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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi Guus,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>while checking the source code, I stumbled upon PMTU Discovery.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I’ve got a question regarding the process of sending/receiving PMTU packets.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>As I understand, the packet flow is like this:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>1 .Tinc creates a packet with a specific payload length to send it as an PMTU probe.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> (The data part is just some random bytes.)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>2. This packet gets compressed and sent over UDP.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>3. The packet is received from the other node and gets decompressed.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>4. The uncompressed length of the packet is taken as MTU value.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>My question is, whether it is reasonable to compress a PMTU packet, since the payload length, that gets transferred over the wire changes.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>In my opinion, tinc must not compress the PMTU packet to keep the original length as desired for probing.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Best,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Daniel<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>PS: As you may have noticed, I am still developing the multicast/local part.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>As soon as I’ve fixed the errors, I’ll try to merge my changes with your most recent git version.<o:p></o:p></span></p></div></body></html>