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79

Depends on the router/switch. If it's "Managed" - Like decent Netgear, Cisco or HP Procurve, or has STP (Spanning Tree Protocol) or one of its variants enabled, there's a few seconds of absolute insanity, then the switch realises that there's a loop in the network topology, and blocks one of the ports. (I've only described the STP re-convergence as ...


46

Actually it's for pulling the outer shielding away from the inner wires. When you're punching down the cable you pull the fiber string down from the top of the cable and it makes a nice split in the outer shielding that allows you to pull the outer shielding down to cut it off without damaging the inner wires. Here's a video that shows the process: ...


36

For the same reason why the first and second pair are connected to pins 4, 5 and 3, 6: compatibility with telephone systems. In telephony main pair is the middle pair and second pair is the next one from middle (pins 2, 5 in RJ11 and 3, 6 in RJ45). If you're using Fast Ethernet or Ethernet, you can route telephone signal in regular cable and it will work ...


31

Here's what I do Label each cable I have a brother P-Touch labeler that I use. Each cable gets a label on both ends. This is because if I unplug something from a switch, I want to know where to plug it back into, and vice versa on the server end. There are two methods that you can use to label your cables with a generic labeler. You can run the label ...


30

This is an interesting question since I've never seen anything that authoritatively states the design decisions behind that choice. Everything that I've come across, whether on the Interwebs or from conversation with people smarter than me in this area, seem to indicate two possibilities: Future proofing Extra shielding Future Proofing By the time of ...


30

An unmanaged switch won't have the feature you're looking for and connecting two ports between both switches will create a switch loop, which will effectively render the switches and the network unusable. A managed switch should have the feature that you're looking for, which is called Link Aggregation (LAG). Before purchasing a managed switch make sure to ...


28

There's no telecommunication difference (e.g. noise, crimping, termination), just the sheathing. The difference is an electrical code safety issue. Regular network cable (i.e. non-plenum) is flammable, can catch fire, can spread fire, and emit toxic fumes when burning. Plenum quality cable is required for use if you run your cable in air handling spaces ...


27

Personally I would always buy cables and always do buy cables in large volumes. The reason for this is that unless you are making cables for home you are making cables for a business. It takes time to make cables and you are paying people/you are being paid by the organisation you are working for. Unless you are making them in very large quantities the ...


24

Doing a google image search for "cat5 pinouts" has plenty of others as well


20

During my attempts to trace the lines using a toner and probe, I noticed that the lines that are active have a very weak tone signal. It is so weak, I can't trace it. The other lines, however, I was able to trace without any issues. Anyone know why the signal is so weak? Is it because the line is active and data packets are watering down the ...


19

Question is a bit broad but i believe it's still valid for this site. A good initial site survey is very important. Depending on the scale of this, you may need a professional networking company to run the survey for you. I will assume that this has a learning purpose so i'll list what we do when we go to a new site. Disclaimer: a proper network survey is ...


18

This is a patch panel: From Wikipedia: A patch panel or patch bay is a panel, typically rackmounted, that houses cable connections. One typically shorter patch cable will plug into the front side, whereas the back holds the connection of a much longer and more permanent cable. The assembly of hardware is arranged so that a number ...


18

While I doubt there is not a universal convention for colouring network cables (we use yellow for staff lan, green for test lan, blue for voice, orange for fibre, red for firewall / public lan), it's more important that you: Define a standard that is relevent to your requirements Document, publish and publicise the standard Adhere to the standards In my ...


17

On an RJ-45 connector, there are 8 pins. Originally only 4 were used. Tx(transmit) and its ground, and Rx(receive) and its ground. If you used a straight through cable, the transmit pins would be connected to the transmit pins on the other device. The same would be true for the receive pins. Early networking gear wasn't "smart" enough to know that data was ...


17

I'm no expert either but I'm on board with what you've stated in your question. My opinion is that the vendor is giving you a snow job in order to make more money off of the job by selling you CAT6 cable. My recommendation is that unless you plan on moving to 10GbE (CAT6a cable needed) in the near future then stick with CAT5e. GbE (1000BASE-T) will happily ...


17

As you deduced, 6e is a marketing term that was used before the formal adoption of 6a. The "things" in question that have been modified generally have to do with the number of twists per inch and the existence/type of shielding on the cable. The question isn't really whether 6 vs 6e vs 6a will -support- 10GBaseT, but rather at what distance. Cat6 is ...


16

568B is a termination standard and has nothing to do with the cable itself. 568A is an alternate termination standard and not as widely used. Both perform equally the thing is you need to choose one and stick to it at a particular instalation so as to avoid confusion later on.


16

They're generally called "EZ-RJ45" ends. I find them to be a pain in the rear. They require a special crimper that cuts off the excess, and even when brand new and sharp, these crimpers do an inadequate job, requiring me to use an angle cutter to snip off the remaining pairs one-by-one, thereby negating any time saved by not needing to worry about cutting ...


15

Definitely go with fiber. The two buildings most likely don't have a common ground. Running anything with an electrical connection such as a CAT5 cable across that takes a risk of electrical surges due to the difference in grounds. I've seen a lightning strike one building and take out everything connected to a network in another building b/c they were ...


15

Yes, you can do this, if both switches support link aggregation (which goes by a variety of names such as bonding, NIC teaming, port trunking, etc.). You're unlikely to find this feature in consumer grade hardware or unmanaged switch. The answer to the question you referred to even specifically mentioned LACP, one common protocol for link aggregation.


15

You're limited to daisy-chain if you don't have spanning tree, as redundant links without spanning tree will cause a loop. LACP doesn't really do anything here, in your case it would only used for switch-to-switch redundancy and throughput increase. Mind that there is no point of using LACP unless switches in both ends understands the LACP protocol. My ...


14

Yes it can. I have my home ADSL modem line (RJ-11) plugged into an RJ-45 socket, which goes back to my BT master socket. They are fiddly to unplug though.


14

I can not make cables at a rate fast enough to compete with the prices from MonoPrice or Ziotek. The only exception I make is for cables that are particular long, that have to pulled through conduit or holes without connectors on them, or when exact size matters. In that case, I do my best to borrow a appropriate cable testing hardware to test my work.


13

You're better off using a tone generator/probe kit. It's going to be quicker in the long run and less prone to incorrect results. I would suggest using a different wiring contractor next time and specifiying that you need them to label the ports at the jack and the patch panel.


12

splattne has covered what a patch panel is, and why it's different to a switch. To answer the last part of your question: the reason that host network connections don't go direct to switches is generally to do with ease of management. For example, desk locations on an office floor can be cabled back to a wiring closet patch panel which is labeled with the ...


12

You got part of it right. I won’t go into the exact standards for each, but in general: Cat 5 is rated to 100 MHz, but was specified when only 10BASE-T and 100BASE-TX Ethernet was common. Both of those only transmit on one pair in each direction. Cat 5e is also rated to 100 MHz, but includes specifications for testing parameters important to 1000BASE-T ...


12

From experience we don't use the "cable management arms" because they just get in the way and impede airflow. That's just us though, you'll find lots of arguments for and against and its not a matter of right or wrong, it's matter of "right for you". Cabling: I like the idea that network cabling runs down one side and power the other where possible. Don't ...


11

The short answer re: how much cable to run and where to run it is: It DependsTM. I like having as few wiring closets as possible, with either copper or fiber risers interconnecting the wiring closets (more runs than you think you'll ever need), and minimizing the number of overall Ethernet switches.. Unless you have some compelling need for more Ethernet ...


11

Read the wikipedia articles on this stuff. There is no real advantage of cat6 over cat5e. Specifically, both can run gig ethernet the same distances and when you go to 10gig ethernet, neither is 100% guaranteed to work. If you want to be able to run 10gig ethernet over copper, you need a 100% cat6A cable plant, not just cat6. With cat6, you can run up to ...


10

You can use Cat5 for really short runs in a Gigabit environment, but it isn't recommended. Cat5e is fine in almost all scenarios, but if you're wiring from scratch, use Cat6, it's only fractionally more expensive. Good Wikipedia info here - particularly the link about "far-end crosstalk".



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