User's Manual

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Appendix B About QoS
PLC 200AV allows for 4 levels of Channel Access Priority (CAP (0
– 3)). 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.
Default CAP
The ‘Default CAP’ group allows for default priority mapping of
packets that do not have a VLAN TAG. Settings are available for
Unicast (directed to a host).
IGMP - (default CAP 3) - sets the channel access priority for
IGMP frames - these are the group management frames, not the
stream data
Unicast - (default CAP 1) - sets the default channel access
priority for unicast frames not matching any other classification
or mapping.
IGMP managed Multicast Stream (Fixed to CAP 2) - sets the
default channel access priority for stream data belonging to a
snooped IGMP multicast group.
Multicast/Broadcast - sets the default CAP for multicast frames
not in a snooped group and for broadcast frames.