Recently, my internet connection over wireless ( via a Netgear KWGR614 router ) has become unreliable, on both a Dell laptop running Ubuntu 10.04 as well as my Desktop running Ubuntu 10.10 . The problem does not seem to occur on a laptop running Windows Vista, nor on a Desktop running Windows 7 ( this machine is connected with an ethernet cable ). The problem does not seem to occur on my Openmoko Freerunner ( running Android 1.5 ), though I hardly ever use this device to connect over WLAN, so the problem may have just slipped by.

On my main Ubuntu Desktop, I have tried the following wireless devices:

• a Longshine PCI card ( an old device with an RTL8180L chip )
• a D-Link DWL-510 PCI card ( this device threw warnings in dmesg )
• a USB device from MSI ( US54EX ).

Usually my wireless network shows up in the network manager with a normal signal strength, even when the connection speed is slow or the connection gets reset ( asking me to click connect to re-authenticate my wireless connection ).

I have observed this problem with a Netgear KWGR614 Router ( with the manufacturers firmware ), as well as with a TP-LINK TL-WR741ND router running OpenWrt.

Taking a look at my routers logs, I find many instances of the following line:

Tuesday,04 Jan 2011 03:53:01 [TCP SYN Flood][Deny access policy matched, dropping packet]

I know that the Netgear router is susceptible to denial of service attacks, as I have previously been able to disrupt its operation by putting an nmap scan into a while loop. I use WEP or WPA to encrypt the wireless network.

Is it possible that someone is jamming my signal ?