Industrial ETHERNET

= const.
= const.
Multiplexer
Attenuation:
Lmax = (Link Budget Reserve)/
fiber attenuation
Lmax = (11 dB-3 dB)/1 dB/km
Lmax = 8 km
Bandwidth length product
Lmax = Bandwidth/Signal bandwidth
Lmax = (500 km x MHz)/125 MHz
Lmax = 4 km
In this example, the maximum distance
to be covered is 4 km.
Signal bandwidths:
ETHERNET = 10 MHz, Fast ETHERNET
= 125 MHz and Gigabit ETHERNET
= 1.25 GHz
Input puls
Output puls
Term for devices or function units that
combine several channels of low capacity
into one channel of high capacity.
NIC
Network Interface Card
Term for PC insertion cards that enable
connection to an ETHERNET network.
NetBEUI
NetBIOS Extended User Interface.
Enhanced version of the NetBIOS
protocol used by network operating
systems such as LAN Manager, LAN
Server, Windows for Workgroups, and
Windows NT.
Network Nodes Term for network elements such as
hubs, switches and routers on which
different data transmission paths run
together.
Network
A general concept for the management,
Management configuration and monitoring of network
nodes and the devices connected
the same. The tasks of a network
management system may be subdivided
into error management, configuration
management, safety management and
performance management. To do
this, the network management agent
communicates with the network
management station using the network
management protocol SNMP.
Multiport
Bridge
NAT
A bridge that connects not only 2 but
several LANs together.
In ETHERNET LANs, multiport bridges
are also designated as switches.
Network Address Translation
Term for a protocol that is defined in
RFC 1631 and RFC 1918.
Network Mask
The network mask marks all bits in an
IP address for identifying the network and
the subnetwork. Also see IP address.
Binary notation
IP address 10010101.11011010.00010011.01011010
Network mask 11111111.11111111.11111111.00000000
->Subnetwork 10010101.11011010.00010011.00000000
Decimal notation
IP address 149.218.19.90
Network mask 255.255.255.0
->Subnetwork 149.218.19.0
Available address range
Host addresses 149.218.19.1 bis 149.218.19.254
Broadcast address 149.218.19.255
NAT-T
NAT-Traversal
NAT-Traversal. If there is a NAT-Gateway
inbetween two IPsec end points IPsec
does not work, as the IP-addresses of
the end points are also encrypted. NAT-
T solves this problem. NAT-T is enable
automatically during the handshake if
required (and supported).
NMS
Node
Network Management Station
See Network Management.
Term for a participant in a network.
NEXT
Near-End Xross Talk
A form of crosstalk in which signals of
participants that are located on the
same side of a twisted pair cable get
super-imposed.
NRZ
Non-Return to Zero
Term for a coding process in which the
electrical signals do not go back to
zero even when there is a sequence of
several logical ones.
NRZI
Non-Return-to-Zero, Invert on ones
Term for a coding process with inverted
NRZ signals.
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