CBL AirLaser IP100plus, Руководство пользователя

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7.18 Quality Of Service
If not all ports of the AirLaser work at 1000 Mbit/s, data must be discarded in case of "overload of slow ports".
This is the case for example, when a backup is connected via Fast Ethernet to the AirLaser, but the AirLaser
is connected to the network by Giga Ethernet. Is the link in backup operation and are now send more than
100Mbit/s data from the network to the AirLaser, a part of the data must be discarded by the AirLaser.
The AirLaser has the possibility to detect prioritized data and transmits them preferred. The AirLaser
supports prioritization according to IEEE 802.1q, as well as IPv4 / IPv6 based prioritization. If an Ethernet
packet contains both prioritization, only the 802.1q variant is evaluated.
Each port of the integrated giga ethernet switch has four output queues. Queue 3 has the highes priority,
queue 0 the lowest.
Assignment of 802.1q priority values to the four output queues of the switch
802.1q priority value 0x0 0x1 0x2 0x3 0x4 0x5 0x6 0x7
Output queue of the
switch port 0 0 1 1 2 2 3 3
Assignment of 64 DiffServ or Traffic Class values to the four output queues of the switch
DiffServ value 0x00 to 0x0F
(0 to 15)
0x10 to 0x1F
(16 to 31)
0x20 to 0x2F
(32 to 47)
0x30 to 0x3F
(48 to 63)
Output queue of the
switch port 0 1 2 3
The queues are processed by a weighted 8-4-2-1-scheme. This guarantees the queues a minimum
bandwidth
Queue 0 1 2 3
Bandwith 7,00% 13,00% 27,00% 53,00%
Flow Control is disabled on all ports.
Packets that the switch can not store or forward, according to the above described priority rules, are
discarded. If required, preferably low-priority packets are discarded so that high-priority packets can be
forwarded. The minimum bandwidth for the queues are definitely available.
The settings of the quality of service are not configurable.
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