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23

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.us.com/Product%20pdf/Copper_Solutions/A6.pdf


22

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 are often used with many different types of signaling, including as examples voice and serial. In the second case, you can run Ethernet over coax, fiber, or ...


16

When you use TIA/EIA-568B on both sides this is a straight through cable. The colors of the inner jackets don't really matter, much the same as it makes no difference to the operation of the network if you use a network cable with a black or yellow outer jacket. However, the standard is in place for a real reason, and that is that the cabling system should ...


14

A hub is really just a powered cable that repeats every signal it receives on one interface to all the other interfaces. If two devices transmit at the same time to the receive of the hub interfaces, the hub repeats both signals at the same time to the transmit of all the other hub interfaces, and both signals received will collide at the transmit of the ...


13

UTP cables used in the 586 standard inherited their color code from the 25 pair color code developed by AT&T for cabling used in telecommunication purposes. The following table shows the combination of colors to be used for each pair This gives us this set of combinations: UTP cabling simply used the first four combinations. The order used in 586a ...


13

To understand this you need to understand the historical context. Originally Ethernet used a shared coaxial cable. Only one device could successfully transmit on this at a time. If two devices transmitted at the same time it was considered a collision. Then repeaters came along, to extend the distance and increase the number of nodes. A repeater would ...


11

Anything you choose to do will increase attenuation and potentially shorten the distance you can run PoE. There is no best practice answer to this as the best practice is to re-run the cable. Since you can't (or aren't willing to do this) then I would do one of two things, although I would still highly recommend running a new cable (you can use the old ...


11

BASE indicates baseband signaling - there is no modulated carrier, the frequency starts near zero and extends to a certain cut-off frequency. BROAD indicates broadband modulation - there is a wide frequency band with a number of carriers modulated with the data (similar to xDSL). The X in -TX or -SX stands for 4b/5b (100 Mbit/s) or (improved) 8b/10b line ...


10

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 no difference. It will require care, but you can identify the wires per pair by "ringing" them out with a multi-meter with a continutiy check ( the symbol ...


10

The first number represents the speed. If the next part is "BASE", then it is baseband. If it is "BROAD", then it is broadband. This is the original meaning of baseband/broadband, not the government idea (any speed at or above an arbitrary speed) of broadband. The last part is tricky. "2" means about (185) 200 meters. "5" means 500 meters. "36" means 3600 ...


9

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 needle nose pliers wrap it around the tip a couple times and then pull back it works perfectly. I have used it as a ripcord for more than 30 years. Granted on ...


9

Great question. In full duplex, there is a dedicated channel for traffic from "left to right" and a dedicated channel from traffic from "right to left": Therefore, in full duplex, collisions are impossible -- even if both NIC's transmit at the same time. In half-duplex, however, traffic in either direction is meant to only use the wire, one direction at a ...


8

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 specs mean you can do exactly what you're trying to do, and run two PoE cameras over a single Cat5e. First up, there are very, very, VERY few IP surveillance ...


7

It is actually a very trivial and straighforward reason. The standard starts with a single pair, two pins in the middle. This expands to a 4 pin plug for two pairs. What happens if you plan the pairs "straightforward" as you suggest? You break backwards compatibility with systems using only a centre pair. So you need to wrap the second pair around the ...


7

Short answer: you don't. 1000BASE-T requires Auto Negotiation to work - the fast link pulses are to be transmitted and received on specific pairs, compatible with 10BASE-T and 100BASE-TX. In theory, this requires the normal T586A/T568B crossover cable between two MDI ports or two MDI-X ports. Furthermore, the other two pairs would need to be crossed as well ...


7

Different types of Ethernet (standard Ethernet, Fast Ethernet, Gigabit Ethernet) have different speed of data transfer (10 Mbit, 100 Mbit, 1 Gbit). Why is that? Progress - technology advances. Including obsolete and brand new physical layers, Ethernet ranges from 1 Mbit/s to 400 Gbit/s. On the physical layer, the speed of electrical signals (voltage ...


6

Some distinctions and history: Ethernet and other networking systems can use a variety of physical media, including fiber optic and metallic wires. Since the wires are almost always made of copper, people usually speak of fiber vs. copper. The original 3 MBps Ethernet developed by Xerox in the 1970s used 50-Ohm RG-8/U coax cable. Later a version using the ...


6

Cat6 can provide Gigabit speeds up to 90+ meters. It is far more likely that one of the terminations is the problem. Gigabit requires the use of all 8 wires, so if one (or both) of the terminations isn't making good contact, then it could run at 100M which only requires 4 wires.


6

Yes, a patch cable will conform to one of the CAT standards. A CAT5e patch cable will use CAT5e cable, terminated with RJ45 connectors. The cable will be tested and will conform to the CAT5e standard. A CAT6 patch cable will conform to the CAT6 standard etc.


6

With twisted pair and a repeater hub, the hub is not much more than a digital amplifier. For that it senses a carrier from an incoming signal on one port and switches all other ports to output mode. In this output mode, any additional incoming carrier is a collision. This triggers a jam signal to propagate the collision and make the sender stop transmitting. ...


5

The IEEE 802.3 standards define certain L1 characteristics/operation, but do not define the connectors to use to connect the devices. For instance, while 802.3 does define that 100BASE-TX will use twisted pair cabling that must meet certain characteristices (attenuation, cross talk, etc), it does not define if this must be UTP or some variation of STP. It ...


5

No common usage cable is rated for exposure to the natural elements. If it isn't going to be used inside of a home or environment-controlled switching office, it either needs to be specially ordered, or carried inside of conduit which is tailored to the task. Not to say that it won't work, but rather that it isn't designed to perform under that duress. Even ...


5

Simply addressing the connectivity of Ethernet cable, for short one as long as you use the same pairs at the same position it's OK. For longer ones, you might have some crosstalk issue if you do it "however you want as long as it's the same pairs at both ends" TIA/EIA-568A & B are only conventions to help everyone work together with less headache, ...


5

The horizontal cable needs to be solid-core cable. this type of cable gives better performance, but it is much more fragile, and it needs to to terminate in a fixed location, and not be moved after installation. Patch cords use stranded cable, which have poorer performance, but they are much less fragile. The ANSI/TIA/EIA Commercial Building ...


5

It's theoretically possible if one of the computers has two network interfaces. Otherwise, how would you connect them all? But that would be a kludge at best. If you are actually thinking about doing this, don't bother. Network switches are very cheap.


5

Copper cable splices are not allowed. Cabling standards are set by ANSI/TIA/EIA 568 Commercial Building Telecommunications Cabling Standard. For instance, this is for copper cabling: Only one transition point or consolidation point between the horizontal cross connect and the telecommunications outlet shall be allowed, and bridged taps and splices are ...


5

Category-6a cabling is UTP (Unshielded Twisted Pair) cabling. If your cable has a shield, it is something else. Any shielded cable must be properly grounded. That requires connectors and equipment that properly ground the shield, at least on both ends. Improperly-grounded, shielded cable will be a problem because the shield will exacerbate the problems it is ...


5

10BaseT and 10BaseFx are standards of connectivity for Ethernet. 10BaseT defines the use of twisted pair cabling (UTP / STP) for Ethernet, that includes cable features, male (in cable) and female (in wall boxes) connectors, max distances, etc. 10BaseFx defines the use of fiber optics for Ethernet, including type of fiber, max distances, connectors (in ...


5

The usual way to do this is once you have properly set up your pathways (see ANSI/TIA/EIA 569 Telecommunications Pathways and Spaces) is to have a pull-string. You use the pull-string to pull the cabling from the WAO to the TR, or vice versa, from the loops in the box of cable. A part of what you pull is another pull-string. You are supposed to leave a 10' ...


5

I entirely agree with previous answer that you really want a professional outfit with the correct test gear to properly pull, terminate, label and test each wire. And redo anything that fails certs. You have to make sure you have good specifications though, and many of the expensive test manufacturers will provide good sample contracts (which more or less ...


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