<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body>From reading the specs, the generic and New-N paradigm digipeating aren't documented anywhere in the AX.25 specifications. AX.25 Version 2.2 is so old, it predates RELAY and WIDE, let alone the New-N paradigm. And would connected-mode packet work reliably with redundantly responding digipeaters?<div><br></div><div>So any spec would have to clearly note that generic digipeating and its successors of New-N, viscous, and preemptive digipeating do not apply and should not be used for I and S frames (and possibly not for other subtypes of U frames besides UI), aside from the issue of deprecating 1st generation generic digipeating (RELAY/WIDE/TRACE).</div><div><br></div><div>Your webpage seems to be a good starting point for 2nd gen generic digipeating.</div><div><br></div><div>Andrew, KA2DDO</div><br><br>-------- Original message --------<br>From: Robert Bruninga <bruninga@usna.edu> <br>Date: 1/5/17 3:18 PM (GMT-05:00) <br>To: TAPR APRS Mailing List <aprssig@tapr.org> <br>Subject: [aprssig] Documenting the APRS Generic Digipeating spec? <br><br><div class="WordSection1"><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">APRS Authors:</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">We all came up with the “Generic-digipeating” concepts for APRS in 1995 or so and is pretty well established in most modern TNC’s </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">But its been so long and maybe I am having a senior moment, but I am drawing a blank in trying to think where it is actually documented in AX.25!?? The APRS spec only addresses the data formats (and the use of the AX.25 Destination callsign field in its non-standard way). The APRS spec (I don’t think) addresses any of the generic digipeating techniques used.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">I think we need to nail this down by spec, since there are some weird implementations that cause confusion. And if there are new ideas we want to add, then we should have a documented baseline starting point.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">We could call it AX.25-UI for clarification.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">My source for how this all works is my decade old <a href="http://aprs.org/fix14439.html">http://aprs.org/fix14439.html</a> web page.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Is there another better starting point for extracting exactly what UI digipeating is?</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Or am I having a senior moment?</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Bob, WB4APR</span></p></div></body></html>