Deny ippp0, Firewall has blocked!

Hi Folks! This night I started my first firewall script and no I find something interesting in my log file. I am not sure wether I understand right what has happened. So here is the entry: Jan 11 11:36:15 linux kernel: Packet log: input DENY ippp0 PROTO=17 195.126.154.134:23116 217.0.41.97:6970 L=611 S=0x00 I=33417 F=0x0000 T=119 (#76) I am a newbie to this stuff, but I think it was a udp request from port 23116 of IP 195.126.154..134 (I looked up RIPE for this address) to Port 6970 of my (dyn.) IP. This took about 5 minutes, till it ended. L changed between 602 and 611. So what? Should I investigate more about this case, what happened, do I have to worry? Thanks and regards Uwe