Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[johnzeng]

Hello Dear Sir :

Whether Batman-adv need suitable wifi network card (support interface
modes ( mesh point ) ) .

there are two wifi network card , and i thought Rt2070 will support
Batman-adv .

Because Rt2070 will support interface modes ( mesh point ) , and
RTL8188CUS can't support interface modes based mesh point .


this is some info via iw list , whether it will be correct understanding ?



Bus 001 Device 005: ID 148f:2070 Ralink Technology, Corp. RT2070
Wireless Adapter

Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* WDS
* monitor
* mesh point



8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter

Supported interface modes:
* IBSS
* managed
* AP
* monitor
* P2P-client
* P2P-GO

Re: [B.A.T.M.A.N.] Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Sven Eckelmann]

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On Dienstag, 25. Oktober 2016 17:25:50 CEST johnzeng wrote:
> 
> Hello Dear Sir :
> 
> Whether Batman-adv need suitable wifi network card (support interface
> modes ( mesh point ) ) .

"mesh point" is for 802.11s. You can use 802.11s (mesh point) interfaces
for batman-adv when you set mesh_fwding to 0. But most people use IBSS
(adhoc) at the moment for batman-adv. It doesn't really care that much
about the underlying interface. It just has to be ethernet compatible
and support some basic features like broadcast.

So you could even run infrastructure mode (AP+Sta) with batman-adv. But
it doesn't make a lot of sense in most situations :)

The B.A.T.M.A.N. V algorithm implementation has some extra requirements.
It must be able to get the expected throughput towards a different device
from cfg80211. You can check if the driver supports this by checking
`iw dev wlan0 station dump` and searching for "expected throughput:".
The Mpbs value should represent the reality (and not be complete bogus).

The biggest problems here are driver/hw bugs. Even the ath9k hardware
(which works quite well) has its fair share of problems.

> there are two wifi network card , and i thought Rt2070 will support
> Batman-adv .
> 
> Because Rt2070 will support interface modes ( mesh point ) , and
> RTL8188CUS can't support interface modes based mesh point .

Both advertise support for IBSS. So you can (in theory) use adhoc on
both devices and run batman-adv on top of these adhoc interfaces. But
you may end up with driver problems (at least I already had problems
with Realtek and Ralink hardware). Maybe someone else here already
tested these two chips and tell us more about them.

Kind regards,
	Sven

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Re: Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[johnzeng]

Hello Sven:

Thanks you for your advisement , and i will start via two Rt2070 at 
first , but i will purchase suitable wifi network card or wifi module 
recently ,

Whether Atheros (AR54xx、AR91xx、AR92xx、AR93xx及AR95xx) will be 
suitable for batman-adv ?

their driver is ath9k .


Have a good day with you

Best Regards

Tiger

于 2016年10月25日 17:45, Sven Eckelmann 写道:
> On Dienstag, 25. Oktober 2016 17:25:50 CEST johnzeng wrote:
>> Hello Dear Sir :
>>
>> Whether Batman-adv need suitable wifi network card (support interface
>> modes ( mesh point ) ) .
> "mesh point" is for 802.11s. You can use 802.11s (mesh point) interfaces
> for batman-adv when you set mesh_fwding to 0. But most people use IBSS
> (adhoc) at the moment for batman-adv. It doesn't really care that much
> about the underlying interface. It just has to be ethernet compatible
> and support some basic features like broadcast.
>
> So you could even run infrastructure mode (AP+Sta) with batman-adv. But
> it doesn't make a lot of sense in most situations :)
>
> The B.A.T.M.A.N. V algorithm implementation has some extra requirements.
> It must be able to get the expected throughput towards a different device
> from cfg80211. You can check if the driver supports this by checking
> `iw dev wlan0 station dump` and searching for "expected throughput:".
> The Mpbs value should represent the reality (and not be complete bogus).
>
> The biggest problems here are driver/hw bugs. Even the ath9k hardware
> (which works quite well) has its fair share of problems.
>
>> there are two wifi network card , and i thought Rt2070 will support
>> Batman-adv .
>>
>> Because Rt2070 will support interface modes ( mesh point ) , and
>> RTL8188CUS can't support interface modes based mesh point .
> Both advertise support for IBSS. So you can (in theory) use adhoc on
> both devices and run batman-adv on top of these adhoc interfaces. But
> you may end up with driver problems (at least I already had problems
> with Realtek and Ralink hardware). Maybe someone else here already
> tested these two chips and tell us more about them.
>
> Kind regards,
> 	Sven

Re: [B.A.T.M.A.N.] Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Sven Eckelmann]

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On Mittwoch, 26. Oktober 2016 08:48:36 CEST johnzeng wrote:
> 
> Hello Dear SIr :
> 
>                           I am testing between RTL8188CUS 802.11n WLAN 
> Adapter and Rt2070 now ,
> 
> 
> 
>                           When i ping hostB from hostA ,
> 
>                           hostA show ping info  , ( From 10.10.130.66 
> icmp_seq=211 Destination Host Unreachable )
> 
>                          and i catch some info via tcpdump at hostB.   i 
> guess it was caused by not suitable RTL8188CUS or driver .

Please check if the underlying link works. Check `iw dev wlan0 station dump` 
and add an ip in a separate ip subnet to the wlan0 and try to ping each other 
via this ip. Also check `batctl o` to find out if the batman-adv nodes can see 
each other.

Kind regards,
	Sven

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Re: [B.A.T.M.A.N.] Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Sven Eckelmann]

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On Mittwoch, 26. Oktober 2016 07:19:59 CEST johnzeng wrote:
[...]
> Whether Atheros (AR54xx、AR91xx、AR92xx、AR93xx及AR95xx) will be 
> suitable for batman-adv ?
> 
> their driver is ath9k .
[...]

All should work in their PCI(e) version and I think I've used all
of them in the past - not sure about AR54xx (which were early
draft-n devices). The first three are rather old and they would
not be my first choice.

Kind regards,
	Sven

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Re: Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[johnzeng]

Hello Sven:






HostB wlan0 : mac addr : ether 00:1d:43:10:15:44

HostA wlan0 : mac addr: ether c8:3a:35:c9:ce:71




i run the command at Host A ( Rt2070 ) at ( ping HostA from HostB)
iw dev wlan0 station dump:
Station 00:1d:43:10:15:44 (on wlan0)
inactive time: 140 ms
rx bytes: 4977553
rx packets: 126014
tx bytes: 0
tx packets: 0
tx retries: 0
tx failed: 0
rx drop misc: 0
signal: -39 dBm
signal avg: -39 dBm
tx bitrate: 1.0 MBit/s
rx bitrate: 1.0 MBit/s
authorized: yes
authenticated: yes
associated: yes
preamble: long
WMM/WME: no
MFP: no
TDLS peer: no
DTIM period: 0
beacon interval:100
connected time: 10084 seconds

[root@alarmpi ~]# tcpdump -i bat0

07:01:40.635517 ARP, Reply 0.0.0.0 is-at 43:05:43:05:00:00 (oui 
Unknown), length 28
07:01:50.655521 ARP, Reply 0.0.0.0 is-at 43:05:43:05:00:00 (oui 
Unknown), length 28

[root@alarmpi ~]# tcpdump -i wlan0
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on wlan0, link-type EN10MB (Ethernet), capture size 262144 bytes
07:02:35.815528 c8:3a:35:c9:ce:71 (oui Unknown) > Broadcast, ethertype 
Unknown (0x4305), length 66:
0x0000: 000f 3202 d7e6 278c c83a 35c9 ce71 c83a ..2...'..:5..q.:
0x0010: 35c9 ce71 00ff 001c 0401 000c 0104 0001 5..q............
0x0020: 48b5 3b30 0000 0000 0601 0004 0000 0000 H.;0............
0x0030: 0201 0000


and i ping ip address belong to hostB (wlan0 )from HostA and it will be 
fine .

batctl o No batman nodes in range

-----------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------

and i run same command at Host B ( RTL8188CUS ) at ( ping HostB from HostA)

iw dev wlan0 station dump:

" is blank "

[root@alarmpi ~]# tcpdump -i bat0
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on bat0, link-type EN10MB (Ethernet), capture size 262144 bytes
06:55:51.505401 ARP, Request who-has bogon tell bogon, length 28
06:55:51.506177 ARP, Reply bogon is-at a6:b8:8a:11:be:a2 (oui Unknown), 
length 28

tcpdump -i wlan0

06:57:11.425351 c8:3a:35:c9:ce:71 (oui Unknown) > Broadcast, ethertype 
Unknown (0x4305), length 66:
0x0000: 000f 3202 d7e6 2649 c83a 35c9 ce71 c83a ..2...&I.:5..q.:
0x0010: 35c9 ce71 00ff 001c 0401 000c 0104 0001 5..q............
0x0020: 48b5 3b30 0000 0000 0601 0004 0000 0000 H.;0............
0x0030: 0201 0000 ....
06:57:11.534759 00:1d:43:10:15:44 (oui Unknown) > Broadcast, ethertype 
Unknown (0x4305), length 66:
0x0000: 000f 3105 d7e6 2649 c83a 35c9 ce71 c83a ..1...&I.:5..q.:
0x0010: 35c9 ce71 0000 001c 0401 000c 0104 0001 5..q............
0x0020: 48b5 3b30 0000 0000 0601 0004 0000 0000 H.;0............
0x0030: 0201 0000


and i ping ip address belong to hostA wlan0 from HostB and it will be fine .

batctl o No batman nodes in range


------------------------------------------------------------------------------------------------------------

And i thought Rt2070 support Broadcast and RTL8188CUS don't support 
Broadcast or send ...

because when i ping ip (RTL8188CUS) from Rt2070 , and i can see ping 
packet via (tcpdump -i bat0 ) and i can see Rt2070 mac addr via (tcpdump 
-i wlan0 ) at HOSTB,

but i ping ip (Rt2070) from RTL8188CUS and i can't see any ping packet 
from RTL8188CUS and i can't see RTL8188CUS mac via (tcpdump -i wlan0 ) 
at HOSTA


Whether it will be master reason ?


Thanks
...










于 2016年10月26日 14:07, Sven Eckelmann 写道:
> iw dev wlan0 station dump

Re: [B.A.T.M.A.N.] Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Sven Eckelmann]

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On Mittwoch, 26. Oktober 2016 15:19:02 CEST johnzeng wrote:
[...] 
> HostB wlan0 : mac addr : ether 00:1d:43:10:15:44
> 
> HostA wlan0 : mac addr: ether c8:3a:35:c9:ce:71
[...]
> i run the command at Host A ( Rt2070 ) at ( ping HostA from HostB)
> iw dev wlan0 station dump:
> Station 00:1d:43:10:15:44 (on wlan0)
[...]

Here we see that host A noticed that there is a different device and
"connected" to it (actually, it just added it as remote station to its
internal list).

This is a good sign - at least when both devices have each other in
their respective station lists (*spoiler* they don't).

> 
> [root@alarmpi ~]# tcpdump -i bat0
> 
> 07:01:40.635517 ARP, Reply 0.0.0.0 is-at 43:05:43:05:00:00 (oui 
> Unknown), length 28
> 07:01:50.655521 ARP, Reply 0.0.0.0 is-at 43:05:43:05:00:00 (oui 
> Unknown), length 28
> 
> [root@alarmpi ~]# tcpdump -i wlan0
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on wlan0, link-type EN10MB (Ethernet), capture size 262144 bytes
> 07:02:35.815528 c8:3a:35:c9:ce:71 (oui Unknown) > Broadcast, ethertype 
> Unknown (0x4305), length 66:
[...]

Here we see an OGM that is transmitted from this device. So for some reason
we don't see the an incoming OGM from host B. Either host B is not really
transmitting it, host A is not receiving it or you just didn't capture long
enough.

[...]
> and i run same command at Host B ( RTL8188CUS ) at ( ping HostB from HostA)
> 
> iw dev wlan0 station dump:
> 
> " is blank "

This means that RTL8188CUS didn't detect a remote IBSS device. This is odd and
at first glance looks to me like a bug in the RTL8188CUS driver. But I would
recommend to get a third (known to work) device and check to which of the
orignal two devices it can connect and which of the other two devices can
connect to it.

You could even use the third device to capture raw wifi frames on a monitor
interface and check if both devices submit these OGMs and if both devices
are beaconing (and reply to probe requests).

But this is basically the main problem here.
The rest of the reply is just to explain some additional things.
---------------------------------------------------------------

[...]
> tcpdump -i wlan0
> 
> 06:57:11.425351 c8:3a:35:c9:ce:71 (oui Unknown) > Broadcast, ethertype 
[...]
> 06:57:11.534759 00:1d:43:10:15:44 (oui Unknown) > Broadcast, ethertype 
[...]

This part shows an OGM from host A and host B. So it can receive OGMs from
other stations and batman-adv is at least trying to send some data. It is
unknown here if the host B is not really sending it or if host A is not
really receiving it.

[...]
> And i thought Rt2070 support Broadcast and RTL8188CUS don't support 
> Broadcast or send ...
> 
> because when i ping ip (RTL8188CUS) from Rt2070 , and i can see ping 
> packet via (tcpdump -i bat0 ) and i can see Rt2070 mac addr via (tcpdump 
> -i wlan0 ) at HOSTB,
> 
> but i ping ip (Rt2070) from RTL8188CUS and i can't see any ping packet 
> from RTL8188CUS and i can't see RTL8188CUS mac via (tcpdump -i wlan0 ) 
> at HOSTA

Both should have working broadcast to get the ARP stuff working for the ping.
But of course this only a good test when each ping tests are done with clean
ARP tables (Linux is sniffing packets to fill its own ARP table without always
sending ARP request). There is a test which you could have done even without
the `iw dev wlan0 station dump` info from above.

This part now is without batman-adv (because the text from you is quite unclear):
--------------------------------------------------------------------------------

But it could be that the ARP table on RTL8188CUS (Host B) was filled by the
ARP request from Host A. And this was to only reason why the ping back from
host B to host A worked.  You can test that by making sure that the ARP table
is clean on both hosts and then start pinging from B to A. Also make some
captures with tcpdump on both hosts that you later can analyze with wireshark.
After your test (when it worked) make sure that the arp table on both hosts
contain entries for each other. And than analyze the dumps for ARP packets in
wireshark to make sure that host B really submitted and request and host A
replied to it.

Kind regards,
	Sven

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Re: Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[johnzeng]

Dear Sven :

                     Thanks , and i will try to purchase suitable wifi 
hardware ,

                      Because i use raspberry 
<http://www.baidu.com/link?url=s_ofbUc1ZEO-1ohz5A3WnLdqY4CNZ948d7JxBMkwZtW_fjTcOKUwMjkloBUHVW475SCTMxAci7HoEvHeH80Fuz9lC1X4W6Hw4BvwQaUIDzq> 
pi  , i have to use wifi card based usb .

                      whether you can advise a set of usb wifi card 
based Atheros ( driver ath9k) ?



                       Best Regards

                       Tiger



> On Mittwoch, 26. Oktober 2016 15:19:02 CEST johnzeng wrote:
> [...]
>> HostB wlan0 : mac addr : ether 00:1d:43:10:15:44
>>
>> HostA wlan0 : mac addr: ether c8:3a:35:c9:ce:71
> [...]
>> i run the command at Host A ( Rt2070 ) at ( ping HostA from HostB)
>> iw dev wlan0 station dump:
>> Station 00:1d:43:10:15:44 (on wlan0)
> [...]
>
> Here we see that host A noticed that there is a different device and
> "connected" to it (actually, it just added it as remote station to its
> internal list).
>
> This is a good sign - at least when both devices have each other in
> their respective station lists (*spoiler* they don't).
>
>> [root@alarmpi ~]# tcpdump -i bat0
>>
>> 07:01:40.635517 ARP, Reply 0.0.0.0 is-at 43:05:43:05:00:00 (oui
>> Unknown), length 28
>> 07:01:50.655521 ARP, Reply 0.0.0.0 is-at 43:05:43:05:00:00 (oui
>> Unknown), length 28
>>
>> [root@alarmpi ~]# tcpdump -i wlan0
>> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
>> listening on wlan0, link-type EN10MB (Ethernet), capture size 262144 bytes
>> 07:02:35.815528 c8:3a:35:c9:ce:71 (oui Unknown) > Broadcast, ethertype
>> Unknown (0x4305), length 66:
> [...]
>
> Here we see an OGM that is transmitted from this device. So for some reason
> we don't see the an incoming OGM from host B. Either host B is not really
> transmitting it, host A is not receiving it or you just didn't capture long
> enough.
>
> [...]
>> and i run same command at Host B ( RTL8188CUS ) at ( ping HostB from HostA)
>>
>> iw dev wlan0 station dump:
>>
>> " is blank"
> This means that RTL8188CUS didn't detect a remote IBSS device. This is odd and
> at first glance looks to me like a bug in the RTL8188CUS driver. But I would
> recommend to get a third (known to work) device and check to which of the
> orignal two devices it can connect and which of the other two devices can
> connect to it.
>
> You could even use the third device to capture raw wifi frames on a monitor
> interface and check if both devices submit these OGMs and if both devices
> are beaconing (and reply to probe requests).
>
> But this is basically the main problem here.
> The rest of the reply is just to explain some additional things.
> ---------------------------------------------------------------
>
> [...]
>> tcpdump -i wlan0
>>
>> 06:57:11.425351 c8:3a:35:c9:ce:71 (oui Unknown) > Broadcast, ethertype
> [...]
>> 06:57:11.534759 00:1d:43:10:15:44 (oui Unknown) > Broadcast, ethertype
> [...]
>
> This part shows an OGM from host A and host B. So it can receive OGMs from
> other stations and batman-adv is at least trying to send some data. It is
> unknown here if the host B is not really sending it or if host A is not
> really receiving it.
>
> [...]
>> And i thought Rt2070 support Broadcast and RTL8188CUS don't support
>> Broadcast or send ...
>>
>> because when i ping ip (RTL8188CUS) from Rt2070 , and i can see ping
>> packet via (tcpdump -i bat0 ) and i can see Rt2070 mac addr via (tcpdump
>> -i wlan0 ) at HOSTB,
>>
>> but i ping ip (Rt2070) from RTL8188CUS and i can't see any ping packet
>> from RTL8188CUS and i can't see RTL8188CUS mac via (tcpdump -i wlan0 )
>> at HOSTA
> Both should have working broadcast to get the ARP stuff working for the ping.
> But of course this only a good test when each ping tests are done with clean
> ARP tables (Linux is sniffing packets to fill its own ARP table without always
> sending ARP request). There is a test which you could have done even without
> the `iw dev wlan0 station dump` info from above.
>
> This part now is without batman-adv (because the text from you is quite unclear):
> --------------------------------------------------------------------------------
>
> But it could be that the ARP table on RTL8188CUS (Host B) was filled by the
> ARP request from Host A. And this was to only reason why the ping back from
> host B to host A worked.  You can test that by making sure that the ARP table
> is clean on both hosts and then start pinging from B to A. Also make some
> captures with tcpdump on both hosts that you later can analyze with wireshark.
> After your test (when it worked) make sure that the arp table on both hosts
> contain entries for each other. And than analyze the dumps for ARP packets in
> wireshark to make sure that host B really submitted and request and host A
> replied to it.
>
> Kind regards,
> 	Sven

Re: [B.A.T.M.A.N.] Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Sven Eckelmann]

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On Mittwoch, 26. Oktober 2016 20:52:13 CEST johnzeng wrote:
[...]
> Thanks , and i will try to purchase suitable wifi hardware ,
> 
> Because i use raspberry [...]pi  , i have to use wifi card based usb .
> 
> whether you can advise a set of usb wifi card  based Atheros ( driver ath9k) ?

Sorry, I have zero experience with the USB hardware (ath9k_htc/carl9170). I
think Martin was using them some time ago. Or maybe someone else on the ml
has more information about them.

But these devices use a firmware running on the device. I know that there
were weird problems hunting the carl9170 hardware/firmware [1]. Th
ath9k_htc looks a little better but the TODO list for the firmware is also
quite large and there also some odd limitations mentioned on the driver
page [2].

Kind regards,
	Sven

[1] https://wireless.wiki.kernel.org/en/users/drivers/carl9170
[2] https://wireless.wiki.kernel.org/en/users/drivers/ath9k_htc


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Re: Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[johnzeng]

Hello Dear Sven:

Thanks you really ,


i am searching /lib/modules/4.4.26-1-ARCH/kernel/drivers/net/wireless/ath/

Maybe there are suitable driver and hardware .


Have a good day


Best Regards

Tiger


于 2016年10月26日 21:05, Sven Eckelmann 写道:
> ices use a firmware running on the device. I know that there
> were weird problems hunting the carl9170 hardware/firmware [1]. Th
> ath9k_htc looks a little better but the TODO list for the firmware is also
> quite large and there also some odd limit

Re: Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Martin Hundebøll]

On October 26, 2016 3:05:47 PM GMT+02:00, Sven Eckelmann <sven@narfation.org> wrote:
>On Mittwoch, 26. Oktober 2016 20:52:13 CEST johnzeng wrote:
>[...]
>> Thanks , and i will try to purchase suitable wifi hardware ,
>> 
>> Because i use raspberry [...]pi  , i have to use wifi card based usb
>.
>> 
>> whether you can advise a set of usb wifi card  based Atheros ( driver
>ath9k) ?
>
>Sorry, I have zero experience with the USB hardware
>(ath9k_htc/carl9170). I
>think Martin was using them some time ago. Or maybe someone else on the
>ml
>has more information about them.

Yeah, I used them for some lab tests a few years back. The ath9k_htc works quite well with the exception that the chip/firmware/driver only supports 7 or 8 nodes within range due to limited resources on the chip.

// Martin

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: [B.A.T.M.A.N.] Whether Batman-adv need suitable wifi network card (support interface modes ( mesh point ) ) .

[Simon Wunderlich]

[-- Attachment #1: Type: text/plain, Size: 711 bytes --]

On Wednesday, October 26, 2016 2:52:39 PM CEST johnzeng via B.A.T.M.A.N wrote:
> Dear Sven :
> 
>                      Thanks , and i will try to purchase suitable wifi 
> hardware ,
> 
>                       Because i use raspberry 
> <http://www.baidu.com/link?url=s_ofbUc1ZEO-1ohz5A3WnLdqY4CNZ948d7JxBMkwZtW_f
> jTcOKUwMjkloBUHVW475SCTMxAci7HoEvHeH80Fuz9lC1X4W6Hw4BvwQaUIDzq>  pi  , i
> have to use wifi card based usb .
> 
>                       whether you can advise a set of usb wifi card 
> based Atheros ( driver ath9k) ?

After looking at different USB chips, I would also recommend looking into 
ath9k_htc first. Even if it has limitations, other chips are doing much worse 
...

Cheers,
     Simon

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