[aprssig] EchoLink APRS-IS Ojbects Mothballed

Lynn W. Deffenbaugh (Mr) ldeffenb at homeside.to
Thu Jul 23 23:47:44 CDT 2009

Tim Cunningham wrote:
> Think of it as an on demand system where the user requests information 
> in their specific area, the server sends an ACK back to the requester 
> to stop the redundancy, and also transmits the Echolink Object back 
> through the path of the requester until the ACK is fulfilled. This 
> allows all in the area of the requester to see the available Echolink 
> Objects as well. No more bandwidth is utilized than what is sent on 
> demand. The requester hopefully gets the data as well as other 
> listeners in the return path of the requester. This method should not 
> flood the entire network by keeping the requested data local to the 
> requesters digi path and IGate. The down side is the requesters local 
> IGate must allow objects to pass back through the RF path when dealing 
> with filtered ports on the APRS-IS. Unless the IGate's that use 
> filtered ports modify their filter, these object packets could be 
> blocked.
Interesting idea, but it won't work within the current APRS 

1) "back through the path of the requester" - the only thing that does 
this currently is a message directed to a station that an IGate 
considers to be local

2) "hopefully gets the data as well as other listeners" - If we use 
messages to the requester, yes, hopefully s/he'll get the answer.  
Others will certainly hear it, but it's up to their client software to 
determine if they actually see messages addressed to other calls.

3) "IGate must allow objects to pass back" - That was one of the major 
objects to injecting the objects into APRS-IS.  They would only get out 
to local RF when/if IGate operators configured them to.  Some caring 
IGate operators may be inspired/persuaded to gate specific objects to 
RF, but I don't know of any that will configure to gate all objects to RF.

I'm still considering a query server to allow individuals to ask for 
"nearby" EchoLink information to be sent back to them via APRS 
messages.  It won't be tomorrow, it may not be next week, but I'm hoping 
to get to it sometime.

Lynn (D) - KJ4ERJ

More information about the aprssig mailing list