I wonder under the new rules, if waveforms such as STANAG HF modems (1200/2400/3600 bps) would be permitted in the hf ham bands? They take up an entire SSB (3 KHZ) channel. The spec is public.
TCP/IP has one important aspect that limits its usefulness for ham radio: It is extremely "chatty" - both in data volume and lots of "ping-pong". The smallest IPV4 packet is 48 bytes long and you need to acknowledge received packets on no more that 1500 bytes all the time. IPV6 certainly does not improve in this respect. So forget it for example over QO-100.
There are alternative methods, especially for store & forward applications like emails. FIDOnet showed that 50 years ago with 1200 bit/s modems over expensive phone lines. For example, one node aggregated 100 or more mails into a single, compressed file destined for another, directly connected node. Then this file was transferred with a minimum of handshake activity. The receiving node retrieved the single emails and acted on them accordingly.
Steve, thanks for the reply. The actual spec I was interested in is STANAG 4285. That’s the implementation I am familiar with. I see from the attached link it is spec’d at 3 KHz so it is a little too wide for ham use. See Page A-3 section 4 of
I wonder under the new rules, if waveforms such as STANAG HF modems (1200/2400/3600 bps) would be permitted in the hf ham bands? They take up an entire SSB (3 KHZ) channel. The spec is public.
http://www.n2ckh.com/MARS_ALE_FORUM/s4285.PDF
TCP/IP has one important aspect that limits its usefulness for ham radio: It is extremely "chatty" - both in data volume and lots of "ping-pong". The smallest IPV4 packet is 48 bytes long and you need to acknowledge received packets on no more that 1500 bytes all the time. IPV6 certainly does not improve in this respect. So forget it for example over QO-100.
There are alternative methods, especially for store & forward applications like emails. FIDOnet showed that 50 years ago with 1200 bit/s modems over expensive phone lines. For example, one node aggregated 100 or more mails into a single, compressed file destined for another, directly connected node. Then this file was transferred with a minimum of handshake activity. The receiving node retrieved the single emails and acted on them accordingly.
Steve, thanks for the reply. The actual spec I was interested in is STANAG 4285. That’s the implementation I am familiar with. I see from the attached link it is spec’d at 3 KHz so it is a little too wide for ham use. See Page A-3 section 4 of
http://www.n2ckh.com/MARS_ALE_FORUM/s4285.PDF
Bob wm6h