ARRL Certification Program
Emergency Communications
JNOS and TCP/IP Packet E-mail Systems

• STRENGTHS:
1. The hardcopy messages provides accuracy when dealing with long and complicated messages.
2. The messages appear in hardcopy, making it instantly available to be photocopied and handed out.
3. For long messages, packet messages can be sent and copied faster than voice messages.
4. Messages are received, forwarded and printed automatically without the need for operators.
5. It has very good signal detection at 1200 baud when compared to FM voice.  A TNC2 will pull out a full copy digital signal when it is barely audible on voice.
6. When engineered correctly, a packet network has a high level of service.
• WEAKNESSES:
1. Requires computers and continuous emergency power to operate.
2. Requires computer literate people to install and configure the equipment.
3. Requires packet literate people to install and configure the equipment.
4. Requires all participating systems to use using the same software and methods.
5. The communications channel can get congested if other stations randomly enter the network, resulting in a poor quality of service.
6. Messages that need to be rerouted to another network are not automatically detected and rerouted as it would be for a voice network

1. Need to identify the communications requirements.
2. Need a corp of trained operators and technicians.
3. Need to identify the sites capable of hosting a pilot system.
4. Need to advance the word to institutions for budgeting and planning purposes.
5. Need to advance the word to packet amateurs.
6. Need to determine operating procedures.
7. Need to determine frequencies.
8. Need to deal with the effects of intermod interference.
9. Need to determine a typical station configuration.
10. Need to make adjustments for the agency message desk and messaging due to the expected volume of messages.
11. Need to define methods of expanding the system to cover rural and outlying areas not well covered by packet.

 

1. Committed personnel for the respective agencies served will need to be selected, trained and available to serve as packet operators/technicians.  Operators that are not involved and not responsible for the agencies have less weight in the success of the project.
2. Need a critical mass of knowledgable, active hams.
3. Target the important agencies with a clear need.
4. Each agency to send their amateur representative to the packet technical meeting.

 

1. Insist on a minimum level of performance (power and receiver) so everyone will hear everyone else to avoid collisions (could micro cell to a

backbone);
2. the system must be capable of unattended hard copy on a printer;
3. the system must be capable of storing messages if the end node is down;
4. send immediately vs. query on schedule;
5. message destinations not covered would include:
• individuals
• any agencies not built into the network
• connections may be possible due to line of sight coverage, but not to the point of bringing down the system.
• skill level of the available hams, attrition and their availability should be considered;
6. The preference would be to send a written message or to interact verbally about a message. Interacting verbally gives the opportunity to qualify the statement, permiting clarifications and substitutions to better convey the information. The recipient would normally like to qualify or clarify the message before taking action on the information. This is especially true for strategic information.
7. For medical messages, due to the technical, specific nature of the medical industry, names of medical supplies and medications should be written down. For tactical information between institutions, complicated information should be delivered in a written, hardcopy format.
8. Updates to the stratetic and tactical information would occur regularly, usually at a minimum of hourly intervals. Lengthy written tactical communications can occur at any time.

 

1. It is a TCP/IP oriented e-mail system.  If you're familiar with Internet e-mail, you're familiar with typing e-mail into JNOS.
2. It has the ability for the operator to open up to eight windows for messaging.  It has a ninth window for command mode, and a tenth window for debugging.
3. It will print incoming messages automatically onto a printer, unattended.  If the printer is a cut-sheet printer such as a HP Laserjet printer, individual messages will automatically appear on separate sheets.
4. It sends e-mail via SMTP mail protocol and can interface to Internet.  A JNOS station can relay packet radio messages to the Internet and vica versa unattended.
5. It supports multiple communications ports and multiple radio/TNC combinations.
6. Its shareware.  It runs on MS-DOS and Linux.
7. It can multitask efficiently on a 386 computer with 1MB memory.  In a minimal configuration, it can run on a PC/XT (640KB 8086) as an end-node station.

 

The design analysis for a two-way packet messaging system is based on these premises:
 

1. The most important factor is to minimize collisions.  This was confirmed that in every exercise, where excessive collisions and congestion proved to defeat every packet system tested and it was not specific to a particular software. This is obvious by inspection, but cannot be underemphasized enough in the analysis process.
2. If the objective is to eliminate throughput problems associated with digipeaters (and hidden transmitters), that discrete simplex frequencies and digital repeaters should be used to reduce congestion due to packet collisions.
3. This implies that the PC software performs message or packet routing between the frequencies.
4. When a radio link fails, either the PC software must detect and make an automatic change to the routing tables, or a person must intervene and manually update the routing tables. This implies that a ham must be on-site and trained to assess and perform these changes, and this is where the bulk of the human "wetware" problem lies. This "problem" is actually an improvement over commercial radio systems, as trained and equipped technicians are unavailable to staff each potential agency to workaround incremental equipment failure.
5. The changes to the routing tables can be previously assessed and proceduralized. A person can then look up the changes and implement them. The person would need to be trained on how to implement these changes.
6. (It was not stated in the meeting, but the implication is that these procedures are valid for a single failure of a radio link in the network, and it may not be valid if multiple links fail. This will have be kept in mind during the development of the error recovery procedures.)

 

 
1. The first preference is to use the frequency bands above 222 Megahertz. The two meter band is congested with existing voice and data activity which could lead to interference from adjacent channels. The UHF paging transmitters at the hospitals also generate substantial interference.
2. The 220 band is untapped and would prevent many of the above undesirables from interfering. It has propagation similar to the two meter band.

The 219 MHz band is available. It is a 10 100 KHz data channels, a shared radio service, coordinated by the ARRL, for point-to-point stations, not more than 50 watts output. Useful for long-haul linking.
3. 56Kbps modems are available, the most widely used is the WA4DSY modem, which can be put on any band above 219 with the use of transverters from Down East Microwave or similar outfits. Paccomm features the WA4DSY modem.
4. See: http://www.paccomm.com/

http://www.acs.ncsu.edu/HamRadio/News/newsline.925.html
http://www.acs.ncsu.edu/HamRadio/News/newsline.966.html

• PC Hardware
• Required
1. Runs on a minimum platform of an Intel 386, 1 Megabyte RAM, 40 Megabytes Hard Disk, one serial port for TNC, one parallel port for printer.
2. Supports HP inkjet, Canon Bubblejet and/or HP Laserjet cut-sheet printers.
• Desired
1. Supports a second serial port for another TNC.
2. Supports a third serial port for a dial-up modem.
3. Supports an Ethernet LAN card.
4. Supports Windows 95.
5. Optionally supports LINUX.
• PC Software
1. Highly stable software capable of operating two weeks without rebooting.
2. Supports TAPR TNC2 standard command set.  Optionally supports KISS interface.
3. Supports AX.25 protocol.  Optional support for G8BPQ, IP, NETROM, X14J and/or ROSE protocols
4. Supports unattended printing of inbound messages.
5. Shareware or freeware desired.
6. Active base of support on Internet newsgroups and Web sites.
7. Optionally runs in Windows 95.
8. Optional support for Ethernet LAN attachment.
9. Optional support for dial-up modems.
10. Optional support for fax modems.
11. Optional support for multiple printers.
• TNC/Modem
1. Minimum of TAPR TNC2 with 1200 baud modem.
2. Supports KISS mode.
3. Optional support for 9600 baud modem.
4. Optional support for Pactor and G-TOR.
• Radio
1. Supports a minimum of 1200 baud AFSK.
2. Runs off of 13.6 volts DC.
3. Frequency band to be determined.
4. May be cross-banded.
5. Provides a minimum power output of 5 watts at 50% duty cycle.
6. Optionally supports 9600, 19.2K and/or 56K baud.