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FEATURE BY FEATURE
COMPARISONS |
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REAL WORLD CERTIFIER (RWCs)
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HIGH COST CERTIFIERS (HCCs)
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| Shorts, opens, length, map
and cable quality. RWCs test for shorts, opens, length,
map and cable quality as required by IEEE/ISO/IEC 802.3
standards. |
Shorts, opens, length, map and cable
quality. HCCs test for shorts, opens, length, map and
cable quality as required by IEEE/ISO/IEC 802.3 standards. |
| Cable propagation delay
RWCs measure cable propagation delay and skew in nano-seconds.
Propagation delay is the time it takes for a data signal to
travel the length of the cable. Skew is the difference in
delay between pairs. A small skew insures that data, on each
pair, will arrive at the receiver at about the same time.
A large skew reading errors. RWCs meet IEEE/ISO/IEC 802.3 delay and skew specifications. |
Cable propagation delay
HCCs measure cable propagation delay and skew in nano-seconds.
Propagation delay is the time it takes for a data signal to
travel the length of the cable. Skew is the difference in
delay between pairs. A small skew means data, on each, will
arrive at the receiver at about the same time. A large skew
reading errors. HCCs meet
IEEE/ISO/IEC 802.3 delay and skew specifications. |
| NEXT RWCs test digital
Near End Cross Talk (NEXT) by sending high-speed-digital
signals on each pair and reading the response on other
pairs. RWCs display NEXT as Pass/Fail for 10 meg, 100 meg or
gigabit data rates. Headroom or margin is graphically
displayed for each speed. If a cable fault causes a NEXT
failure, the distance to that fault (such as split pair) is
displayed. This helps cable installers and network mangers
locate repairable cable legs. High-speed digital test
circuits run for many hours on a common low cost nine-volt
battery. |
NEXT HCCs test analog
Near End Cross Talk (NEXT) by sending high-speed analog
signals on each pair and reading the response on other
pairs. HCCs display NEXT in dB with Pass/Limits for Cat 5,
5E and 6 cables. dB readings help cable manufactures improve
their cable performance. No distance to cable faults that
cause NEXT failures is displayed. This makes it difficult
for cable installers and network managers to locate
repairable cable faults. High-speed analog NEXT test
circuits are very expensive and require large expensive
rechargeable batteries. |
| FEXT RWCs test digital
FAR End Cross Talk(FEXT) by bouncing digital signals off the
far end of the cable and measuring the response on each
pair. RWCs display FEXT as Pass/Fail for 10 meg, 100 meg and
gigabit data rates. The RWC graphically displays headroom or
margin at each data speed. The RWC displays distance to
faults that cause FEXT failures. Distance to fault (such as
split pair) helps cable installers and network mangers
locate and repair faulty cable legs. |
FEXT HCCs use a far end
test module to perform NEXT measurements on the far end of
the cable. The far end NEXT is reported to the user’s
display as FEXT. Using two high-speed analog test modules
effectively doubles the cost of an already very expensive
test instrument. FEXT is report in (cable manufacture
friendly) dBs. Again, HCCs do not provide cable installers
and network manager distance to repairable faults. |
Real Data. RWCs measure
cable losses with real data from hubs/switches/PCs
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Simulated Data. HCCs
measure cable losses with simulated data. Data is simulated
with sine waves of various frequencies up to 350 or 600
mega-hz. |
| Remote Unit. RWCs use
inexpensive hubs/switches/PCs to provide signals to measure
cables signal losses. |
Remote Unit. HCCs use an
analog test module to source simulated data, i.e. high-speed
sine waves, to measure cable signal losses |
| Two-sided. The RWC plugs
on one end of the cable, the hub/switch/PC plugs on to the
other end. The RWC receives and measures real data signal
levels. |
Two-sided. The HCC uses
a second analog test module on the other end of the cable to
receive, measure and display the simulated data.
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Data Display. RWCs read
and graphically display real data signal levels on all four
pairs. The graphs show minimum acceptable levels, of the
data, after cable losses.
“RWC Level 2” combines real data level measurements with
delay, skew, digital NEXT/ FEXT and map measurements from
the Level 1 tests to Real World Certify the cables speed as
10 meg, 100 meg or 1 giga-bit. All of these measurements are
also used to compute, the cables graphically displayed
margin or headroom. |
Data Display. HCCs read
and display simulated data signals on all four pairs. The
simulated data level losses are displayed in dBs.
HCCs list simulated data loss measurements with delay, skew,
analog NEXT/ FEXT and map measurements to Certify cables as
Cat 3, Cat 5, Cat 5E or Cat 6. Headroom is based on worse
case of above measurements. |
RWCs Test Single Network Ports
RWCs test for 10 meg, 100 meg and gigabit data rates and
full or half duplex.
RWCs measure data signal levels on up to four pairs. Data
levels are displayed graphically in percent of maximum.
RWDs check hot splits. RWCs locate split pairs on installed
cables without disconnecting or de-powering the remote
network port. This helps cable installers and network
manager find cable faults without having to take down a
network. |
HCCs Test Single Network
Ports
HCCs test for 10 meg and 100 meg with full or half duplex.
HCCs do not graphically display data signal levels.
Must unplug network ports and cables before testing for
split pairs.
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RWCs Test Inline Network Ports
RWCs display 10 meg, 100 meg and gigabit data rates and full
or half duplex of both inline ports.
RWCs display negotiated data rates and duplexes. The user is
alerted, if the two ports have non-compatible data rates or
duplexes. This helps system installers and networks managers
locate data-rate bottle-necks and non-functioning network
legs.
RWCs help installers and network mangers locate the far end
of a cable by sending audio tones or beacon signals on the
cable. Audio tones. |
HCCs Test Inline Network
Ports
HCCs do not have inline capabilities.
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