User manual
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Two types of flow control:
1. In the half duplex mode, flow control is through back pressure. It is to send a jamming signal to the
transmission source to reduce transmission speed.
2. In the full duplex mode, flow control generally follow IEEE 802.3x standard. Switch sends "pause"
to information source to pause its sending information.
Use flow control to control the data flow between the sending and receiving nodes can prevent
packet loss.
Polarity (MDI/MDIX auto-negotiation)
MDI-II (Medium Dependent Interface- II mode), is a kind of standard built by IEEE for RJ-45 UTP
cable of fast Ethernet 100BASE-T. II stands for parallel configuration. MDI-X (Media Dependent
Interface-x mode) and MDI- II is a kind of standard built by IEEE for RJ-45 UTP cable of fast Ethernet
100BASE-T. X stands for crossover configuration.
6.3.2 Bandwidth Management
The device provides port based speed limitation, including ingress and egress limitation. User can
limits communication flow of each port and quits the flow limitation of the port. User can choose a settled
speed, the range is: 64Kbps ~ 100Mbps. The type of port limitation includes all unicast, multicast and
broadcast. When the port speed reaches the appointed speed, the device will enable or disable flow to
limit the transmitting speed or receiving speed by flow control or discard the message.
（
Figure 6.3.2
）
The device provides both ingress and egress speed limitation. The ingress speed refers to the actual
speed from PC and other devices to the switch. The egress speed refers to the actual speed from the
switch to other devices. If ingress and egress speed of the connecting port between two devices are
limited at the same time, the actual speed will be the smaller value.
For example, the Figure 6.3.2 shows Port 1 limits the ingress speed only, the maximum speed of this
port is 20M, Port 5 limits both egress and ingress speed, the maximum speed of this port is 50M
