Smurf Denial of Service Attacks

Due to an oversight on my part, I left my discard ping unchecked following some network issues I was working on. A routine check on GRC revelead this oversight. Now on my router logs I am seeing the following:

10/06/2008 21:13:20 **Smurf** 224.0.0.1->> XX , Type:0, Code:0 (from LAN1 Outbound)
10/06/2008 21:12:24 NTP Date/Time updated.
10/06/2008 21:07:18 **Smurf** 224.0.0.1->> XX, Type:0, Code:0 (from LAN1 Outbound)
10/06/2008 21:05:55 NTP Date/Time updated.
10/06/2008 21:04:11 192.168.2.100 login success
10/06/2008 21:03:21 **Smurf** 224.0.0.1->> XX, Type:0, Code:0 (from LAN1 Outbound)
10/06/2008 20:57:18 **Smurf** 224.0.0.1->> XX, Type:0, Code:0 (from LAN1 Outbound)
10/06/2008 20:53:21 **Smurf** 224.0.0.1->> XX, Type:0, Code:0 (from LAN1 Outbound)
10/06/2008 20:47:17 **Smurf** 224.0.0.1->> XX, Type:0, Code:0 (from LAN1 Outbound)
10/06/2008 20:43:20 **Smurf** 224.0.0.1->> XX , Type:0, Code:0 (from LAN1 Outbound)

A search on google reveals some disturbing information about denial of service attacks! Can anyone tell me how to get rid of this?

Malware, Spybot have revealed nothing more than some cookies to be removed. I have removed my IP address for security, but it normally appears where the xx is.

Thanks!

 

Follow up- I discovered that my PC had been used by a friend who did some downloading - it was infected with several copies of Win32 Trojan 32 which my Bit Defender Internet Security 2008 did not pick up or stop!! Kaspersky did not find these - but told me that Dekard System Scanner files were "dangerous" ??, Trend anti virus would not install on my machine and kept giving error messages, online scans with Kaspersky, Trend and houscall froze in mid scan each time.

10/10 to Avast Pro - I downloaded the demo version and was very pleased when it found all the problems in the boot up scan, I had also disable system restore and deleted the hiberfil.sys files.

Needless to say I will be converting to their software as soon as the demo period (60days!) expires!



I finally