Crosstalk is caused by the electromagnetic interference. Basically, a signal "crosses over" from one pair of cables to another, causing the signals to become unusable.
NEXT (near-end crosstalk) is a condition generally caused b crossed or crushed pairs of wires. The conductors inside the wires don't evan have to be exposed- but if the conductors are too close, the signal travelling on one wire can actually interfere with the signal on another wire. The "near-end" is a relative term, referring to the end of the cable being tested (as opposed to far-end crosstalk, or FEXT).
In a typucal RJ-45 connection, the crosstalk is actually at its highest level as data enters the cable.
You may occasionally see the term PSNEXT. This is short for "Power Sum Near End Cross Talk", and refers to the calculation carried out when a NEXT test is run. When the NEXT results for each pair of wires is added, the result is the PSNEXT value.
NEXT (near-end crosstalk) is a condition generally caused b crossed or crushed pairs of wires. The conductors inside the wires don't evan have to be exposed- but if the conductors are too close, the signal travelling on one wire can actually interfere with the signal on another wire. The "near-end" is a relative term, referring to the end of the cable being tested (as opposed to far-end crosstalk, or FEXT).
In a typucal RJ-45 connection, the crosstalk is actually at its highest level as data enters the cable.
You may occasionally see the term PSNEXT. This is short for "Power Sum Near End Cross Talk", and refers to the calculation carried out when a NEXT test is run. When the NEXT results for each pair of wires is added, the result is the PSNEXT value.
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