Maximum permissible crossover cable length for direct Ethernet card-to-card connection

Question

I have a question, I can't find anywhere, what is the maximum permissible length of a crossover cable in the connection between two network cables?

Platon · Answer

Same as uncrossed.

PICIA · Answer

about 100 meters

turbolover · Answer

The length of the twisted pair / rj45 / ethernet: I have experience with efficient networks with a length of about 300 m (cables soldered several times along the way) and works at 100 Mbp / s

. Only four wires are enough, by the way, save money!

Application:
theory = theory
practice = practice
theory ? practice :!:

Moderated By jankolo:
I punish my colleague with a WARNING for writing out obvious nonsense

adikbo · Answer

In fact, standards are made to be broken! Why follow the recommendations of manufacturers and guidelines of standardization organizations !! After all, they are thieves and tricksters !! The standard specifies 4 pairs in a twisted pair, but two are enough - why buy more expensive cables?

Following your line of reasoning - why buy a Mercedes? Toddler rides too !!

The Ethernet standard allows 96 meters for a uniform connection + 4 meters for connections in patch panels and user connections.

greetings
adikbo

PS. The first two paragraphs are hypocrisy - the knife opens in your pocket when you read such "tips".

prez8s · Answer

Exactly, because I have a problem with edimax network cards, it is crap unmerciful, if the cable is longer than 20m, there is no connection, they do not even see each other, but on other power cables it is ok, those built into motherboards are already heaven better. Do not buy this crap, in the store they cost about PLN 16 / item, shit it is unmerciful. I am talking about it:

elektronik321 · Answer

These 4 pairs of wires are used in 1Gbits networks where there must be 8 wires, and in 2 pair networks, if something happens with one wire, you can replace it with unused pairs. building new network 100 mbits / suddenly everyone goes to 1 gbits you have to cut walls to replace all cables

starob · Answer

Of course, the whole pair is not just one strand.

turbolover · Answer

There was no gigabit only about 100Mbps. 2 pairs are enough without any problem. This "swapping" is just nonsense. For what? As she was already alive, it is possible, but the probability is extremely low!

I do not agree with the warning, I am writing about what I know. I have been working with networks for several years and I do not wish criticism from the theoreticians. The fact that a colleague is a moderator does not mean that he knows everything about everything. A little humility towards practitioners!

Elektryk80 · Answer

I agree with the previous speaker. He also works on building a network, I connect buildings and I know that 100m is not the limit! Of course, with a cable of poor quality, there is no need to combine it with lengths (sometimes even 60m or less are losses), but the devices also need good parameters. I know that the 8-port "Compex" switches connected to the 8-port with each other with the "madex" cable work flawlessly even on the 170-180m section.
4 pairs in a twisted pair are a good solution because on one cable you can easily run two computer stations, or in the event of failure of one pair or even two, you always have a spare two more and you do not need to replace the cable.
greetings

prez8s · Answer

and I do not agree with the previous speaker, the topic is about crossover cables, I checked and the 4-core cable is not suitable, there are errors, packets are lost, maybe in straight cables it will be ok, but not in crossover cables.

marian1977 · Answer

Remove the twisted pair insulation (and possibly the shield in ftp) on the 10m cable, unroll the special cables so that they all go straight, pinch the ends, you will see if it will walk. I guess it's normal that 100m is a deprecated value, but let's not exaggerate. Turbolover can be seen for a really nice couple of years you've been in the networks since you write the Mbp / s unit.

prez8s · Answer

So you want to say that usually untwisted wires will be ok? Boshee, people like you do in networks, give it a rest, because then they will have to correct you for you and you will make a laughingstock for yourself. Although I do not start a network, I have the appropriate professional qualifications and I have experienced a bit with networks, so that I can write such fucking, to develop a twisted pair, it does not fit in my head . Try using such a cable to play a video stream, for example a divix .... All you need to do in a good quality cable is mistake the wires when crimping and you will have transmission errors !!!!!!!!!!!!!!!!!! much less unwinding the twisted pair This is the laugh in the room

woogoo111 · Answer

And I will agree and disagree ... at the same time !!!!

I agree that the theory does not coincide in practice, and I will not agree with breaking the standards.
Not that someone writes this "nonsense" to stretch and rip the money (although probably also), but probably also to guarantee any quality, reliability and compatibility. So what if the net will become unusual, on 300m, or on one pair. In five years, something will "shake" and even the contractor himself will have a problem with finding the fault, not to mention someone who will have to rummage in such a structure after him.

Granted, you can not use the standard, but I think you can't take responsibility in that case, and a little bit of information out there that something is unusual.

marian1977 · Answer

I was hoping that intelligent people (not offending anyone) would browse this forum and understand that it was ironic, but oh well. And the comparison of the conversion of veins with the unraveling of the twisted pair in general threatens your way of thinking.

prez8s · Answer

I close the topic, you only make points with hopeless posts, soon you will write that you have a net on a string from a binder. Greetings.

Maximum permissible crossover cable length for direct Ethernet card-to-card connection

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