Industrial ETHERNET

Industrial ETHERNET Lexicon
PSU
PTP
Public Key
Power Supply Unit. See also PS.
Precision Time Protocol. Protocol for
time synchronisation acc. to IEEE 1588,
with a precision of less than 1 µs.
See Private/Public Key
RIP
Routing Information Protocol
A protocol for the cyclic exchange
of routing tables between routers within
independent networks per broadcast.
RIP is one of the oldest, easiest and
most widely used routing protocols. The
successor of RIP is the more complex
OSPF.
QoS
Quality of Service
Term for a range of factors that have an
effect on the quality of a network. These
factors include network breakdown times,
delay times, stability of connections and
many more. For QoS, there is a series of
different definitions.
RJ45
A widely used plug connector in
telephone technology and in LANs.
It is also known as the Western plug
with 8 poles.
RADIUS
RAM
Remote Authentication Dial In User
Service. A RADIUS Server authenticates
a client, who registers for access with a
name and password. The password is
transmitted encoded.
Random Access Memory
Term for a volatile memory.
RMON
Remote Network MONitoring
A protocol for network management.
RMON defines new classes of data that
relate to and can be recorded on the
lower layers of the OSI reference model.
The data are then transmitted to a
network management station using Simple
Network Management Protocol
(SNMP).
RARP
RAS
Reverse Address Resolution Protocol
A protocol that delivers statically
allocated IP addresses to a MAC
address.
Remote Access System.
RMON 2
Remote Network MONitoring
A protocol for network management.
RMON 2 is an extension of RMON
and extends to higher layers of the OSI
reference model.
Redundancy
Manager
RFC xxx
Term for a switch or hub in a HIPER-
Ring that monitors the ring and in case
of an interruption in the ring structure,
activates the connection that has been
switched off upto that point. After
the interruption has been removed, the
redundancy manager again switches
this connection off. The ring is thereby
physically switched off, but from the
point of view of communication, it is
interrupted.
Request for Comments
An abbreviation that was coined
within the context of the Internet.
It is closely linked to the publication
of Internet standard.
Router
Routing
A device that works at Layer 3 of the
OSI reference model and connects
different segments of the network to
each other, or splits-up networks into
subnetworks. A router transmits only
data packets to other segments that
are sent to its own MAC addresses.
The router then sends the data packets
onward on the basis of routing tables. In
other words, the transmitting participant
must know that the receiver is not
located in the same network segment.
The transmitting station obtains this
information from the IP address of the
recipient. Routing tables are either given
as fixed tables or are given by the router
itself using routing protocols.
A function of Layer 3 of the OSI reference
model. A distinction is made between
dynamic and static routing. In dynamic
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