I have a 2821 router with the advanced Ip sevices K9 package installed which includes the IPS that uses the sdf's. The last update on the SDF according to the software download page is 10 Dec 06. However, there have been many subsequent signatures released. Should I take each subsequent signature release and incorporate into the SDF I have from Dec 10, or wait till the next SDF update comes out. If I do add the new signatures, could anyone tell me how this is done? I've never used this type of appliance before.