Hello. On 15/03/16 06:19, Remi Philippe wrote:
On Tue, Mar 15, 2016 at 3:11 AM, Michael Richardson <mcr@xxxxxxxxxxxx> wrote:Stefan Schmidt <stefan@xxxxxxxxxxxxxxx> wrote: > 2) If the 802.15.4g node uses a SUN PHY with a 2047 byte MTU we can run into > trouble with normal nodes only able to handle 127. So far there is nothing > specified to handle this case. Michael is proposing to use 6lo ND for this > and record the MTU value for this neighbour in the l2 nd cache. Something > that would certainly work but would need specing and implementing. I see this > as a mid term goal we want to have. Anyone going to work on this? It's not even clear to me that ND can do this. I still propose that we want to have a space in the l2 or l3 ND cache for this info. It could well go in the L3 cache because it is really a statement about how the 6lowpan layer should fragment. > 3) Until 2) is done I would suggest we add a config option "802.15.4g with > SUN PHY" which will change the hardcoded MTU from 127 to 2047 and will thus > only work for a 15.g with SUN PHY only network. No interop as we have no way > of knowing. The option would be disabled by default and the help text needs > to mention the drawbacks. Once we have 2) in place we can remove this. Couldn't we use "ifconfig blah0 mtu 2047"?Maybe we should do both, have a flag to specify the PHY type as the PHY header is slightly different in15.4g MR-FSK to support for mode switch, data whitening... it needs to support 2 octets header (page 52 of the 802.15.4g-2012 spec) it can also lock the max MTU supported for the media. And allow to change the MTU from command line.
Did you move on with this? If you ahve any patches let us know. We are happily going to review them.
regards Stefan Schmidt -- To unsubscribe from this list: send the line "unsubscribe linux-wpan" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
