Hi all,
I am evaluating the performance of some USB sticks, some of them have
a Ralink chipset, yet I don't get thoughputs anything near the
300Mbit that all of the sticks advertise and I would like to ask this
forum if anyone has any hints about why.
I will describe my system and my test procedure.
I basically build an access point using HostAPD (0.7.3) using DHCP and
I transfer a file using Samba for the shared folders functionality,
from a Linux 3.4.7 system into a Windows system. If the trasfer is
done via our Gigabit network, I get transfer rates of 100 Mbit (which
is the maximum that the Linux box can deliver as it has a 100 Mbit
adapter). When transfering the file via Wireless, and after tweaking
the HostAPD conf file a bit I could get a maximum of 3.3 MBps (~ 27
Mbit) which is 10% from the advertised speed. My Windows PC has an
Atheros AR9287 which is 2T2R as well and thus is be able to handle the
300 Mbit. Both devices are 1m apart and I chose channel 6 which is the
least polluted one in my environment.
I am mainly interested in the Access Point transfers, yet I have
tested the Ad-Hoc connection as well (yet only 802.11.g 54Mbit) and
with that I get even slower transfer rates.
USB Chipset
Ralink 3072
Linux box:
Kernel 3.4.7 Vanilla
HostAPD conf:
#===============================
interface=wlan2
driver=nl80211
ssid=LLS0610007xx
channel=6
hw_mode=g
max_num_sta=5
ctrl_interface=/var/run/hostapd
ignore_broadcast_ssid=0
rts_threshold=2347
fragm_threshold=2346
macaddr_acl=0
logger_syslog=-1
logger_syslog_level=0
logger_stdout=-1
logger_stdout_level=0
dump_file=/tmp/hostapd.dump
ieee80211n=1
ht_capab=[HT40-][SHORT-GI-20][SHORT-GI-40][TX-STBC][RX-STBC12]
auth_algs=1
wpa=2
wpa_key_mgmt=WPA-PSK
wpa_pairwise=CCMP
wpa_group_rekey=86400
wpa_gmk_rekey=86400
wpa_passphrase=0123456789
#===============================
iw list:
Wiphy phy4
Band 1:
Capabilities: 0x2f2
HT20/HT40
Static SM Power Save
RX Greenfield
RX HT20 SGI
RX HT40 SGI
TX STBC
RX STBC 2-streams
Max AMSDU length: 3839 bytes
No DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 2 usec (0x04)
HT RX MCS rate indexes supported: 0-15, 32
TX unequal modulation not supported
HT TX Max spatial streams: 2
HT TX MCS rate indexes supported may differ
Frequencies:
* 2412 MHz [1] (0.0 dBm)
* 2417 MHz [2] (0.0 dBm)
* 2422 MHz [3] (0.0 dBm)
* 2427 MHz [4] (0.0 dBm)
* 2432 MHz [5] (0.0 dBm)
* 2437 MHz [6] (0.0 dBm)
* 2442 MHz [7] (0.0 dBm)
* 2447 MHz [8] (0.0 dBm)
* 2452 MHz [9] (0.0 dBm)
* 2457 MHz [10] (0.0 dBm)
* 2462 MHz [11] (0.0 dBm)
* 2467 MHz [12] (0.0 dBm) (passive scanning, no IBSS)
* 2472 MHz [13] (0.0 dBm) (passive scanning, no IBSS)
* 2484 MHz [14] (0.0 dBm) (passive scanning, no IBSS)
Bitrates (non-HT):
* 1.0 Mbps
* 2.0 Mbps (short preamble supported)
* 5.5 Mbps (short preamble supported)
* 11.0 Mbps (short preamble supported)
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
max # scan SSIDs: 4
max scan IEs length: 2257 bytes
Coverage class: 0 (up to 0m)
Supported Ciphers:
* WEP40 (00-0f-ac:1)
* WEP104 (00-0f-ac:5)
* TKIP (00-0f-ac:2)
* CCMP (00-0f-ac:4)
Available Antennas: TX 0 RX 0
Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* WDS
* monitor
software interface modes (can always be added):
* AP/VLAN
* monitor
interface combinations are not supported
Supported commands:
* new_interface
* set_interface
* new_key
* new_beacon
* new_station
* set_bss
* authenticate
* associate
* deauthenticate
* disassociate
* join_ibss
* remain_on_channel
* set_tx_bitrate_mask
* action
* frame_wait_cancel
* set_wiphy_netns
* set_channel
* set_wds_peer
* Unknown command (84)
* Unknown command (87)
* Unknown command (85)
* connect
* disconnect
Supported TX frame types:
* IBSS: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80
0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* managed: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80
0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP/VLAN: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* mesh point: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-client: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-GO: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
Supported RX frame types:
* IBSS: 0xd0
* managed: 0x40 0xd0
* AP: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* AP/VLAN: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* mesh point: 0xb0 0xc0 0xd0
* P2P-client: 0x40 0xd0
* P2P-GO: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
HT Capability overrides:
* MCS: ff ff ff ff ff ff ff ff ff ff
* maximum A-MSDU length
* supported channel width
* short GI for 40 MHz
* max A-MPDU length exponent
* min MPDU start spacing
Device supports TX status socket option.
Device supports HT-IBSS.
Does anyone have a clue?
Regards,
--
________________________________
Juan Carlos Garza
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