Network Address Translation (NAT)
6 NN40011-046 Issue 1.2 BCM50 Rls 6.0
single WAN IP Address is used, then the Single User Account (SUA) feature
can be used. If multiple IP Addresses are used then the Full Feature NAT
service can be used.
BCM50 NAT Modes
There are a total of five NAT modes on the BCM50 Integrated Router. Which
modes you can use depends on the number of WAN IP Addresses have been
issued by the ISP.
Single WAN IP Address
The following BCM50 Integrated Router NAT modes are supported for use
with a single ISP-assigned WAN IP Address:
Many-to-one: Many LAN Addresses are mapped to a single WAN IP
Address.
SUA Server: Forwards external requests for certain services –
essentially ports – to specific LAN IP Addresses. An example of this
would be an FTP Server (FTP uses port 21). External FTP requests
can be forwarded to the FTP Server IP Address.
Note: For the SUA Server rules to function, Firewall rules need to be set up to
allow e.g. FTP traffic through to the specified Server IP Address.
Multiple WAN IP Addresses
The following BCM50 Integrated Router NAT modes are supported for use
with multiple ISP-assigned WAN IP Addresses:
One-to-one: Maps a single unique LAN IP Address to a single unique
WAN IP Address. Only that LAN IP Address can access the Internet
Many to Many Overload: LAN IP Addresses are mapped to multiple
WAN IP Addresses on a shared basis.
Many one-to-one: Maps each unique LAN IP Address to each unique
WAN IP Address. You should ensure that there are as many WAN IP
Addresses available as there are LAN IP Addresses that require
external access.
Note: If the ISP assigns multiple WAN IP Addresses to the BCM50e/be/a/ba
but you do not want to use more than one, the Many-to-one modes and SUA
Server modes can still be employed.
