<html><head></head><body><div class="yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div dir="ltr" data-setdir="false">Back in the day, the protocol working group realized the importance of assuring that the protocol would be sustainable into the future.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">To that end, open the protocol document and look up "User Defined Data Format". By abiding by it, you can encapsulate all sorts of new stuff into an existing datagram and by doing so, you assure nothing is broken when being transported through IGates or the APRS-IS.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">It is a huge win, and a real testimony to the working group's future vision (waaaay back in 2004). Bravo to them!<br></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Ev, W2EV</div><div dir="ltr" data-setdir="false"><br></div></div></body></html>