Firewall=Slow internet?

[sil3nc3]

I have an aluMac, and am connected to the internet wirelessly via Dlink DI-624 Router. I currently have both my firewalls switched on, as well as Little Snitch running. While they are going, my internet seems to slow down a lot. As soon as i remove the firewalls/little snitch, it speeds up again. is this normal?

 

[Amdahl]

Define firewalls.

And try testing each one individually to see if just one of them causes the problem.

 

[sil3nc3]

I use both the built in firewall, and also my router firewall.

I tried both individually, both with and without LS. My internet still slows down. It's not a lot, but it's noticeable.