View Full Version : [ubuntu] Wireless packet loss goes to 100% after ~20 requests

September 18th, 2011, 06:14 PM
I have Comcast cable internet and I'm using a Motorola SB6120 modem connected to a Linksys WRT54GL router. My desktop is connected to the router via Ethernet and internet always works great.

However, my laptop (running Ubuntu 10.10) connects via wireless, and for each web request, packet loss seems to go up. After about 20 requests, the packet loss reaches 100%, and I can't even ping the gateway. The laptop reports that it is still connected to wireless with a strong signal.

Disconnecting and reconnecting to the access point doesn't help, as well as logging out and back in. However, after a restart, Internet works again for about 20 requests.

So far, I have tried updating the firmware on the router, setting the MTU to 1500 instead of Auto, and giving my laptop a static IP address. None of these have done anything to help the issue.

The noise level doesn't seem too high (-120dBm). Some other things which may be relevant are that the access point is open (I want to try sharing my connection with whoever wants it), and I am in an apartment building near a university, so there are tons of wireless access points in the area.

I originally thought that it was a router configuration issue, but disconnect/reconnect not working and restarting working makes me thing it may be an ubuntu issue.

Here is the output of some diagnostic commands I ran:

david@david-ThinkPad-T410:~$ iwconfig
lo no wireless extensions.

eth0 no wireless extensions.

wlan0 802.11bg ESSID:"YouWouldntStealAnInternet" Nickname:"rtl8191SEVA2"
Mode:Managed Frequency=2.412 GHz Access Point: C0:C1:C0:AB:2E:42
Bit Rate=11 Mb/s
Retry:on RTS thr:off Fragment thr:off
Power Management period:0us mode:All packets received
Link Quality=100/100 Signal level=-51 dBm Noise level=-120 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

vboxnet0 no wireless extensions.

david@david-ThinkPad-T410:~$ ifconfig
eth0 Link encap:Ethernet HWaddr f0:de:f1:56:89:af
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:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:20 Memory:f2600000-f2620000

lo Link encap:Local Loopback
inet addr: Mask:
inet6 addr: ::1/128 Scope:Host
RX packets:3819 errors:0 dropped:0 overruns:0 frame:0
TX packets:3819 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:192710 (192.7 KB) TX bytes:192710 (192.7 KB)

wlan0 Link encap:Ethernet HWaddr 68:a3:c4:29:88:32
inet addr: Bcast: Mask:
inet6 addr: fe80::6aa3:c4ff:fe29:8832/64 Scope:Link
RX packets:13408 errors:0 dropped:0 overruns:0 frame:0
TX packets:13507 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:11017565 (11.0 MB) TX bytes:1947031 (1.9 MB)
Interrupt:17 Memory:f8918000-f8918100

david@david-ThinkPad-T410:~$ ping
PING ( 56(84) bytes of data.
From icmp_seq=1 Destination Host Unreachable
From icmp_seq=4 Destination Host Unreachable
--- ping statistics ---
5 packets transmitted, 0 received, +2 errors, 100% packet loss, time 4016ms

September 18th, 2011, 11:32 PM
Bumping this to get it back to the front page.
Edit: The Quality of Service settings on my router only apply to wired connections, so I can't favor my laptop over everyone else.

I'm just gonna try adding security, and see what happens.