restrict ip address

[Kevin O'Connor]

Is there a quick and easy way to prevent access to my system based on IP
address
What I need is an exclusion list that's easy to set up and up date by
none technical staff
Also does anyone know of an email filter that runs on FreeBSD to check
for words I'm trying to push FreeBSD for mail and web use with in the
local authority but keep coming up against people who want to use NT and
all the third party filtering software that cost the earth and is way
beyond the budget of most schools in the authority
Ta
Kevin

Kevin O'Connor
NetWork Support