QoS
QoS requirements are different for various data types such as
streaming video or music, voice and raw data. To provide higher QoS
for streaming data, priority levels can be set using tags at the
beginning of data frames. Virtual Local Area Network (VLAN) 802.1p
priority tags on Ethernet frames are used to specify 8 (0 – 7) levels
of ‘user priority’.
The 200M HomePlug® AV to Fast Ethernet Adapter allows 4 levels of
Channel Access Priority (CAP (0 – 3)). Therefore, the 8 levels of
VLAN Ethernet tags must be mapped to the 4 levels of CAP priority,
where CAP 3 is the highest priority and CAP 0 is the lowest. CAP 3
priority might be used for voice and network management frames,
CAP 2 is used for streaming video and music while CAP 1 and CAP 0
are used for data. Mapping VLAN tags or TOS bits to CAP levels is
easily done using the VLAN Priority Mapping function on the QoS tab
window.
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