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TEST & MEASUREMENT
"It can be stated that at any place where the
existing network infrastructure is subject to the
constant change of new technologies, modern
qualifiers should be part of the test equipment"
Active tests and troubleshooting
Another important aspect, apart from the pure qualification
of passive components, is that qualifiers allow for
troubleshooting active systems and for documenting
their state. In general, traditional functions are used for
this, which are well known and are preferred by system
administrators. The user needs to be able, for example,
to get an overview of the running network and to test
availabilities; for this purpose, the qualifier should be able
to connect to the active network and clearly display all
information about the capacity of the connected ports as
well as additional data such as DHCP server and gateway
address.
A comprehensive Ping test should be available for the
commissioning of new systems and the troubleshooting
of existing systems. If it’s possible to create a Ping list
containing IP and URL addresses, the user will be able to
verify the connectivity of a port at the touch of a button and
check whether all servers and printers needed for the specific
place of work are available. This is an important feature, in
particular for MACs (Moves, Adds, Changes) in the enterprise
environment.
Likewise, a specific search for individual devices is
possible. This quickly determines whether individual terminal
devices, such as email servers for instance, can be accessed.
When problems occur in the communication with the
outside world, the Trace Route function complementing the
Ping search is useful and provides information on the devices
on the route to the destination address, which can also be
located outside of one’s own local network. In this way,
problems to access the Internet can be uniquely identified
as either internal or caused by the provider.
VLAN identification and analysis
Today, large modern local networks are often subdivided
into smaller individual virtual unities using VLAN tags
(Virtual LAN tags). Well-equipped qualifiers can identify
these VLANs and display their IDs and priorities. To receive
more information on the individual switch ports, these
testers are able to perform an analysis of CDP (Cisco
Discovery Protocol) and LLDP (Link Layer Discovery Protocol),
whereas the content of information is highly dependent on
the switch used.
It can be stated that at any place where the existing
network infrastructure is subject to the constant change of
new technologies, where components are often renewed or
replaced, or troubleshooting needs to be performed, modern
qualifiers should be an integral part of the test equipment.
And where, for various reasons, certification of cabling
isn’t required, qualifiers are an indispensable alternative
to the class of certifiers, when it comes to the test and
documentation of the installed network. When choosing a
modern qualifier, it’s important that it combines all these
features to offer everything a network technician needs for
his job today – from the qualification of passive components
to the troubleshooting of installed networks. n
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