On 2011-07-17 19.55, hvlems at zonnet.nl wrote: If there is no router present (on ethernet) then an endnode will just try and send the datagram. It knows the destination decnet address and thus can compute the target mac address. Right. Thinking a little more I realize that it will do this. This would not be very useful in HECnet, since we have several areas, and not everything is connected to the bridge. So routers are definitely needed, and thus you need atleast one L2 router in your area in order to talk to machines in other areas which you do not have a direct connection to. Or else you'll isolate yourself to only talk to directly connected machines. Johnny ------Origineel bericht------ Van: Johnny Billquist Afzender: owner-hecnet at Update.UU.SE Aan: hecnet at Update.UU.SE Beantwoorden: hecnet at Update.UU.SE Onderwerp: Re: [HECnet] DECnet et al Verzonden: 17 juli 2011 19:49 On 2011-07-17 19.45, Bob Armstrong wrote: And so those packets will be tossed. Tossed by who? The bridge program? No. By the endnode itself. It have no idea where to send it. For ethernet, DECnet supposedly already knows the MAC address where to send every packet. Where would it send a packet that isn't to the local ethernet segment? It needs to send it to a router, which will forward it. But since there is no router, there is nothing it can do with it. DECnet data traffic is not broadcast... Just as information - from MIM, the area furthest away is are 59, which is three hops distance. So it packets needs to pass through two intermediate level 2 routers to get to the right area. Johnny Verzonden vanaf mijn draadloze BlackBerry -toestel