A Proposal for a Wireless Internet of Portable Nodes (WIPNet)

by Jon Roland KC5MYS jon.roland@constitution.org



The prospects that the Y2K problem, or other such cascade failure arising 

from other causes, might bring down power grids and telecommunications 

systems, suggests that we consider establishing an alternative 

communications system that could support emergency services in such an 

event.



One of the main ways that emergency communications has been provided in the 

past is through amateur radio networks. However, the advent of packet radio 

and other forms of digital communications on amateur bands suggests a better 

use of the bandwidth, especially since a nationwide or worldwide failure of 

essential systems would be likely to overwhelm the ability of traditional 

amateur voice communications to cope with the situation.



A number of amateur and commercial researchers have been exploring expansion 

of the Internet to radio links, using the TCP/IP and AX-25 protocols and 

making use of both the amateur bands and the newly available spread spectrum 

bands. These are represented by such efforts as FlexNet and AMPRnet, and 

such services as Ricochet. See http://constitution.org/wipnet/wipnet.htm



This is to suggest that we get together to establish a much more ambitious 

system. The effort is complicated by the need to confine the use of amateur 

bands to licensed amateurs, which is not a limitation for the use of spread 

spectrum bands. The following are the design specifications for such a 

system.



- All nodes would be portable computers and transceivers. There would be no 

wired backbone, although there could be connections to the wired backbone to 

make use of it, if it is available, such as to span what would otherwise be 

breaks in the network.



- The geographic range of the system would be nationwide or worldwide. Any 

node would be able to send an email message to any other anywhere on the 

network, regardless of the number of hops in between. There would also be 

support for newsgroup, ftp and WWW services, but these might be restricted 

in the event of an emergency.



- The primary bands would be spread spectrum, with perhaps some use of HF 

bands for longer distances, to span breaks in the network.



- The addressing and routing scheme would permit all nodes to move about 

freely, and perhaps rapidly, without every node having to have a complete 

database of every node and its location, although such a database might be 

available on some nodes, making them DNS servers.



- There would be a priortization protocol to permit high priority messages 

to have routing priority over lower ones.



There are many advantages to the use of spread spectrum. It supports higher 

bandwidths, makes more efficient use of a given band, and provides better 

security. At the moment its use is limited to the 900 MHz and 2.4 GHz bands, 

and to 1 W, but amplifiers are available for use outside the U.S., and we 

can expect that use at higher powers would be excusable in the event of a 

national emergency, as would the use by non-licensed personnel. A protocol 

would have to be adopted for exchanging sequence codes among cooperating 

transceivers, but PGP-encrypted messages on a standard contact sequence 

could be used for that and for authentication of the nodes. It would also be 

better suited for preventing packets from going astray.



It would be possible, in principle, for nodes within range of each other to 

update one another's link databases, and for those databases to be 

transmitted to other nodes to update their, on a continuing basis, so that 

every node would maintain an updated database of every node and which was in 

range of which other, however, this would involve too heavy an overhead. A 

different approach would be for each node to transmit its approximate grid 

location, either set manually or taken from GPS, and messages routed along a 

node path that would take them in the general direction of the target node 

until a link was established.



The line-of-sight range of both VHF FM and SS is about 20 miles, under good 

conditions, and using antennas that could be carried by a person. That means 

that to establish a nationwide network, and to provide sufficient bandwidth 

for heavy message traffic, there would need to be a fairly dense positioning 

of nodes not more than 20 miles apart, and preferably closer, across the 

country. This could be a problem in some of the Western states, especially 

desert country, where population density is low, but in an emergency 

node-bearing operators could scatter themselves and position themselves to 

make sure that coverage was complete. Three or four operators in each of the 

3000 counties in the United States might be sufficient.



Small notebook or wearable computers with large disk drives are now becoming 

available, and they should soon become fairly inexpensive. SS 1 W 

transceivers are also becoming available at a cost of about $200 each. The 

only other things that would be needed would be power packs, a good antenna, 

and perhaps extra disk drive capacity, all of which could be carried by an 

operator in a backpack.



The importance of portability must be emphasized. In an emergency, the 

availability of fuel to operate a vehicle cannot be assumed, although 

vehicle based mobile systems might be made use of if available. But 

operators should plan on being able to operate on foot, perhaps using solar 

cells to recharge their batteries. The operator will also have to carry 

water, food, medical, and other survival supplies on him, so the 

communications equipment needs to be as small, light, and easy to use while 

on the move as possible.



The military has such systems, but, typically, they are too expensive for 

civilian use. Indeed, they are too expensive for widespread use by the 

military, which is why we cannot depend on military or national guard 

personnel to provide such services in an emergency. This needs to be a 

civilian, autonomous system that is not under central authority or control, 

like the Internet itself, and that therefore cannot easily be interdicted or 

interfered with by anyone.



We need to vigorously pursue the development, testing, and deployment of 

such a system, with the goal of full deployment not later than October, 

1999. Comments for ways to do this are welcome.