--- In dstar_digital@yahoogroups.com, Nate Duehr <n...@...> wrote: > > On 4/7/2010 4:40 PM, Nicholas wrote: > > > > I may be asking a question that has already been answered. What is the > > difference between Linking (UR: KJ4MMCCL) and Source Routing (UR: > > /KJ4OXTC)? This is something I have yet to figure out. > > > > Thank you and 73s, > > Nick KF4SEK > > Cocoa, FL > > > Quite a bit. > > Source routing is a one-shot route... you key up and the system routes > that single transmission to the person's last known location. You get > confirmation that it routed all the way to the far end gateway server, > back in your radio. "UR" vs. "RPT" displayed after each transmission. > It's the "original" Icom design. It's also the only way to talk across > Trust Server networks to the Japanese system. They do not have... (see > below...)... > > Linking is provided to D-STAR on the U.S. Trust Server network by the > D-PLUS add-on software, and isn't built-in by default to Icom's Gateway > software. Once you issue the command, you and everyone else (you switch > back to "CQCQCQ" for your UR field after this type of "hard" link is > established between two repeater modules, or a repeater module and a > reflector channel) who talks on the local frequency is heard at the far > end until the link is terminated. You get no confirmation that your > transmission was transmitted end to end, but it's the only GOOD way to > do point to multipoint linking. > > Icom DID provide a system that allows for Source Routing point to > multipoint, called "Multicast" (not to be confused with IP network > Multicast, which is a different thing altogether). It requires that all > of the participating Gateway operators set up a specific fake "callsign" > that all users "route" to, and every Gateway must be both programmed to > send that callsign's traffic to all other repeaters in the group, and > also must have enough bandwidth at the repeater site to send that many > streams... each repeater in the multicast list gets its own stream. > Haven't really played with this one, but in practice, the bandwidth and > other limitations make it pretty "wimpy" compared to nice high-bandwidth > Reflector server and D-PLUS. > > In practice, both work pretty well, but for calling CQ and general > rag-chews, D-PLUS linked to a Reflector is probably the easiest way to > do that. Direct Source Routing works best for finding an individual... > or perhaps routing to your own radio at home when doing something mobile > with low-speed data (as long as you have two Terminals registered, and > the rig's "Your Call:" is programmed appropriately so the system sees > them as two completely different end-points... especially if you don't > know where they are, and they don't bounce around repeaters too much. > (Source Routes are only updated slowly in the national database, so > "chasing" someone from repeater to repeater using only their callsign, > usually doesn't work too well. They're based on the last repeater > module the person keyed up on... Example... if I fly from Denver to > Hawaii, and key up there... you source routing to me would still work if > I made sure to key up 5-10 minutes before your call in Hawaii...) > > Hope that helps... > > Nate WY0X >
Nate, Thank you for clearing it up for me. It is perfectly clear now. 73s, Nick KF4SEK
