RFC 3022 Traditional/Unidirectional NAT

RFC 3022Traditional/Unidirectional NATNAT OverviewOriginally (RFC 1631 - obsolete) NAT provides a mapping between internal IP addresses and officially assigned external addresses. NAT is also known as IP masquerading.NAT 1:1 mapping between private & public ip addressesNAT overview

SNAT vs. DNATSource NAT (SNAT) The source address (/port) of the first (NEW) packet is translated The destination address of the return packet is translated correspondingly Destination NAT (DNAT)The destination address (/port) of the first (NEW) packet is translated The source address of the return packet is translated correspondingly

NAT Overview1 to 1 translations (NAT) assign a different IP address for each translationTraditional Nat (RFC3022)A single (or few) public IP address is mapped to multiple hosts in a private network Assign private addresses to the hosts of the corporate network NAT device modifies the port numbers for outgoing traffic Ports should be translated as wellTraditional NAT, RFC 3022 includes also port translation and is more correctly called NAPT: Network Address and Port Translation N:1 (private to public)NAT vs NAPTNAT The source address and/or destination address is translated NAPTNot only the address is translated but also the corresponding port