ZyXEL 2WG Betriebsanweisung
Chapter 8 WAN and 3G Screens
ZyWALL 2WG User’s Guide
167
The ZyWALL's NAT feature allows you to configure sets of rules for one WAN interface and
separate sets of rules for the other WAN interface. Refer to
separate sets of rules for the other WAN interface. Refer to
You can select through which WAN interface you want to send out traffic from UPnP-enabled
applications (see
applications (see
).
The ZyWALL's DDNS lets you select which WAN interface you want to use for each
individual domain name. The DDNS high availability feature lets you have the ZyWALL use
the other WAN interface for a domain name if the configured WAN interface's connection
goes down. See
individual domain name. The DDNS high availability feature lets you have the ZyWALL use
the other WAN interface for a domain name if the configured WAN interface's connection
goes down. See
for details.
When configuring a VPN rule, you have the option of selecting one of the ZyWALL's domain
names in the My Address field.
names in the My Address field.
Load Balancing Introduction
On the ZyWALL, load balancing is the process of dividing traffic loads between the two WAN
interfaces. This allows you to improve quality of services and maximize bandwidth utilization.
See also policy routing to provide quality of service by dedicating a route for a specific traffic
type and bandwidth management to specify a set amount of bandwidth for a specific traffic
type on an interface.
interfaces. This allows you to improve quality of services and maximize bandwidth utilization.
See also policy routing to provide quality of service by dedicating a route for a specific traffic
type and bandwidth management to specify a set amount of bandwidth for a specific traffic
type on an interface.
Load Balancing Algorithms
The ZyWALL uses three load balancing methods (least load first, weighted round robin and
spillover) to decide which WAN interface the traffic for a session
spillover) to decide which WAN interface the traffic for a session
1
(from the LAN) uses.
The available bandwidth you configure on the ZyWALL refers to the actual bandwidth
provided by the ISP and the measured bandwidth refers to the bandwidth an interface is
currently using.
provided by the ISP and the measured bandwidth refers to the bandwidth an interface is
currently using.
TCP/IP Priority (Metric)
The metric represents the "cost of transmission". A router determines the best route for
transmission by choosing a path with the lowest "cost". RIP routing uses hop count as the
measurement of cost, with a minimum of "1" for directly connected networks. The number
must be between "1" and "15"; a number greater than "15" means the link is down. The
smaller the number, the lower the "cost".
transmission by choosing a path with the lowest "cost". RIP routing uses hop count as the
measurement of cost, with a minimum of "1" for directly connected networks. The number
must be between "1" and "15"; a number greater than "15" means the link is down. The
smaller the number, the lower the "cost".
1 The metric sets the priority for the ZyWALL's routes to the Internet. Each route must
have a unique metric.
2 The priorities of the WAN interface routes must always be higher than the dial-backup
and traffic redirect route priorities.
Lets say that you have the WAN operation mode set to active/passive, meaning the ZyWALL
use the second highest priority WAN interface as a back up. The WAN 1 route has a metric of
"2", the WAN 2 route has a metric of "3", the traffic-redirect route has a metric of "14" and the
dial-backup route has a metric of "15". In this case, the WAN 1 route acts as the primary
default route. If the WAN 1 route fails to connect to the Internet, the ZyWALL tries the WAN
2 route next. If the WAN 2 route fails, the ZyWALL tries the traffic-redirect route. In the same
manner, the ZyWALL uses the dial-backup route if the traffic-redirect route also fails.
use the second highest priority WAN interface as a back up. The WAN 1 route has a metric of
"2", the WAN 2 route has a metric of "3", the traffic-redirect route has a metric of "14" and the
dial-backup route has a metric of "15". In this case, the WAN 1 route acts as the primary
default route. If the WAN 1 route fails to connect to the Internet, the ZyWALL tries the WAN
2 route next. If the WAN 2 route fails, the ZyWALL tries the traffic-redirect route. In the same
manner, the ZyWALL uses the dial-backup route if the traffic-redirect route also fails.
1.
In the load balancing section, a session may refer to normal connection-oriented, UDP and SNMP2 traffic.