Industrial ETHERNET

Fault
+24V
+24V*
FAULT
P2 P1
Stand by RM
7 6
5 4
3 2
2
1 0
RM
Stand by
V.24
6
5 4
3 2
Stand by
7
1
Fault
+24V
+24V*
FAULT
P2 P1
Stand by RM
7 6
5 4
3 2
2
1 0
RM
Stand by
V.24
6
5 4
3 2
Stand by
7
1
is compared to the checksum received.
With this process, errors in the data
transmission can be detected.
FM 3810
US standard for the Safety of Process
Control Equipment.
FDB
Forwarding Data Base. Address table of
a switch for the decision at which port
to transmit a frame. The table assigns
MAC addresses to the port via which
the respective device can be reached.
The table is updated regularly (Aging).
Frame Relay Modified version of the X.25
protocol used in WANs.
FTP
File Transfer Protocol
A protocol on Layer 5 of the OSI
reference model for the transportation
of files.
FDX
See Full Duplex.
FTTD
Fiber To The Desk.
FDDI
Fiber Distributed Data Interface
A standard for data networks, that
covers the Layers 1 and 2 of the OSI
reference model. FDDI is originally
based on a double ring topology with
fiber optic cables as the transmission
medium.
Full Duplex
A mode of operation in which a device
can simultaneously transmit and receive
data. If a transmission path is operated
in full duplex in ETHERNET, the CSMA/CD
bus access process does not apply and
network diameter then depends solely
on the performance limits of the trans-
Fiber optic
In contrast to electrical transmission
mission and reception components used.
cable technology in which twisted pair
cables are used for data transmission,
glass or plastic is used as a transmission
medium for optical transmission techno-
RS2-FX/FX
RS2-TX/TX
i
LWL-Kabel
RS2-TX/TX
i
RS2-FX/FX
logy. Fiber optic cables come in the form
of multimode and single-mode fibers
2 x 10 Mbit/s = 20 Mbit/s
(monomode fibers).
Firewall
Term for protective measures that
LAN 1 LAN 2
partitions off a LAN from another
network, for example the Internet.
Flow Control
A function that in case of overload at
an output port, dumps packets at the
F/O
Fiber Optics
See Fiber Optic Cable.
input port or signals connected devices
to stop transmission. The signal to
stop transmission is sent in half duplex
operation by simulating a collision or,
in full duplex, by sending special
“Pause” packets.
GARP
Generic Attribute Registration Protocol
Term for a protocol family that is used
for exchanging parameters between
switches and Layer 2 of the OSI reference
model. At present there are the protocols
GMRP and GVRP.
Flow Controls
See Flow Control.
Gateway
A device that operates above the
FM 3611
US standard for electrical operating
equipment for explosion-endangered
rooms of the Classes I and II, Department
2, and Class III.
Layer 2 of the OSI reference model
and converts protocols. At Layer 3,
these devices are generally designated
as routers.
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