Return-path: Received: from mail-gw0-f51.google.com ([74.125.83.51]:48408 "EHLO mail-gw0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750726Ab1CFRb2 (ORCPT ); Sun, 6 Mar 2011 12:31:28 -0500 Received: by gwb15 with SMTP id 15so2108227gwb.10 for ; Sun, 06 Mar 2011 09:31:28 -0800 (PST) Message-ID: <4D73C4EC.7090702@lwfinger.net> Date: Sun, 06 Mar 2011 11:31:24 -0600 From: Larry Finger MIME-Version: 1.0 To: Ben Ruijl CC: linux-wireless@vger.kernel.org Subject: Re: r8712u: packet loss References: <4D5AAC7C.6060509@lwfinger.net> <4D5AC011.5050007@lwfinger.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 03/06/2011 03:52 AM, Ben Ruijl wrote: > Hi Larry, > > The iwconfig I sent you is wrong, because I switched routers. The > router I had was a wireless N router, with which I had 12 percent > packet loss. The iwconfig you are seeing is with a wireless G > connection and now I only have 1 percent packet loss: the same as you > have. It appears that the relative packet loss is greater with an N > connection. I have no idea why the loss should be greater with the N router than with the G router. How is the 2.4 GHz part of the N router configured? What make/model is it, and what firmware is it running? Do you have the latest version? My N router is a Netgear WNDR3300 normally running up to 270 Mbps at 5 GHz and 54 Mbps at 2.4 GHz; however, I changed it to run up to 270 Mbps in the 2.4 GHz band. Again, I get 1% ping loss. My iwconfig output is wlan12 IEEE 802.11bgn ESSID:"lwfdjf-n" Nickname:"rtl_wifi" Mode:Managed Frequency:2.422 GHz Access Point: C0:3F:0E:BE:2B:44 Bit Rate:270 Mb/s Sensitivity:0/0 Retry:off RTS thr:off Fragment thr:off Power Management:off Link Quality=97/100 Signal level=100/100 Noise level=0/100 Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:0 Missed beacon:0 That link gets an upload speed measured with tcpperf of more than 80 Mbps. I do not know why your N link is so lossy. The possible reasons are outdated firmware in the router that was established in the pre-N days, or you have noise/interference that affects the HT setup more than a simple G configuration. Larry