<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">As a fairly new ham and APRS user (and now digi/igate operator), I've noticed that a stated goal for APRS is somewhat conflicting. <div><br></div><div>Take, for example, the statements (from <a href="http://aprs.org">aprs.org</a>): "<span class="Apple-style-span" style="font-family: Times; ">APRS is not about <i>vehicle tracking</i>. It is a single <b>information resource</b> channel <span class="Apple-style-span" style="font-family: Helvetica; ">", "<span class="Apple-style-span" style="font-family: Times; ">APRS is not about dumb-one-way-trackers. <span class="Apple-style-span" style="font-family: Helvetica; ">", and "<span class="Apple-style-span" style="font-family: Times; ">And finally, that all mobiles would have simple displays to keep them in communicaitons and aware of their surroundings.<span class="Apple-style-span" style="font-family: Helvetica; ">"</span></span></span></span></span></span></div><div><br></div><div>This implies 2-way communication. Yet, elsewhere on <a href="http://APRS.org">APRS.org</a> the solution for "dead zones" in the APRS network is a "wide1-1" digi - documented as:</div><div><br></div><div><span class="Apple-style-span" style="font-family: Times; "><pre style="word-wrap: break-word; white-space: pre-wrap; ">WIDE1-1 fill-in digis provide a way for mobiles in a dead zone to be
able to be digipeated out without that same digipeater adding to the
congestion elsewhere by also digipeating every other packet heard from
everywhere else. In otherwords, it only responds to 1st hop packets
from mobiles and/or stations that explicitly use the WIDE1-1 hop first
in their path. </pre></span><div><br></div></div><div>This is in direct conflict with a stated goal of 2-way communication, as the "fill-in" is only repeating packets FROM the mobile station, and wouldn't repeat TO that mobile station any packet (unless it happened to have an unused WIDE1-1 hop specified in its path - which is unlikely.)</div><div><br></div><div>If the mobile can't talk to the major WIDE2 digi's in the area, they likely can't "hear" them either. The WIDE1 "fill in" digi, in this case, only serves to support "dump-one-way-trackers" and does nothing to facilitate 2-way communication between the station in the dead zone and the rest of the APRS network. </div><div><br></div><div>There are other areas that I found conflicting as </div><div><br></div><div>To this end, I really like what aprx is doing with the experiment of "viscous digitpeating." This seems to be a BETTER solution to black holes than the above mentioned "fill in" digi's (which are nothing more than "dumb-tracker" relays.) It doesn't completely solve the problem, as the aprx digi can't know if a local mobile can hear other digi's, but I think its a step in the right direction. </div><div><br></div><div>Take care</div><div>Gary / K3WOW</div><div><br></div><div><br></div><div><br></div></body></html>