M-N Nat Or Multi Nat - THOMSON SpeedTouch Configuration Manual

4.4 M-N NAT or Multi NAT

Introduction
Multi NAPT example
E-NIT-CTC-20040716-0004 v1.0
A chosen set of inside hosts (M inside IP addresses) can be mapped to a set of
outside IP addresses (N outside IP addresses) for outbound traffic only. This feature
is called Many-to-Few NAT: M-N NAT (with M > N).
`
192.168.0.1
SpeedTouch
192.168.0.254
`
192.168.0.2
Src IP Dest IP Src port
192.168.0.1 30.0.0.1 5500
Src IP Dest IP Src port
192.168.0.2 30.0.0.1 5500
A pool of public addresses is used. The first host that wants to make a connection to
the public network gets the first address of the pool. The second host gets the
second address of the pool and so on.
NAT box Internal Mappings
Inside IP Ouside IP
192.168.0.1 20.0.0.1
192.168.0.2 20.0.0.2
POOL:
20.0.0.1-20.0.0.4
NAT enabled
TM
20.0.0.1
Dest port Src IP
80 20.0.0.1
Dest port Src IP
80 20.0.0.2
Figure 10: Multi NAT example

M-N NAT or Multi NAT

Dest. IP
30.0.0.1
30.0.0.1
Public
30.0.0.1
Dest IP Src port Dest port
30.0.0.1 5500 80
Dest IP Src port Dest port
30.0.0.1 5500 80
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