NPG 85M LAN, Руководство пользователя

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Appendix C
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.
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).
I
IGMP - (default CAP 3) - sets the channel access priority for IGMP frames - these
are the group management frames, not the stream data
I Unicast - (default CAP 1) - sets the default channel access priority for unicast frames
not matching any other classification or mapping.
I
IGMP managed Multicast Stream (Fixed to CAP 2) - sets the default channel access
priority for stream data belonging to a snooped IGMP multicast group.
I
Multicast/Broadcast - sets the default CAP for multicast frames not in a snooped group
and for broadcast frames.
The following are the factory default settings for VLAN Tags and TOS Bits:
Default CAP
VLAN Tag
User riority
Default CAP Priority
TOS Bit User
Priority
Default CAP Priority
0
CAP 1 0 CAP 1
1
CAP 0 1 CAP 0
2
CAP 0 2 CAP 0
3
CAP 1 3 CAP 1
4
CAP 2 4 CAP 2
5
CAP 2 5 CAP 2
6
CAP 3 6 CAP 3
7
CAP 3 7 CAP 3