ZyXEL Communications SAM1316-22, User Manual

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Chapter 10 Switch Setup
SAM1316-22 User’s Guide
86
Priority Queue
Assignment IEEE 802.1p defines up to 8 separate traffic types by inserting a tag
into a MAC-layer frame that contains bits to define class of service.
Frames without an explicit priority tag are given the default priority of
the ingress port. Use the next two fields to configure the priority
level-to-physical queue mapping.
The device has 4 physical queues that you can map to the 8 priority
levels for outgoing Ethernet traffic. The device has 8 physical queues
that you can map to the 8 priority levels for outgoing DSL traffic.
Traffic assigned to higher index queues gets through the device faster
while traffic in lower index queues is dropped if the network is
congested.
Priority Level The following descriptions are based on the traffic types defined in the
IEEE 802.1d standard (which incorporates IEEE 802.1p).
Priority 7 Typically used for network control traffic such as router configuration
messages.
Priority 6 Typically used for voice traffic that is especially sensitive to jitter
(jitter is the variations in delay).
Priority 5 Typically used for video that consumes high bandwidth and is
sensitive to jitter.
Priority 4 Typically used for controlled load, latency-sensitive traffic such as
SNA (Systems Network Architecture) transactions.
Priority 3 Typically used for “excellent effort” or better than best effort and
would include important business traffic that can tolerate some delay.
Priority 2 This is for “spare bandwidth”.
Priority 1 This is typically used for non-critical “background” traffic such as bulk
transfers that are allowed but that should not affect other applications
and users.
Priority 0 Typically used for best-effort traffic.
Apply Click Apply to save your changes to the SAM1316-22’s volatile
memory. The SAM1316-22 loses these changes if it is turned off or
loses power, so use the Config Save link on the navigation panel to
save your changes to the non-volatile memory when you are done
configuring.
Cancel Click Cancel to begin configuring this screen afresh.
Table 15 Switch Setup (continued)
LABEL DESCRIPTION