Rev 4 May.17
47
9
9: Performance Tuning
9.1 Configuring Load balancing
When multiple cellular devices are configured as active WAN links, load balancing
can be used to control the amount of traffic transmitted over each link. This is useful
for example, when an alternative link has more bandwidth or lower costs are
associated with it than another link. In this case it may be desirable to direct more
traffic over this alternative link.
To use this feature, load balancing must be enabled on two or more WAN links, each
of which is assigned a "weight". The system then divides the value for each weight by
the accumulated total of weight values assigned to all links to determine the ratio for
distributing traffic (e.g. if link A is assigned a value of 50 and link B is assigned 100,
then link A's ratio will be 50/150=33% and link B's ratio will be 66%. In this scenario,
link B will handle twice as much traffic as link A.
To enable load balancing:
1.
Navigate to WAN > Links.
2.
Locate a WAN link to enable load balancing on and click Configure in the Actions
column.
3.
Set the Load Balanced option to enabled.
4.
Specify a weight.
5.
Click Save to save the WAN link configuration.
6.
Repeat these steps on at least one other WAN link.
Note: Load balancing is accomplished by randomly assigning TCP sessions or UDP packet
streams to connected WAN links participating in the load balanced group. Therefore, load
balancing is NOT link bonding (i.e. datagrams from a single session sent over multiple WAN
connections).
9.2 Setting Quality of Service (QoS)
Quality of (QoS) can be defined to ensure that certain applications or services receive
a minimum and/or maximum level of data transmission performance. QoS is
configured by creating networking rules for QoS prioritization. These rules can be
created for an entire WAN, individual WAN links, the entire LAN and/or individual LAN
segments. Since multiple rules can be created and also configured at these different
levels, care must be taken to ensure that QoS settings don't conflict.
Note that QoS policies are egress based. For example, applying a QoS policy to a
WAN interface is recommended to limit the bandwidth being consumed by video
traffic being viewed remotely. The oMG applies QoS policies to the traffic in the queue
for the WAN link before the traffic is encrypted. Therefore QoS also works for VPN
traffic.