H4 ARQ Progress report.
I have been busy completing the H4 ARQ mode. I uploaded the current spec (rev 0.3.1) which is now quite complete (10 pages) including all protocol rules, Frame descriptions and State diagrams for both FEC and ARQ modes. It is a pdf on the Yahoo FTP server titled H4 FEC and H4 ARQ Protocol Spec. Reading the spec may be helpful if you are having trouble falling asleep! Having a good and detailed spec made the coding effort move along much faster and will be essential to anyone trying to port the VB.NET source code to another platform. (I don’t plan on posting the sources until out of beta testing).
I have virtually all the ARQ code completed and am starting testing locally (across the desk). (Of course there were many short tests during code generation but with an ARQ system you can’t get too far without all the code in place and having two systems to talk to each other!). The implementation is clean and should work out well. I have the binary transfer option coded in the TNC but that won’t be enabled on the first release. (it will allow sending a named binary file in ARQ mode…with compression). I have tried to make the protocol as efficient as possible (running at about 66% of the FEC max rate which is pretty good as ARQ protocols go). An ARQ session can also be “monitored” by a user in FEC mode (with “clean” text printout…suppressing all the CRCs and frame ID characters) but can’t of course correct all errors that the ARQ connection can. There are provisions for calling CQ in ARQ mode and a single mouse click to answer a CQ. It is also possible to call a specific station of course.
I expect to have something worthy of an alpha release in a week or perhaps 2. (remember alpha has bugs and should not be used by those without debugging skills!) The FEC mode will be essentially the same as the current H4 FEC mode now on the FTP site. The objectives initially are to debug the ARQ mode and evaluate its robustness etc. Bells, Whistles, Frills and Fluff won’t be added until the basic ARQ mode is solid.
Rick Muething, KN6KB
UFB! We wait alpha version to test it with feedback reports by old "GruppaOHdigi" in Finland by OH5RM OH7JJT OH7TE on HF and 50 MHz
73 OH7TE/5 "Yussuf" S-E Finland loc KP30JS
>Cant wait to try it out :-)
> I expect to have something worthy of an alpha release in a week or perhaps
> 2. (remember alpha has bugs and should not be used by those without
> debugging skills!) The FEC mode will be essentially the same as the
> current H4 FEC mode now on the FTP site. The objectives initially are to
> debug the ARQ mode and evaluate its robustness etc. Bells, Whistles,
> Frills and Fluff won't be added until the basic ARQ mode is solid.
Maybe before xmas?!?