Eurotech ZyWAN, Руководство пользователя

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ZyWAN - User Manual
84 110150-1001F
The following table lists the fields available in the Networking tab if Enable Port Forwarding is set to Yes .
FIELD EXPLANATION
Inbound Interface Enter the name of the network interface on which to monitor the
incoming connection to an IP port, such as eth0 or ppp0 . See
Understanding Network Interfaces on page 21 for a description
of the available interfaces on the ZyWAN.
Inbound Port Enter the port number of the incoming connection. Port
numbers must be a number between 1 and 65535.
Destination Address
Enter the numeric IP address to which the network traffic is
redirected. Each of the four fields must be a number between 1
and 255.
Destination Port Enter the destination port number to which the network traffic is
redirected. Port numbers must be a number between 1 and
65535.
Optional fields:
The following optional fields configure the firewall to filter
allowed incoming connections to the ZyWAN.
Permitted Source Port
Range
Enter the range of source port numbers allowed for the incoming
connection. Normally source ports are randomly assigned, so
this field should only be used when the source port is specified.
Permitted External
Network
Enter the numeric IP address, or range of addresses, which is
the source of the connection to the ZyWAN. Each of the four
fields must be a number between 0 and 255. For instance,
entering an IP address network of 172.16.11.0 limits incoming
connections from addresses 172.16.11.1 through
172.16.11.255.
Permitted External
Network Mask
Enter the subnet mask for the Permitted External Network .
Each of the four fields must be a number between 0 and 255.
Permitted MAC
Address
Enter the MAC address, in hexadecimal format, of a specific
computer which is allowed to make a connection to the
configured Inbound Port .
Enable NAT
Select Yes if you wish to enable Network Address Translation, also referred to as IP Masquerading. This
allows devices on one interface of the ZyWAN (‘internal’ side) to access the network on a second interface
(‘external’ side), typically to allow devices to connect to the Internet via a single external IP address. The
ZyWAN re-writes the source and/or destination Internet addresses in a packet as they pass through, so that
they appears on the external side as from a single IP address, but on the internal side there may be multiple
addresses which are hidden from the external network. NAT keeps track of outbound TCP connections and
distributes incoming packets to the correct machine.
The following screen capture shows the Nat Table if Enable NAT is set to Yes .