2015-07-24 14:13 GMT+02:00 Alexander Aring <alex.aring@xxxxxxxxx>: > On Fri, Jul 24, 2015 at 02:03:09PM +0200, Baptiste Clenet wrote: >> 2015-07-24 12:18 GMT+02:00 Alexander Aring <alex.aring@xxxxxxxxx>: >> > On Fri, Jul 24, 2015 at 11:56:08AM +0200, Baptiste Clenet wrote: >> >> 2015-07-24 11:48 GMT+02:00 Alexander Aring <alex.aring@xxxxxxxxx>: >> >> > On Fri, Jul 24, 2015 at 11:02:30AM +0200, Baptiste Clenet wrote: >> >> >> 2015-07-24 10:47 GMT+02:00 Baptiste Clenet <bapclenet@xxxxxxxxx>: >> >> >> > 2015-07-24 10:31 GMT+02:00 Alexander Aring <alex.aring@xxxxxxxxx>: >> >> >> >> Hi, >> >> >> >> >> >> >> >> On Fri, Jul 24, 2015 at 09:56:49AM +0200, Baptiste Clenet wrote: >> >> >> >>> Hi, >> >> >> >>> >> >> >> >>> What is SAM value? I got "ieee802154 phy0 wpan0: SAM value 0x3 not >> >> >> >>> supported" when I receive a ping from another board. >> >> >> >>> >> >> >> >> >> >> >> >> I think you hit [0]. You got that because we received some 6LoWPAN frame >> >> >> >> with context based address compression (the source address). See also [1]. >> >> >> > Yes for [0] >> >> >> > >> >> >> >> >> >> >> >> Your options are: >> >> >> >> >> >> >> >> - That the other board use stateless (means SAC = 0, see [1]) address >> >> >> >> compression. >> >> >> > How may I check? >> >> >> > They use both the same settings, they are based on the same source code. >> >> >> SAC bit is set. >> >> > >> >> > Yes SAC bit means context based address compression and we don't support >> >> > it. We should support it, that's what rfc6282 said. But we don't have >> >> > support for that now. :-) >> >> > >> >> > What do you mean with "they are based on the same source code"? It's a >> >> > linux<->linux communication? >> >> Yes it is linux to linux transmission. >> >> Yeah I understand for the support :-) >> >> The question is now why my linux use context based address compression >> >> if it shouldn't? Where is it (SAC) set when transmitting a message? >> >> >> > >> > We don't set it. Which kernel do you use? >> Linux 4.1.0 (yeah I should use bluetooth-next kernel) >> I see that the only way it is set is when >> 'source address is unspecified, setting SAC' >> > > yes, apologize it wasn't correct. But the SAM value was 0x3 in your case > and this shouldn't be. > > The SAC = 1 and SAM = 0 is a very simple case [0]. It's simple do > nothing. > >> root@OpenWrt:/# ifconfig >> lowpan0 Link encap:UNSPEC HWaddr >> 07-7B-21-44-65-D9-6F-AC-00-00-00-00-00-00-00-00 >> inet6 addr: fe80::57b:2144:65d9:6fac/64 Scope:Link >> UP BROADCAST RUNNING MULTICAST MTU:1280 Metric:1 >> RX packets:0 errors:0 dropped:0 overruns:0 frame:0 >> TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 >> collisions:0 txqueuelen:0 >> RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) >> >> wpan0 Link encap:UNSPEC HWaddr >> 07-7B-21-44-65-D9-6F-AC-00-00-00-00-00-00-00-00 >> UP BROADCAST RUNNING NOARP MTU:127 Metric:1 >> RX packets:20 errors:0 dropped:0 overruns:0 frame:0 >> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0 >> collisions:0 txqueuelen:300 >> RX bytes:1001 (1001.0 B) TX bytes:568 (568.0 B) >> >> (There is some printk for irq as well) >> root@OpenWrt:/#ip link set lowpan0 up >> root@OpenWrt:/# [ 66.248286] IPv6 header dump: >> [ 66.248286] version = 6 >> [ 66.248286] length = 36 >> [ 66.248286] nexthdr = 0x00 >> [ 66.248286] hop_lim = 1 >> [ 66.248286] dest = ff02::16 >> [ 66.281193] source address is unspecified, setting SAC >> // ?? > > Yes this is simple case at [0]. But then SAM should be 0 not 3. And in > some previous mail it was set 3 in your case. Yes if SAC = 1, SAM should be 0 I agree. Is that somehow possible that I send ihpc of 7b39 (taken at the end of lowpan_header_compress) and I receive and iphc of 7bf9 (taken at the begginning of lowpan_header_decompress) every time?? > > We set the SAC bit once at [1] only, but then SAM should be 0. > > - Alex > > [0] http://lxr.free-electrons.com/source/net/6lowpan/iphc.c#L148 -- Baptiste -- 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
