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Bill...Thanks a bunch. Looks Like I need to do some tweaking. - Don On Thu, 31 Mar 2005 13:02:42 -0500, William Arlofski <waa dash m0n0wall at revpol dot com> wrote: > Don Munyak wrote: > > What types of traffic are you blocking from a business perspective ? I > > am just curious about what traffic I might want to block in the LAN > > outbound direction..ie P2P, IM, 445 ports. > > When I set up a firewall for my clients, ALL outbound traffic is blocked > to start with. Then, individual ports are opened for specific, required > services, but usually only to specific external servers providing the > service. > > Outbound port 80 and 443 are opened for all clients for web browsing, > unless a proxy/caching server is installed at which time, those ports > are opened only for the cache server. Then, all client web-browsing > requests must pass through the proxy/caching server. Saves bandwidth and > provides logging, content filtering and auditing capabilities. > > Outbound FTP is opened when/if the client needs it. Same as above if a > cache server is on-site. > > Outbound port 25 is allowed ONLY for the internal email server. All > internal clients are set to use internal email server for sending email. > If there is no internal email server, then outbound port 25 is allowed > for internal clients, but only to their ISP's email server. This helps > to mitigate zombie spam machines from spewing out their crap without it > being logged locally or at the upstream ISP. > > Port 110/143 is only opened to their own, company run or > company-approved email server. Generally email on these servers has been > virus-scanned and/or filtered through RBLs and/or Spamassassin/Razor. > (oh and Outlook is discouraged whenever possible) > > Services like NTP, and DNS are opened ONLY for their internal NTP and > DNS server(s). All clients are configured to use the internal servers > for these services. > > Then, as needs arise (like sites that run web servers on NON-standard > ports) ports are opened as required. > > Paranoid? You bet. > > YMMV, but my clients are normally happy with these type of restrictions, > and actually never really even notice them since all services still work > as needed/expected. Plus with outbound blocking of all but necessary > services, they are being "good netizens" as well. > > Hope this helps. > > - > Bill Arlofski > waa dash m0n0wall at revpol dot com > |