The filter you have should look more like this
permit 0.0.0.0/0 0.0.0.0/0 udp dst eq 53
permit 0.0.0.0/0 0.0.0.0/0 tcp dst eq 25
permit 0.0.0.0/0 0.0.0.0/0 tcp dst eq 110
permit 0.0.0.0/0 0.0.0.0/0 tcp src eq 113
permit 0.0.0.0/0 0.0.0.0/0 icmp
deny 0.0.0.0/0 0.0.0.0/0 ip log
This will _only_ allow them to do
1) DNS Lookup
2) SMTP Mail
3) POP3 Retrieval
4) Authentication
It is then impossible for them to do anything else :)
Graeme
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FastLight Data Distribution cc - Your Internet 'Solution' Provider
Tel +27-(0)11-706-0212 Fax +27-(0)11-706-0812
Info : info@fast.co.za
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