of active Packeteers. Talking to one another to help the synergism of ideas is valuable, but the time is now to start building a viable system that will help public good.
An Application Note Describing A Low Power RS232 Like Interface
by Paul Newland, AD7I: Abstract: Radio Amateurs are beginning to make use of low-power (LP) micrprocessor systems for controllers and now have need for a LP serial Interface to connect them to other LP terminals or computers . This application note describes a LP serial interface that is compatible with conventional RS232 terminals plus the new "lap" computers that have only a "sort-of" RS232 serial interface.
Q-Call
by Paul Newland, AD7I: Abstract: This document defines a method of provldlng a Selectlve Group Cal I inq (SGC) facility on top of CCIR Rec 476-3 (AMTOR) MODE-Bc. SGC has application on 80 meters and VHF where propagatlon provides cons I stent communications . It provides a mechanism to allow a group of statlons to intercommunicate Without printing messages of other groups or andindividuals sharing the channel.
Packet Radio Software Approach - 1984 Onwards
by Robert M Richardson, W4UCH: Abstract: The future of the software approach is 'crystal balled' bv the author of 'Synchronous Pac~et Radio - The Software Approach' (Vols. 1, 2, & 3) and 'The Gunnplexcr Cookbook - A 10 GHz Microwave Primer.' Topics discussed include: - Bringing the software approach to the top of the learning curve. - New generation microprocessors influence on the software approach. - Low power requirement applications of the software approach to remote terrestrial repeaters and spacecraft. - Implementing the software approach on very low-cost microcomputers. - Future packet predictions year 2000 AD.
Packet Radio - The 3rd Generation Software Approach AX.25 Protocol
by Robert M. Richardson, W4UG: Abstract: The 3rd generation 'software approach' to 1200 baud packet radio using the AX.25 protocol is described. This approach consists of software written in assembly language to replace the Tucson Amateur Packet Radio (TAPR) terminal node controller (TNC) which includes: - the TNC's 6809E microprocessor. - the TNC's costly SDLC/HDLC controller. - the TNC's large 25K to 35K EPROM. - the TNC's dynamic RAM. - the TNC's RS232 UART - the TNC's ancillary support chipS.
A Mini-Sized Bulletin Board System Possible Standard for Packet Radio
by Robert M. Richardson, W4UCH: Abstract: AUTO connect/disconnect mode for unattended operation is available with the Vancouver Area Digital Communications Group's terminal node controller (TNC), the Tucson Amateur Packet Radio TNC, and 'Synchronous Packet Radio Using the Software Approach - AX.25 Protocol' software TNC.
Keyboard Input Message With Automatic Switching in Connected Mode and Return for Packet Radio Using Software Approach
by Robert M. Richardson, W4UCH: Abstract: A number of options open to the programmer are discussed including manual switching, using interrupts, and psuedo interrupt mode. The objective is to emulate as closely as possible the packet radio hardware approach (VADCG and TAPR TNC) which utilize their own microprocessor, ROM, and RAM plus a separate host microcomputer.
Adding Multiple Repeater Capability to Packet Radio Using the Software Approach AX.25 Vol.2
by Robert M. Richardson, W4UCH: Abstract: A breif assembly language subroutine to add multiple repeater call letter decoding within the address field of a received AX.25 frame is described.
Appendix: Direct-Printing Telegraph Equipment in the Maritime Mobile Service, CCIR Recommendation 476-3

4th Computer Networking Conference
March 30, 1985

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Sorry, ARRL 1st-4th Computer Networking Conference 1981-1985 is no longer available

This proceeding is available on CD-ROM

Location:: San Francisco, California
Coordinators:: Paul L. Rinaldo, W4RI
Dr. Henry S. Magnuski, KA6M
Hosted by:: American Radio Relay League (ARRL)

Abstracts:
4th Computer Networking Conference
March 30, 1985

Communications Protocols for the Network and Transport Layers of the Amateur Packet Network
by J. Gordon Beattie, Jr., N2DSY and Thomas A. Moulton, W2VY

Abstract: There has been much discussion among amateurs about internetworking with other areas of the country and globe. This has led to the introduction of terms into the vocabulary of many amateurs, many of whom are newly equipped with computers. In this paper, we will present the ISO/CCITT Open Systems concept and its impact on the protocols we wili be using to provide reliable data transfer in the amateur network. In order to provide a basls for contrast, we will also introduce the U.S. Department of Defense protocols.

Proposal: Recommendation AX.121NA Numbering Plan for the Amateur Radio Network in North America
by J. Gordon Beattie, Jr., N2DSY and Thomas A. Moulton, W2VY

Abstract: The purpose of this Numbering Plan is to facilitate the introduction of amateur data networks and provide for lnternetworking ln the North American region.

The Frequency Agile Message System (FAMS)
by David W. Borden, K8MMO

Abstract: With the increasing traffic appearing on local two meter packet radio channels, computer packet radio message systems appear to the casual conversationalist typer as channel hogs The message systems interfere in two modes. First, a typer user connects with it and downloads large packets of file data, help messages, directory etc. Second, a semi-automatic store and forward mode is invoked periodically to forward messages further up the network to other messages systems. The service these message systems provide more than justifies their existence, so the answer is not to ban them. A new method might alleviate the interference and retain their useful features This method involves frequency agility, the ability to switch frequencies on command, to pass traffic.

EASTNET: A Year Later
by Bob Bruninga, WB4APR

Abstract: The original goal of EASTNET to link the eastern seaboard from Washington DC to Boston was met more or less on August 6, 1984 when packets were exchanged via the repeater path WB4APR-6 in Elk Neck Maryland, WA2LQQ-O in Warwick NY, WORLI-O in Westford MA, and KD2S-l in Lowell MA. Since that time numerous alternate paths have been exercised but the saturation of the primary link frequency of 145.01 MHz during prime evening hours has prevented routine end-to-end multi-hop paths.

Packet Radio Timing Considerations
by David Engle, KE6ZE

Abstract: This Paper presents an analysis of existing packet radio systems and equipment (2 Meter AFSK). Both dual and single frequency repeater efficiencies are analyzed. The results demonstrate the relative inefficiencies of the existing networks. These inefficiencies reduce the effective capacity of a 1200 baud channel to 300-500 baud. In order to correct some of these inefficiencies a few suggestions are offered.

Of Virtual Circuits, Datagrams, and the Circular File
by Terry Fox, WB4JFl

Abstract: This paper presents s1ightly biased view of the main two types of networking concepts being discussed for amateur radio.

CCITT X.224 Transport Layer Protocol Basic Description
by Terry Fox, WB4JFI

Abstract: In order to assure absolute data integrity through the amateur network, some form of transport layer protocol should be employed between the entry and exit points of the network. In datagram service, this transport comes in two basic forms, the Transmission Control Procedure (the TCP in TCP/IP) and the User Datagram Protocol, or UDP. The UDP is a very small transport protocol, and as such does not provide absolute data integrity under all conditions. The TCP is a much more robust protocol, and as such is capable of assuring absolute data integrity through the network, with a much higher overhead.

FADCA GATOR Link 1 Packet Radio Linking Network
by Howard Goldstein, N2WX and Ted Huf, K4NTA

Abstract: The GATOR LINK 1 concept was devised in the summer of 1984 by a group of members of the Florida Amateur Digital Communications Association (FADCA) as a method of linking packet radio digipeaters into a system that would provide wide area communications without the problems involved in single frequency digipeating. It was recognized that while AX.25 Level 2 provided a means of linking digipeaters, as packet radio activity grew, it would be more difficult to use this feature because of collisions.

Modifying the Hamtronics FM-5 for 9600 bps Packet Operation
by Steve Goode, K9NG

Abstract: Within the last year considerable attention has been given to level three linking of local area packet groups across the country. Experiments Using virtual and datagram circuits are under discussion. This paper presents an interface board and the necessary modifications to the Hamtronics FM-5 220 MHz transceiver allowing operation at 9600 bits per second (bps) to provide a high speed link between the local area networks.

Packet Radio for Distance Teaching in the Third World
by Phil Gray, KA7TWQ

Abstract: How Packet Radio could greatly improve the intersctive capabilities of Distance Teaching. Some views on how Packet Radio could improve the delivery and efficiency of Distance Teaching in Less-Developed Countries.

Packet Radio Development - 1985
by Lyle V. Johnson, WA7GXD

Abstract: A review of packet growth since the Third ARRL Networking Conference is followed by a discussion of anticipated expansion of packet activity during the next year. A framework for orderly growth is presented, based on the above observations.

Packet Radio and the National Hurricane Center
by Joel I. Kandel, KI4T

Abstract: Amateur radio operators in South Florida are exploring the capability of Packet Radio to provide the National Hurricane Center with high quality weather observational data, and in turn transmit timely forecast information from the Hurricane Center to effected areas.

TCP/IP: A Proposal for Amateur Packet Radio Levels 3 and 4
by Phil Karn, KA9Q

Abstract: This paper presents a case for basing Level 3 (the network layer) of Amateur Packet Radio on trhe datagram concept. It further proposes that the DARPA protocol IP (Internet Protocol) and TCP (Transmission Control Protocol) be adopted intact as the standard Level 3 (Network) and Level 4 (Transport) protocols for Amateur Packet Radio. I will then provide an overview of TCP/IP, explain why it, as a datagram protocol, is more suitable for our needs than the virtual-circuit protocol CCITT X.75, and show how it would be used above the AX.25 Level 2 protocol already in use.

Addressing and Routing Issues in Amateur Packet Radio
by Phil Karn, KA9Q

Abstract: As amateur packet radio evolves from scattered, ad-hoc collections of local area digipeaters into a large, auitomatic, and interconnected network, several issues related to naming, addressing and routing will have to be faced and overcome. Routing in particular, has long been a fertile research area in computer networking. I make no claim to knowing the answer to many of these problems; however, I believe that they can at least be stated, and that certain decisions can be made early to ease experimentation with various solutions. In particular, the problem of address assignment is discussed with particular emphasis on making the routing problem easier.

X.3 and X.28 Protocol for Terminal Node Controllers
by Douglas Lockhart, VE7APU

Abstract: This paper proposes the adoption of an extended version of CCITT recommendations X.3 and X.28 for use in Amateur radio Terminal Node Controllers. The various X.3 parameters and X.28 commands and service signals (messages) are outlined and the extensions in place in the V-2 software implementation on the VADCG (Vancouver Amateur Digital Communication Group) TNC are discussed.

Formal Definition Meeting for the Packet Radio Experiment RUDAK to be Included in AMSAT P3-C
by Dr. Karl Meinzer, DJ4ZC and Hans Peter Huklen, DRlYQ

Abstract: During the weekend February 15 thur 17, AMSAT-DL hosted a formal meeting to define the Packet payload in PS-C. The experiment has been name "RUDAK" for "Regenerativer Umsetzer fur Digitale Amateur-Kommunikation".

A More Watchful Watchdog for Microcomputers
by Paul Newland, AD71

Abstract: Many hardware/software watchdog timers consist of a software routine that repetitively triggers a hardware retriggerable monostable. If the monostable ever times out, the computer is reset. This technique, although useful, is not extremely reliable under most software/hardware insane conditions. This paper discusses an alternative approach that may prove to be more reliable under various fault conditions.

A Few Thoughts on User Verification Within a Party-Line Network
by Paul Newland, AD7I

Abstract: This paper presents an idea for verifying that a user within a party-line network is who he or she claims to be. The idea assumes that the channel is a party-line and that potential intruders will monitor authorized communications and may attempt to masquerade as authorized users. No attempt is made to encrypt the authorized user's data for transmission over the party-line.

Another Application Note Describing a Low-Power RS232-Like Interface
by Paul Newland, AD7I

Abstract: A new and improved low power RS232like interface is discussed. It features half the power consumption of the interface presented in a previous paper and uses fewer parts.

The Realities of Packet Radio in the Amateur Radio Service, circa 1985 - or - How to Deal with a User Base
by Harold E.Price, NK6K

Abstract: The author postulates the existence of two major experimenter groups in amateur packet radio; those who experiment with data sent via packet radio and those who experiment with the way data is sent via packet radio. The problems of these groups in the face of 5000 or more packet users by the time of the 5th ARRL networking conference are discussed.

Let me preface this discussion by noting that some of the thoughts presented here were the result of group discussions during a meeting of the ARRL Ad Hoc Digital Communications Committee in 1984. At that meeting, the major discussion was layer three networking.

The Implications of Traditional Operating Practices for Amateur Packet Network Design
by Gwyn Reedy, WlBEL

Abstract: Amateur packet network design relies heavily upon equipment and procedures developed for commercial service. This paper urges network designers to examine the anticipated uses of the network by amateurs, and modify commercial practice to accommodate the existing amateur population.

AX.25 Net Operation in the Connected Mode Using the Software Approach
by Robert M. Richardson, W4UCH

Abstract: This brief paper presents the means whereby an amateur radio net may be conducted using the AX.25 packet protocol with all stations in the connected mode. Use of a net control station connected simultaneously to all members of the net is described as well as window overlays on the video displays of all members of the net to display other net members packet information fields.

Computer Networking in Japan 1985 - Onwards and How Bill Gates' (Microsoft) Created the Far East and Pacific MSX Standard
by Robert M. Richardson, W4UCH

Abstract: The evolution, development, and implementation of the Microsoft MSX operating system in nearly 2 dozen models of microcomputers now being manufactured in the Far East and Pacific (FEP) is discussed alons with their impact on packet radio on the amateur bands primarily in Japan, for the 1985 - onwards, time frame.

Activity Report of PARNET
by Tskemi Yamazaki, JAlMIR, Masahiro Takeda, JA3FGN, Notokazu Kashida, JHlUWU, Masa-aki Yonezawa, JElWAZ, and Tadanori Harada, JI1BXM

Abstract: We have been studying and working on digital communications in ham radio for the past year. The group activities are discribed in this paper. In section one, there are member's profiles, group's aim/policy and results of our investigations. In section two, the hardware of the prototype is described. In section three, the software descriptions and in section four, prospect in the future is written.

Appendix 1: Amateur Packet Radio in Region 3
by Paul L. Rinaldo, W4RI

Appendix 2: GATEWAY, The ARRL Packet Radio Newsletter - all available issues up to the time this anthology, ARRL