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70 votes

Is 30 Mbit/s fibre for WAN faster than 30 Mbit/s copper?

30 Mbit/s is the same speed, no matter if it runs over copper or fiber. However, there are important link parameters other than link speed/pure bandwidth, so there may be differences. First, latency ...
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42 votes

Does having a longer Ethernet cable slow your connection?

No, it will not slow down a connection, but you need to be aware of the maximum length of a copper connection which is 100 meters. This needs to include the length of your patching cable from the host ...
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34 votes

Does having a longer Ethernet cable slow your connection?

For all practical purposes, there will be no effect on the speed of your connection. There will be a very insignificant amount of delay due to long cables. This won't affect the maximum speed of ...
29 votes
Accepted

Why does an Ethernet cable have four pairs?

10BASE-T saw first light as StarLAN that made use of the already existing twisted-pair category 3 telephone cabling (instead of the dedicated coax that 10BASE5/2 required). That cabling standard ...
  • 72.8k
27 votes

Is 30 Mbit/s fibre for WAN faster than 30 Mbit/s copper?

30Mb/s is 30Mb/s, but ISPs usually sell you “up to 30Mb/s” because the speed of DSL technologies is highly dependent on the distance between your equipment and theirs. With fibre, you are more ...
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23 votes
Accepted

What is this thread-like material on this Cat6 U/UTP cable?

It is used to split the outer shielding away without needing to use a sharp object which could potentially damage the wires themselves. It is commonly called a ripcord. Image taken from http://netx....
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22 votes

What's the difference between an Ethernet cable and a UTP cable?

The accurate answer is that they are not Ethernet cables. The cables themselves are not limited to transmitting Ethernet, nor is Ethernet restricted to using just UTP cables. In the first case, they ...
  • 26.8k
19 votes

Is 30 Mbit/s fibre for WAN faster than 30 Mbit/s copper?

You might consider pointing out to your "network engineering professional" that the propagation delay in copper is LESS that that of fiber (in most cases). The difference between the two is ...
  • 63.4k
18 votes

Does having a longer Ethernet cable slow your connection?

Sort of, to a very tiny extent. The longer your cable, the higher latency you experience - gamers call this "ping" time. However, the effect is about one nanosecond per foot of cable, which is ...
  • 311
18 votes
Accepted

Why do I need a crossover cable to connect devices of the same type?

When you need crossover cables is often explained, but why is seldom explained. It has to do with the copper (often referred to as Ethernet) wire itself. In copper wiring, there are four pairs of two ...
  • 14.1k
18 votes

Is 30 Mbit/s fibre for WAN faster than 30 Mbit/s copper?

It doesn't appear that any one has explicitly addressed the reliability of transmissions over fiber vs copper. It may be true that, for example, your router is throttled to 30 Mbps, but the ...
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14 votes
Accepted

The maximum length of CAT6 for intranet network?

Per the ANSI/TIA/EIA 568, Commercial Building Telecommunication Standard, UTP cabling is limited to 100 meters. That length assumes up to 90 meters of solid-core (better performance, but fragile) ...
  • 94.6k
12 votes
Accepted

An easy yet effective way to test if existing network cabling will be ok for GbE?

A E said: OK @MikePennington, so what's the "right way"? Either hire a professional cable installer to check out your cable installation, or get something similar to a Fluke CableIQ. These meters ...
12 votes

Is 30 Mbit/s fibre for WAN faster than 30 Mbit/s copper?

Copper (ADSL or VDSL) specifies a maximum peak speed whereas fiber specifies a maximum average speed. My glass fibre (FTTH) connection is artificially limited to 50 Mbit/s average. At the start of a ...
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11 votes
Accepted

Why is the Ethernet Connection Symmetric?

The very first Ethernet standards were designed for using a single, shared coax wire. There's no benefit in making the connection asymmetric in any way. Additionally, network nodes are generally ...
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11 votes
Accepted

RJ45 Cable only has 4 wires

Your cable is not a proper UTP network cable as defined by TIA/EIA 568. In fact, the pairs used by the 10Base-T (10 Mbps) and 100Base-TX (100 Mbps) ethernet are 1-2 and 3-6. The 1000Base-T (1 Gbps) ...
  • 94.6k
10 votes
Accepted

How to create Ethernet cables when I cannot figure out color of cat 5e cable wires?

The colors are just there as an ease-of-use tool. What really matters from a functional standpoint is what cable is connected in the jack in what position. Electrically the colors of the wires make ...
10 votes
Accepted

Multiple POE over a single cable

I know this is an older question, hopefully you've solved it by now, but I wanted to toss in my two cents, for the benefit of future generations if nothing else. First of all, yes, ethernet and PoE ...
  • 116
9 votes

Why one of the pairs on Ethernet is not adjacent?

But why in both standards there is one pair that is not adjacent (pin 3 always pairs with pin 6)? This goes back to compatibility in phone system wiring. It is based on the TIA/EIA 568 standard. ...
  • 94.6k
9 votes
Accepted

Does having a longer Ethernet cable slow your connection?

The electric signal will be slowed down by a minimal amount (afterall it travels at 2/3 light speed, more exactly at 0.64c, the velocity factor), how much time does light take to travel for 100 meters?...
9 votes

Can a single optical fiber support full-duplex communication?

Can a single optical fiber support full-duplex communication? Yes. There are "BX" standards, e.g. 100BASE-BX, which use different wavelengths for send and receive. The transmit wavelength on one end ...
  • 94.6k
9 votes

Why is the Ethernet Connection Symmetric?

Q: Why is ethernet symmetric (when compared to ADSL's asymmetry). A: This is best explained by looking the technical reason for ADSL's asymmetry. Quoting directly from wikipedia: There are both ...
9 votes

What is this thread-like material on this Cat6 U/UTP cable?

Its called a ripcord and is used to cut thru the outer casing of the wire so you don't have to use a knife. To those who say it is not strong enough your not using it right. Grab it with a pair of ...
8 votes
Accepted

Two computers connected by straight through Ethernet cable, communicating with APIPA addresses

Nowodays, many ethernet interfaces are 'auto MDI/MDIX'. They detect the type of device connected and if needed reverse internally Transmit and Receive. This allow connection of 2 devices of the same ...
  • 18.5k
8 votes

Is 30 Mbit/s fibre for WAN faster than 30 Mbit/s copper?

Latency can make a connection seem to be much faster. As an example, typical HTTP traffic downloads a number of small documents that each fit in just a few packets. Even while typical page sizes ...
7 votes
Accepted

1000Base-T Ethernet limited to 100 m, why?

The 100 meter limitation comes from physics and the installed base of cabling. One hundred meters is a convenient length due to legacy specifications (10Base-T and 100Base-TX) since the installed ...
  • 94.6k
7 votes
Accepted

CAT7 Ethernet cable: order of wires in the clamp

Category-7 cable has not yet been recognized by ANSI/TIA/EIA. The only currently recognized cables are Category-3 (still talking about eliminating it), Category-5E, Category-6 (may not be recognized ...
  • 94.6k
7 votes
Accepted

What is "Twisted pair with loading" cable?

A twisted pair cable with loading is a cable that has added inductance. It is a cable used for voice lines. A long span of twisted pair wires acquires capacitance and that's the case with voice ...
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7 votes

Does having a longer Ethernet cable slow your connection?

I believe it can, but not in the way most people are thinking about. Most are thinking of the extra propagation delay through the cable itself. This is valid, but as people have already pointed out, ...
7 votes

Why do I need a crossover cable to connect devices of the same type?

This fact is applied only to the devices that don't have an auto sensing mechanism, which can detect the direction of the transmitted traffic on each pin of the 8 RJ pins. When connecting same type ...
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