MIEN5208 Series Managed Industrial Ethernet Switch
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Attention:
1.Auto-negotiation mode are all RJ-45 port default mode , when RJ-45
ports are all auto-negotiation mode , the connected equipment should also
use auto-negotiation Mode, otherwise auto-negotiation failed the Ethernet
switch ports will default half-duplex mode , lead to communication problem .
2.flow control is used to manage data transferring of two node points,
two node points must all support flow control is valid , If network equipment
do not support flow control , we suggest close that function.
3.Flow control can be started or forbid , default as forbid . Using flow
control will generate many pause ifybc, if quantity too large , may cause
pause ifybc storm ,so please choose flow control function carefully .
4.5.2. Rate configuration
The device provides port-based speed limits, including entry and exit
speed limits, as well as the ability to specify restricted message types. The
configuration page is shown in Figure 3-9. Users can limit the traffic of each
port's egress or portal to a fixed rate, ranging from 128Kbps to 8Mbps. The
device provides rate limiting in both directions, where the ingress speed is the
actual speed from other devices, such as a PC, to the switch port, and the
egress speed is the actual speed at which the switch port flows to the device. If
the inlet and outlet speeds of the connection ports of two connected devices
are simultaneously limited, the actual speed is the smaller of the two. The
restricted packet types include unicast packets, multicast packets, broadcast
packets, and all data packets. The options are as shown in the figure. Users
can configure them according to actual needs
Attention :
1. When the port reaches the specified rate, the switch does not
immediately limit the speed. This is because both the ingress and egress
have data buffers, and the real speed limit is only available when the buffer
is exhausted.
2. When using port speed limit, if flow control is enabled on both sides,
the speed change between devices will be a smooth curve. The switch
determines whether to/or discard the over-traffic message according to
whether the flow control is enabled.
3. When the port is used for rate limiting, if both sides of the
communication are enabled for flow control, the packet should not be lost.
The appearance of the packet loss is the transmission speed.
