Novell LINUX ENTERPRISE DESKTOP 10 SP2 - DEPLOYMENT GUIDE 08-05-2008 Deployment Manual page 748

nat
This table defines any changes to the source and target addresses of packets. Using
these functions also allows you to implement masquerading, which is a special
case of NAT used to link a private network with the Internet.
mangle
The rules held in this table make it possible to manipulate values stored in IP
headers (such as the type of service).
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