Bow-Nan, It is the responsibility of the EMANE transport layer to determine the NEM destination Id to use for traffic routed through the emulator. The transport acts as a boundary understanding enough of the input protocol to determine the appropriate NEM destination Id.
Both the raw transport and the virtual transport operate on ethernet frames. For a given input frame, these transports map the destination MAC address to the appropriate NEM Id. When this is not possible the NEM broadcast address is used. Since all over-the-air frames in EMANE are delivered to all NEMs for physical layer processing, this will have no impact on the emulation. The MAC layers (provided they are of the same waveform) will process the messages as if they were broadcast and pass them back to the corresponding transport which will then deliver the packets to the kernel for processing. In this case, if it turns out that a packet was unicast and not broadcast but was not for the receiving node, the kernel will drop it. As far as DSCP is concerned, a 0 value is used for non-IP packets. A DSCP value of 0 would have no impact on the RF Pipe model but could have an impact on the IEEE80211abg Model if WMM (Wireless Multi Media) is enabled and the DSCP values are being set by the application generating the traffic. -- Steven Galgano Adjacent Link LLC On 04/11/2013 06:04 PM, Cheng, Bow-Nan - 0665 - MITLL wrote: > Hello, > > We're implementing some IP Header Compression protocols. To do so, we > modify the ETHERTYPE to be something custom. Looking through some of the > EMANE 0.8.1 Code, it seems that a non-IP/ARP ETHERTYPE gets accepted, > but I'm wondering what the repercussions are of not having an IP header > in EMANE? For example, some models search for DSCP values in the header, > IPv6 ND packets would not have parsable headers since the IPv6 header > would be compressed, etc. I'm seeing a lot of multicast traffic being > pushed down and upstream in EMANE by doing an unknown Ethertype and > unknown network layer header and was wondering if its requiring > something special from the IP header I'm not giving. Using RF Pipe.. > > Thanks! > > -Bow-Nan > > -- > Bow-Nan Cheng, Ph.D. > MIT Lincoln Laboratory > Airborne Networks Group > 244 Wood St Lexington MA 02420 > 781-981-4997 > > > _______________________________________________ > emane-users mailing list > [email protected] > http://pf.itd.nrl.navy.mil/mailman/listinfo/emane-users > _______________________________________________ emane-users mailing list [email protected] http://pf.itd.nrl.navy.mil/mailman/listinfo/emane-users
