ZyXEL Communications USG-300 - V2.20 ED 2, Manual

Page: 424 / 1149

Chapter 19 NAT
ZyWALL USG 300 User’s Guide
424
Mapped IP
Subnet/Range This field displays for Many 1:1 NAT . Select to which translated
destination IP address subnet or IP address range this NAT rule forwards
packets. The original and mapped IP address subnets or ranges must
have the same number of IP addresses.
Port Mapping
Type Use the drop-down list box to select how many original destination ports
this NAT rule supports for the selected destination IP address (
Original
IP ). Choices are:
Any - this NAT rule supports all the destination ports.
Port - this NAT rule supports one destination port.
Ports - this NAT rule supports a range of destination ports. You might
use a range of destination ports for unknown services or when one
server supports more than one service.
See Appendix B on page 1009 for some common port numbers.
Protocol Type This field is available if Mapping Type is Port or Ports . Select the
protocol ( TCP , UDP , or Any ) used by the service requesting the
connection.
Original Port This field is available if Mapping Type is Port . Enter the original
destination port this NAT rule supports.
Mapped Port This field is available if Mapping Type is Port . Enter the translated
destination port if this NAT rule forwards the packet.
Original Start
Port This field is available if Mapping Type is Ports . Enter the beginning of
the range of original destination ports this NAT rule supports.
Original End
Port This field is available if Mapping Type is Ports . Enter the end of the
range of original destination ports this NAT rule supports.
Mapped Start
Port This field is available if Mapping Type is Ports . Enter the beginning of
the range of translated destination ports if this NAT rule forwards the
packet.
Mapped End
Port This field is available if Mapping Type is Ports . Enter the end of the
range of translated destination ports if this NAT rule forwards the packet.
The original port range and the mapped port range must be the same
size.
Enable NAT
Loopback Enable NAT loopback to allow users connected to any interface (instead
of just the specified
Incoming Interface ) to use the NAT rule’s
specified Original IP address to access the Mapped IP device. For
users connected to the same interface as the Mapped IP device, the
ZyWALL uses that interface’s IP address as the source address for the
traffic it sends from the users to the
Mapped IP device.
For example, if you configure a NAT rule to forward traffic from the WAN
to a LAN server, enabling NAT loopback allows users connected to other
interfaces to also access the server. For LAN users, the ZyWALL uses the
LAN interface’s IP address as the source address for the traffic it sends
to the LAN server. See
NAT Loopback on page 425 for more details.
If you do not enable NAT loopback, this NAT rule only applies to packets
received on the rule’s specified incoming interface.
Table 108 Configuration > Network > NAT > Add (continued)
LABEL DESCRIPTION