👉 Why is Twisted Pair cabling the most popular type of Network Cabling?
The first blog post I ever wrote was a deep dive into Ethernet. In honor of that, my first Twitter Thread is going to be a subset of that article which answers the question above.
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#utp #networking
The first blog post I ever wrote was a deep dive into Ethernet. In honor of that, my first Twitter Thread is going to be a subset of that article which answers the question above.
0/12
#utp #networking
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There are two main reasons UTP (Twisted Pair cabling) become the most widely used network cabling.
Both reasons have to do with Electromagnetic Interference (EMI).
There are two main reasons UTP (Twisted Pair cabling) become the most widely used network cabling.
Both reasons have to do with Electromagnetic Interference (EMI).
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🅰️The first reason is that using a PAIR of wires greatly reduces the outbound EMI emission.
🅱️The second reason is that TWISTING them around each other greatly reduces the effect of inbound, or induced, EMI.
🅰️The first reason is that using a PAIR of wires greatly reduces the outbound EMI emission.
🅱️The second reason is that TWISTING them around each other greatly reduces the effect of inbound, or induced, EMI.
3/12
Ethernet cable uses 4 pairs of wires, and each wire within the pair sends the inverse voltage of the other.
Meaning, if one wire sends +5v, the other is sending -5v.
This is known as a "Balanced Pair", and is represented in Twisted Pair as the TX+ wire and TX- wire.
Ethernet cable uses 4 pairs of wires, and each wire within the pair sends the inverse voltage of the other.
Meaning, if one wire sends +5v, the other is sending -5v.
This is known as a "Balanced Pair", and is represented in Twisted Pair as the TX+ wire and TX- wire.
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The idea behind the Balanced Pair is if one wire is sending +5v, and "leaking" +0.5v of EMI, then the other wire is sending -5v and must be "leaking" -0.5v.
The EMI emission effectively cancels itself out.
This is why UTP uses Pairs of wires. 🅰️
The idea behind the Balanced Pair is if one wire is sending +5v, and "leaking" +0.5v of EMI, then the other wire is sending -5v and must be "leaking" -0.5v.
The EMI emission effectively cancels itself out.
This is why UTP uses Pairs of wires. 🅰️
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But why are they Twisted around each other?
Effectively, the twisting allows either wire to "take turns" being closest to various sources of other stray EMI.
Consider this illustration:
But why are they Twisted around each other?
Effectively, the twisting allows either wire to "take turns" being closest to various sources of other stray EMI.
Consider this illustration:
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The illustration depicts a pair of wires (blue and green), twisted around each other, passing by a source of EMI.
The EMI affects both wires, and more intensely as they approach the source.
The illustration depicts a pair of wires (blue and green), twisted around each other, passing by a source of EMI.
The EMI affects both wires, and more intensely as they approach the source.
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The blue wire is initially sending +50v, and it's Balanced Pair is therefore initially sending -50v.
To keep things simple, if we add the EMI at only the top and bottom of the twists, the resulting signal on either wire after passing:
Blue wire: -28v
Green wire: +72v
The blue wire is initially sending +50v, and it's Balanced Pair is therefore initially sending -50v.
To keep things simple, if we add the EMI at only the top and bottom of the twists, the resulting signal on either wire after passing:
Blue wire: -28v
Green wire: +72v
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But since both wires were affected roughly equally by taking turns being closest to the EMI, the difference between the Positive and Negative wires remained identical throughout. 🅱️
You can adjust those numbers to 0 on a number line to determine the original values:
But since both wires were affected roughly equally by taking turns being closest to the EMI, the difference between the Positive and Negative wires remained identical throughout. 🅱️
You can adjust those numbers to 0 on a number line to determine the original values:
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Of course, the numbers used above were greatly simplified in order to communicate the concept.
Typical EMI emission only affects signaling in the range of micro-volts (µV) — which is 1,000,000th of a Volt (V).
Of course, the numbers used above were greatly simplified in order to communicate the concept.
Typical EMI emission only affects signaling in the range of micro-volts (µV) — which is 1,000,000th of a Volt (V).
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But the concepts still remain true:
Because the original and inverse signals are being sent, the net outbound emission is canceled out, 🅰️
and ...
Because of the twists, both wires are equally exposed to the same amount of interference. 🅱️
But the concepts still remain true:
Because the original and inverse signals are being sent, the net outbound emission is canceled out, 🅰️
and ...
Because of the twists, both wires are equally exposed to the same amount of interference. 🅱️
11/12
When I first learned about that, I found it fascinating. And thought it would be worth sharing.
To learn more about Ethernet:
practicalnetworking.net/stand-alone/et…
When I first learned about that, I found it fascinating. And thought it would be worth sharing.
To learn more about Ethernet:
practicalnetworking.net/stand-alone/et…
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Also... this is my first Twitter Thread! Would love some feedback!
Too wordy? Too long? Too short? Want more? Want less? I'm all ears =).
Also... this is my first Twitter Thread! Would love some feedback!
Too wordy? Too long? Too short? Want more? Want less? I'm all ears =).
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