> Now I want to make the LAN secure and only allow DNS, HTTP 
> and POP access from the LAN to the WAN. So I delete the above 
> rule and add the following rules.and define the specifice 
> port given below

You will probably find over time that you need rather more rules than those
to deal with websites running on non-standard ports and so on.

I would say that as a bare minimum you will also need HTTPS (443), and SMTP
(25) if you want your users to actually be able to send mail.  You will also
need FTP (21) if your users are ever likely to download executables
(drivers, patches, etc.)

Regards,

Chris
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C.M. Bagnall, Partner, Minotaur
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