ES-CUTP and ES-FUTP Manual
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The switched RJ45 ports are full duplex and auto-sensing for speed. (See section 2.2). When
the connected device is 10Mbps, the switch adheres to all the rules of 10Mbps Ethernet configurations.
The 10Mbps users share a 10Mbps traffic domain and can “communicate with” 100Mbps users as well
as 100Mbps domain. Similarly, the 100Mbps traffic follows the rules of 100Mbps Ethernet and can also
communicate with a 10Mbps domain.
The ES-FUTP and ES-CUTP are plug-and-play devices. There is no software configuring to be
done at installation or for maintenance. The only hardware configuration settings are user options for
UPLINK on RJ45 port #1. Half/full duplex mode selection for the switched fiber port and can be set
through a switch accessed from the front of the switch. The internal functions are described below.
Switching, Filtering and Forwarding
Each time a packet arrives on one of the switched ports, the decision is made to either filter or to
forward the packet. Packets whose source and destination addresses on the same port segment will be
filtered, constraining them to one port and relieving the rest of the network from processing them. A
packet whose destination address is 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 needed for maintaining the
operation of the network (such as occasional multi-cast packets) are forwarded to all ports.
The ES switches operate in the store-and-forward switching mode, which eliminates bad
packets and enables peak performance when there is heavy traffic on the network.
Switching, Address Learning
The ES switches have address table capacity of 16K node addresses, and are suitable for use
in large networks. They are self-learning, so that as nodes are added or removed or moved from one
segment to another, the switch automatically keeps up with node locations.
An address-aging algorithm causes least-used addresses to fall out in favor of new frequently
used addresses. To reset the address buffer, cycle power down-and-up.
4.2
Auto-negotiation and Speed-sensing
All eight RJ45 ports independently support auto-negotiation for speed in 10BASE-T and
100BASE-TX modes. Operation is according to the IEEE 802.3u standard.
When a RJ45 cable connection is made, and each time a LINK is enabled, auto-negotiation
takes place. The ES switch advertises its capability for 10 or 100Mbps speed, and the device at the
other end of the cable should similarly advertise/respond and both sides will agree to the speed being
used. Depending upon the device connected, this will result in agreement to operate at either 10Mbps
or 100Mbps speed.
When the ‘
LINK/ACT’
LED is ON, steady ON indicates LINK with no traffic, blinking ON
indicates the port is transmitting / receiving. The port has auto-negotiated for operation. (If an RJ45port
is connected to a non-negotiating device, it will default to 10Mbps speed and half-duplex mode, per the
IEEE 802.3u standard).
4.3
FULL or HALF Duplex, manual selection for ES-FUTP Models
Port #2 or 2SW (the fiber port) has an “F - H” manual switch mounted on the front-left of the
switch. While in the “F” position for fiber, it forces full-duplex mode at 100Mbps. In the “H” position, it
forces half-duplex mode. (Note: While fiber port is used, the copper port #2 will be automatically
disabled.)
4.4
FULL or HALF Duplex, manual selection for ES-CUTP Models
Ports #2 have “FF - A” manual switch mounted on the front-left of the switch. While in the “FF”
position, it causes 100Mbps fixed full duplex only, which can be useful for using Fast Ethernet media
converter.
While in “A” position, both N-way switch port #2 support auto-negotiation and full-duplex mode is
advertised for the standard 802.3u auto-negotiation session on RJ45 switched ports.
