PePLink Balance Series v4.0 User Manual
Page 98
Appendix B.
Routing under DHCP, Static IP, and PPPoE
The information in this appendix applies only to situations where PePLink Balance operates
with to a WAN connection under DHCP, Static IP, and PPPoE.
For information that applies to GRE, please refer to:
Section 10.4.1,
Routing under GRE via Network Address Translation (NAT)
Section 10.4.2,
Routing under GRE via IP Forwarding
B.1
Routing via Network Address Translation (NAT)
When PePLink Balance is operating under NAT mode, the source IP addresses of outgoing IP
packets are translated to the WAN IP address of PePLink Balance. Therefore, with NAT, all
LAN devices share the same WAN IP address to access the Internet (i.e. the WAN IP
address of PePLink Balance).
Operating PePLink Balance in NAT mode requires only one WAN (Internet) IP address. In
addition, operating in NAT mode also has security advantages because LAN devices are
hidden behind PePLink Balance, not directly accessible from the Internet, and, hence, less
vulnerable to attacks.
The following figure shows the packet flow in NAT mode:
B.2
Routing via IP Forwarding
When PePLink Balance is operating under IP Forwarding mode, the IP addresses of IP
packets are unchanged; PePLink Balance forwards both inbound and outbound IP packets
without changing their IP addresses.
The following figure shows the packet flow in IP Forwarding mode: