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QUESTION: Real World Certifier vs
Certifier.
The Real World Certifier has many of the features of the far
more expensive certifiers, so what is the difference?
ANSWER:
A "Certifier" is typically a two piece test set that is
installed at the near end and the far end of a cable. The
unit at the far end transmits high speed ANALOG sine waves
across a broad spectrum
that are analyzed by the unit on the near end. Many tests
are performed and the results
of each test are normally reported as "Pass/Fail" with time and dB
measurements included. As a final result the cable is
"Certified" as a Cat 3, Cat 5, Cat 5e or 6. This capability
depends on the particular certifier (i.e. many certifiers
are not yet able to test to Cat 6).
A Real World Certifier uses digital testing techniques to
arrive at CABLE TYPE (Cat 3, 5, 5E, 6) and the speed
capability if the cable (10MB, 100MB, 1000MB). Further, the
Real World Certifier breaks its testing into two levels
termed "Level 1" and "Level 2". The Level 1 test uses the
Real World Certifier Main Unit on the near end and transmits
SIMULATED DIGITAL DATA to the Remote Probe Unit on the far
end. Many tests are performed and the results of most tests are reported as
"Pass/Fail". Other tests provide timing measurements
and Cable Typing (Cat 3, 5, 5E, 6). The
final result is a "Projected Speed" graph of the cable
(10MB, 100MB, 1000 MB). The Level 2 test is similar to the
Level 1 except the device on the far end is a hub, switch or PC. The
LAN device at the far end transmits REAL DIGITAL DATA that is analyzed by the Real World Certifier at the
near end. If the far end unit is a Gigabit switch or other
1000 MB device, the cable is tested for speed capabilities
with real data up to a Gigabit (1000 MB). As you might
suspect, Level 2 tests cans only test up to the speed
capability of the device providing the data. For instance,
if the far end unit is a 100MB device, then the Level 2
speed testing is limited to 100MB. Byte Brothers offers a
small, lightweight Cisco/Linksys
Gigabit switch for $125 for those who wish to test to a
Gigabit and do not have their own LAN device to drive the
cable. The
results are reported as "Pass/Fail" with certain tests
having time measurements included. The final result is
a "Confirmed Speed" graph rating the cable for its data capacity
(up to 1 Gigabit if a Gigabit hub switch or PC is used on
the far end).
The Real World Certifier also has capabilities not
normally found on other Certifiers. For instance, the
RWC1000 has toner/probe capabilities for locating wires in
crowded closets (a high quality probe is included). The Real
World Certifier can perform Port Scanning and Inline Port
Scanning of LAN devices. And the Real World Certifier can
transmit a Port Beacon to locate ports on the network.
QUESTION: Level 1 vs. Level 2.
What is the difference between Real World Certification
Level 1 and Level 2?
ANSWER:
Real World Level 1 certification features opens, shorts and split pairs testing
(including distance to the fault) along with propagation delay, skew, NEXT and NEXT (FAR),
and Cable Typing measurements.
Level 1 testing uses simulated digital signals to test the
cable. Use Level 1 for new cable installations or anytime a
LAN device (hub, switch, PC) is not available.
Level 2 testing adds real live data with the connection
of a real live data source (a hub, switch or PC) on the far
end. This adds an important element to its capability:
signal attenuation of live data. Adding this data
element to the other elements gathered in Level 1 testing
creates Level 2 testing. The end result of Real World
Certification Level 2 testing the display of speed graph
that certifies the data speed capability of the cable. Use
Level 2 certification when you want to test a cable with
real live data. Or if you are troubleshooting and want the
added benefit of using real live data. An example of Level 2
use is if you want to test the cable with the exact switch
that it uses in the network.
QUESTION: Cable testing vs Real World Certifying
I need a good cable tester but do not need to speed test my
cables and other devices. Is the Real World Certifier a good
choice?
ANSWER: Yes. The Real World Certifier performs all of the
same tests of a high quality cable tester... and then goes
far beyond. For instance, you will find all of the standard
cable verification tests like LENGTH (with a real
one-nanosecond TDR), OPENS, SHORTS; WIRE MAP, and SPLIT
PAIRS (including distance to the split!). These might be all
you need at this point. But when you are ready, the Real
World Certifier also performs crosstalk testing (NEXT and
NEXT FAR), PROPAGATION DELAY (time for the signal to transit
the cable), SKEW (time delay netween pairs), Cable Typing
(Cat 3, 5, 5E, 6) and
ATTENUATION.... along with the speed testing.
QUESTION: Port scanning vs Inline port scanning.
What is the difference between port scanning and inline port
scanning.
ANSWER: "Port scanning" involves connecting the Real World
Certifier to single LAN device and performing the Port Scan
test. The test deciphers the link pulse from the LAN device
and displays the "advertised" capabilities of the device
(speed, duplex, auto configuration, etc.). There is no
guarantee that when you connect this LAN device to another
that it will operate at its highest advertised speed. It all
depends on the compatibility of the two LAN devices.
With "Inline port scanning" you connect the Real World
Certifier to both LAN devices and perform the Port Scan
test. The test deciphers the speed and duplex that was
"negotiated" by the two LAN devices. This tells you the
actual operating speed of the link. For instance, a switch
with an "advertised" capability of 1 Gigabit (1000 MB), full
duplex connected to a PC with an "advertised" speed of 100
MB, full duplex should negotiate to the highest compatible
speed and duplex (in this case 100 MB, full duplex). The
Real World Certifier's inline capability will verify if this
is true.
QUESTION: Printer vs documentation tablet.
Does the RWC1000 have a printer attachment?
ANSWER: Documenting results is important and printers are
perfect for the job but they are bulky and expensive. Byte
Brothers offers a "Documentation tablet" that follows the Real
World Certification process precisely. The person performing
the test can check off the progress of the test, document
the location of the cable and affix a "PASSED" sticker to
the cable outlet or device. A tablet and PASSED stickers are
included with the RWC1000.
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