Posted on behalf of Martin Rothfield W6MRR who is having an issue posting a comment:
Power/modulation/data rate/processor are all mentioned but not the media access layer (MAC) method. The popular ham ad-hoc/mesh networks - Meshtastic and AREDN share CSMA (slotted Aloha or CSMA RTS/CTS) and pay the penalty. There is no reason to max out with just a fraction of channel bandwidth. TDMA allows (almost) full channel capacity with very little jitter. TDMA ad-hoc/mesh networks are possible but take more work. What is on the roadmap?
Replying to Martin W6MRR from my (N8GNJ) perspective. I hope Martin VE6VH replies with his perspective.
"CSMA / CD" is what IP400 will initially use... with some considerable enhancements. For one, every IP400 station will beacon about itself, and beacons will be aggregated and repeated by adjacent station. Thus each IP400 station will have a pretty reasonable, and reasonably dynamic "map" of the network. For example, if an adjacent station's "aggregation" includes a station that isn't heard directly, traffic for that station will automatically be relayed rather than being attempted to connect directly.
Some other differentiating features of IP400:
* With ample spectrum in 420-450 MHz (and eventually, other bands) it won't be unusual for an IP400 station to consist of multiple radios on different frequencies, and eventually, different bands.
* I think that it will be possible to monitor much of an entire band simultaneously (ka9q-radio technology). Thus it might be feasible to implement something like "slow frequency hopping" - monitor a number of local "IP400 channels" and transmit on one of those randomly because any IP400 transmission will be received (by the ka9q-radio receiver).
* Eventually IP400 will involve VHF / UHF repeaters
* Or even more interesting, a hybrid TDMA approach, if a IP400 repeater is operating in your area, the repeater can listen to the local "IP400 channels" and transmit a continuous status of which IP400 channels it sees in use, and not in use, which will minimize collisions.
With fast data speeds, lots of spectrum on VHF / UHF, and the potential involvement of repeaters, there's a lot of new things we can do, and especially that we can experiment with. I can easily imagine "It's Saturday - download the test mode of the week; run the automated test suite for 6 hours and upload your testing log".
Posted on behalf of Martin Rothfield W6MRR who is having an issue posting a comment:
Power/modulation/data rate/processor are all mentioned but not the media access layer (MAC) method. The popular ham ad-hoc/mesh networks - Meshtastic and AREDN share CSMA (slotted Aloha or CSMA RTS/CTS) and pay the penalty. There is no reason to max out with just a fraction of channel bandwidth. TDMA allows (almost) full channel capacity with very little jitter. TDMA ad-hoc/mesh networks are possible but take more work. What is on the roadmap?
Replying to Martin W6MRR from my (N8GNJ) perspective. I hope Martin VE6VH replies with his perspective.
"CSMA / CD" is what IP400 will initially use... with some considerable enhancements. For one, every IP400 station will beacon about itself, and beacons will be aggregated and repeated by adjacent station. Thus each IP400 station will have a pretty reasonable, and reasonably dynamic "map" of the network. For example, if an adjacent station's "aggregation" includes a station that isn't heard directly, traffic for that station will automatically be relayed rather than being attempted to connect directly.
Some other differentiating features of IP400:
* With ample spectrum in 420-450 MHz (and eventually, other bands) it won't be unusual for an IP400 station to consist of multiple radios on different frequencies, and eventually, different bands.
* I think that it will be possible to monitor much of an entire band simultaneously (ka9q-radio technology). Thus it might be feasible to implement something like "slow frequency hopping" - monitor a number of local "IP400 channels" and transmit on one of those randomly because any IP400 transmission will be received (by the ka9q-radio receiver).
* Eventually IP400 will involve VHF / UHF repeaters
* Or even more interesting, a hybrid TDMA approach, if a IP400 repeater is operating in your area, the repeater can listen to the local "IP400 channels" and transmit a continuous status of which IP400 channels it sees in use, and not in use, which will minimize collisions.
With fast data speeds, lots of spectrum on VHF / UHF, and the potential involvement of repeaters, there's a lot of new things we can do, and especially that we can experiment with. I can easily imagine "It's Saturday - download the test mode of the week; run the automated test suite for 6 hours and upload your testing log".
Discussion moved to the IP400 email list - https://groups.io/g/ip400