Planet MGSW-2402, Руководство пользователя

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Figure 3-10. Port Priority – 802.1p page
Programmable Mapping of 802.1p to Internal Priority
The received packets with 802.1q tag are assigned priority according to a flexible and
programmable mapping of the 802.1p user-priority tag (3 bits, value from 0 to 7) to the internal
priority queue. The default is to assign a packet to high priority queue when the 802.1p
user-priority tag is 4 to 7, and to low priority queue when the 802.1p user-priority tag is 0 to 3.
Please check the corresponding mapping checkbox to assign a high priority or uncheck that to
assign a low priority.
3.12 Port Priority- Type of Service
Each port can parse the header of an incoming IPv4 header and identify the Type-Of-Service
byte (TOS field). This is extremely important with the deployment of Microsoft Windows 2000
and the emerging DiffServ standard, which marks Voice-Over-IP and other real-time traffic using
this field. This feature provides Layer 3 QoS.
Figure 3-11. Port Priority – Type of Service
If this function of a port is enabled, then the most significant 6 bits of the TOS (these 6 bits are
also known as the DiffServ Code Point "DSCP" field, value from 0 to 63) are used to assign a
priority to the packet received from this port. Please check the corresponding mapping checkbox
to assign a high priority or uncheck that to assign a low priority.