Moxa Technologies ETHERDEVICE EDS-308, Руководство по установке оборудования

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Switching, Filtering, and Forwarding
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.
EDS-308/309 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.
Switching and Address Learning
Moxa EDS-308/309 has an address table that can hold up to 1K 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, EDS-308/309 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.
Auto-Negotiation and Speed Sensing
All of EDS-308/309’s RJ45 Ethernet ports independently support
auto-negotiation for speeds in the 10BaseT and 100BaseTX modes, with
operation according to the IEEE 802.3u standard. This means that some
nodes could be operating at 10 Mbps, while at the same time, other nodes
are operating at 100 Mbps.
Auto-negotiation takes place when an RJ45 cable connection is made, and
then each time a LINK is enabled. EDS-308/309 advertises its capability
for using either 10 Mbps or 100 Mbps transmission speeds, with the
device at the other end of the cable expected to similarly advertise.
Depending on what type of device is connected, this will result in
agreement to operate at a speed of either 10 Mbps or 100 Mbps.
If an EDS-308/309 RJ45 Ethernet port is connected to a non-negotiating
device, it will default to 10 Mbps speed and half-duplex mode, as required
by the IEEE 802.3u standard.
Specifications
Technology
Standards IEEE802.3, 802.3u, 802.3x
Forward and Filtering
Rate 148810 pps
Packet Buffer Memory 256 KB
Processing Type
Store and Forward, with IEEE802.3x full duplex,
back pressure flow control
Address Table Size 1K uni-cast addresses
Latency Less than 5 μs