NetModule NB1800, Руководство пользователя

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User Manual for NRSW version 4.5.0.100
5.4.5. Quality Of Service
NetModule routers are able to prioritize and shape certain kinds of IP traffic. This is currently limited
on egress, which means that only outgoing traffic can be stipulated.
The current QoS solution is using Stochastic Fairness Queueing (SFQ) classes in combination with
Hierarchy Token Bucket (HTB) qdiscs. Its principle of operation can be summarized as ceiling the
max. throughput per link and shaping traffic by reflecting the specified queue priorities. In general, the
lowest priority number of a queue gets most out of the available bandwidth.
In case of demands for other class or qdisc algorithms please contact our support team in order to
evaluate the best approach for your application.
QoS Administration
The administration page can be used to enable and disable QoS.
QoS Classification
The classification section can be used to define the WAN interfaces on which QoS should be active.
Parameter QoS Interface Parameters
Interface The WAN interface on which QoS should be active
Bandwidth congestion The bandwidth congestion method. In case of
auto
the system will
try to apply limits in a best-effort way. However, it is suggested to
set fixed bandwidth limits as they also offer a way of tuning the QoS
behaviour.
Downstream bandwidth The available bandwidth for incoming traffic
Upstream bandwidth The available bandwidth for outgoing traffic
IP to ping (primary) An IP, which answers ICMP echo requests to determine the bandwidth
of the link
IP to ping (secondary) An IP, which answers ICMP echo requests to determine the bandwidth
of the link
When defining limits, you should consider bandwidth limits which are at least possible as most shaping
and queues algorithms will not work correctly if the specified limits cannot be achieved. In particular,
any WWAN interfaces operating in a mobile environment are suffering variable bandwidths, thus rather
lower values should be used.
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