User's Manual

NEOBIT 1014VA ADSL Router User’s Guide Chapter8
3. Select a protocol to which this rule applies, or choose ALL.
This selection specifies which type of Internet communication
will be subject to this translation rule. You can select ALL if the
rule applies to all data. Or, select TCP, UDP, ICMP, or a
number from 1-255 that represents the IANA-specified protocol
number.
4. In the Local Address From and Local Address To fields, type
the starting and ending IP addresses that identify the range
of private address you want to be translated. Or, type the
same address in both fields.
If you specify a range, each address will be translated in
sequence to a corresponding address in a range of global
addresses (which you specify in step 5).
The address (or range of addresses) should correspond to a
private addresses (or addresses) already in use on your
network. These may be assigned statically to your PCs or
assigned dynamically using DHCP, as discussed in the Quick
Start.
5. In the Global Address From and Global Address To fields,
type the starting and ending address that identify the range
of public IP addresses to translate your private addresses to.
Or, type the same address in both fields (if you also
specified a single address in step 4).
6. Specify a Destination Address or addresses, Destination
Port (or ports), or both. You can specify a single value by
entering that value in both fields.
 Specify a destination address (or range) if you want this
rule to apply only to outbound traffic to the address (or
range).
If you enter only the network ID portion of the destination
address, then the rule will apply to outbound traffic to all
computers on network.
 Specify a destination ports (or range) if you want this rule to
apply to any outbound traffic to the types of servers
identified by that port number.
For example, if you do not specify a destination address,
but specify a Destination Port From/To of 21, then this
translation will occur on all accesses by your LAN to all
external FTP servers. That is, when one of your LAN
computers communicates with an external FTP server, the
source IP address in the packet headers is changed to the
public address, replacing the initiator's private IP address.
Port number assignments are maintained in RFCs
maintained by IANA. Common port numbers include:
20, 21—FTP (file transfer protocol) server
25—SMTP (simple mail transfer protocol) server
80—HTTP (World Wide Web) server
 Specify both a destination address (or range) and a
destination port (or range) if you want this translation rule to