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Auto-Negotiation and Transmission Mode
Besides the transmission speed, each RJ45 port auto-negotiates the
transmission mode (half duplex or full duplex). Typically, if both devices
are set to “auto-negotiation”, the full duplex transmission will be set.
Note about possible loss of data packages in case of “Duplex
mismatching”
If the switch’s auto-negotiation port is connected to a non-negotiating
device, then the Switch will set its port transmission speed same as the
connected device but is unable to correctly detect the duplex mode. As
result the port is set to the correct speed but is using always the half
duplex mode as required by the IEEE 802.3u standard in such cases. For
correct transmission, the non-negotiating port must be set to half-duplex
mode (speed either 10 Mbps or 100 Mbps).
Switching, Filtering, Forwarding, Address
Learning
Each time a packet arrives at one of the switched ports, a decision is
made to either filter or forward the packet. Packets with source and
destination addresses belonging to the same port segment will be filtered,
constraining those packets to one port, and relieving the rest of the
network from the need to process them. A packet with destination
address on another port segment will be forwarded to the appropriate
port, and will not be sent to the other ports where it is not needed.
Packets that are used in maintaining the operation of the network (such
as the occasional multi-cast packet) are forwarded to all ports.
The Ethernet switch operates in the store-and-forward switching mode,
which eliminates bad packets and enables peak performance to be
achieved when there is heavy traffic on the network.
Switches of IE-SW-VL16 series have an address table that can hold up to
4K node addresses, which makes it suitable for use with large networks.
The address tables are self-learning, so that as nodes are added or
removed, or moved from one segment to another, the Ethernet Switch
automatically keeps up with new node locations. An address-aging
algorithm causes the least-used addresses to be deleted in favor of
newer, more frequently used addresses. To reset the address buffer,
power down the unit and then power it back up
WARNING
This equipment is intended to be used in a
restricted access location.
HOT SURFACE!! Before touching it, special
attention or protection is required.
