Proxy-based Firewall
¨Client interacts
with proxy
¨Proxy interacts with
server on behalf of client
¨Proxy can
authenticate users via
userid/password
¨Web, telnet, ftp
proxies
¨Can allow or deny
application-level functions eg. ftp put/get
¨Caching capability
in web proxies
¨Slower than
packet-filter firewalls