"Johnny" == Johnny Billquist <bqt at softjar.se> writes: gerry> We still do not know how these UDP related problems would/will gerry> impact other protocols like LAT, LAD/LAST and MOP because we gerry> haven't experimented so much as with pure DECnet. Any gerry> contribution and suggestions on how to force reduced frame gerry> size for those protocols would be much appreciated. :-) I can't think of any. The general rule at DEC was that some basic level of design competence was assumed. Getting the Ethernet frame size right was certainly part of the basic IQ test. The only solution I can think of is to reduce the MTU of your local Ethernet on the machine doing the UDP encapsulation. That would force the packets to be fragmented at origination time, which means your defective routers will see small-enough packets. Johnny> If I suspect right, that won't solve it. I haven't any Johnny> direct experience with these kind of problems, but the few Johnny> cases that I'm semi-aware of are actually of Johnny> bridges/gateways/routers that can't handled IP Johnny> fragments. Forcing a fragment even earlier won't help. Oh. I thought the issue was that those "routers" couldn't do fragmentation right. If the problem is that they look at the header to see if it's fragmented -- which is something they should not care about -- and then proceed to get confused, then indeed they are beyond all hope and the only solution is to scrap them and get real routers. paul