NAT Port Mapping
B-17
Network Address Translation
NI_TCP_CLOSED
The connection is closed
NI_TCP_SYNSENT
The peers are in the process of connecting
NI_TCP_ESTAB
A connection has been established
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IPN IPLocal;
This is the IP address (in network format) of the peer host on the local net-
work (LAN). It is the entity that has been assigned a virtual IP address be-
hind the firewall.
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UINT16 PortLocal;
This is the port in use by the peer host on the local network (LAN). It is the
entity that has been assigned a virtual IP address behind the firewall.
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IPN IPForeign;
This is the IP address (in network format) of the peer host on the public
network (WAN). It is the entity that is on the physical network outside the
firewall.
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UINT16 PortForeign;
This is the port in use by the peer host on the public network (WAN). It is the
entity that is on the physical network outside the firewall.
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UINT8 – Protocol;
This is protocol in use by the NAT entry. It must be IPPROTO_TCP, IP-
PROTO_UDP, or IPPROTO_ICMP.
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UINT16 PortMapped;
This is the port in use by the router on its public (WAN) IP address. It is this
port that maps back to a specific local IP/port on the LAN.
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HANDLE hProxyEntry;
When a NAT entry is created as a result of a proxy filter being installed on a
specific port, the HANDLE to the proxy filter that spawned the NAT entry is
stored here.
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UINT32 Timeout;
This is time in seconds when the proxy entry will expire. The system
checks with a fairly large granularity, so the actual expiration can occur 10
to 20 seconds later. If this value is ZERO, the entry is static. A NAT entry
must be specified as STATIC when it is created. Setting Timeout to ZERO
will cause the entry to expire in 0 to 20 seconds.