EW50 Industrial LTE Cellular Gateway
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2.4 Port Forwarding
Network address translation (NAT) is a methodology of remapping one IP address space into another by
modifying network address information in Internet Protocol (IP) datagram packet headers while they are in
transit across a traffic routing device. The technique was originally used for ease of rerouting traffic in IP
networks without renumbering every host. It has become a popular and essential tool in conserving global
address space allocations in face of IPv4 address exhaustion. This product embeds and activates the NAT
function. You also can disable the NAT function in
[Basic Network]-[WAN & Uplink]-[Internet Setup]-[WAN
Type Configuration]
page.
Usually all local hosts or servers behind corporate gateway are protected by NAT firewall. NAT firewall will filter
out unrecognized packets to protect your Intranet. So, all local hosts are invisible to the outside world. Port
forwarding or port mapping is
function that redirects a communication request from one address and port
number combination to assigned one. This technique is most commonly used to make services on a host
residing on a protected or masqueraded (internal) network available to hosts on the opposite side of the
gateway (external network), by remapping the destination IP address and port number.
