Tag Info

Hot answers tagged

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 ...


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 ...


10

Normally nothing has changed between the cables between SATA I,II and III. From the official SATA-IO document: The same cables and connectors used for current SATA implementations can be used to connect SATA 6Gb/s devices. SATA-IO recommends utilizing quality components to ensure data integrity and robust operation at the fast 6Gb/s transfer rate. ...


7

In a pinch you can use scissors. Just slide the cable into the groove of the scissors and slow twist the cable completely around to get a nice nick in the insulation. Then pull on the insulation and it should break free. See here: http://www.youtube.com/watch?v=cSzfbN83wAs But my long term recommendation is to grab this from Fluke:


7

No. Certification of cables requires specialized equipment - which is (as you discovered) quite expensive. Accurately measuring crosstalk at 500MHz+ isn't something that NIC hardware is designed to do. If it were, it would also be quite expensive. The real rub here is that a given NIC / switch port might negotiate even 10GE over cables that don't meet ...


7

Shielded Twisted Pair is used in very electrically noisy environments, and I've never actually seen it in use (partly because I've never run into Token Ring in the wild). But then, I'm not a network geek so my exposure is smaller than the pros. By electrically noisy, I mean running through areas with running motors (spinning magnets), near high voltage AC ...


7

Having configured a number of SmartUPSes with AP9606 in my time, I do not remember ever having had the need for an "APC-proprietary" serial cable. The documented pinout looks like a simple null-modem cable swapping the TX and RX pins: +-----------------------------------------------------------------+ | ...


7

Call someone at the far away place and have them read out the color order to you. Or walk over there. The max length of the cable is 100m...not that much exercise. Or better yet, cut that jack off and wire it properly. If the pairs are in the wrong order the cable can still work, but will confuse the next guy. If they were not wired with pairs in the ...


6

If you are connecting two GbE NICs, you do not need a crossover cable. GbE NICs auto-detect what's on the other end and transmit accordingly. That said, the answer to your question is "yes". You can have a point to point network that's 1Gb with a crossover cable as long as that cable meets all of the other requirements.


6

You can use functionality in managed switches to watch error counters on the suspect ports. Some switches have built-in "cable test" functions that can help (though I've never seen any that were able to do anything more than detect cable length and open pairs). Finally, you could use something like TTCP and netcat to push traffic over the suspect ports to ...


6

Yep. They're interchangeable. All SATA is backward (and forward) compatible.


5

Cable jacket stripping tools exist. I've always used something like this: It's got a screw that allows you to set the minimum diameter, so you don't cut past the sheathing.


5

Normally a crimping tool will have a section specially for stripping the outer sheath of a cat 5 cable. It looks like a notch that would accomodate the cable cut into one side with a blade on the other side.


5

As sysadmin1138 says, STP is used in electrically noisy environments. One common example is inside industrial machinery. e.g. Networked PLCs (Programmable Logic Controllers) will often be mounted inside the same cabinet as all the other electrical/electronic controls of a machine. This will include transformers, relays, solenoids and all manner of other ...


5

My rule of thumb based on years of building server rooms: Minimize cross-rack cabling as much as possible. The 300 port rack for the edge ports is far from full so you can place the edge-switches in the same rack. This keeps most of the cabling in the same rack. The 3 racks to the left: I presume those hold your servers. Fit a cheap gigabit switch in ...


4

These might be what you're looking for: http://www.homedepot.com/buy/electrical/voice-data-communications/platinum-tools/ez-rj45-cat-5-connectors-50-pack-67870.html


4

The short answer is no. The longer answer is, it depends on just what sort of testing you want to do. The reason is that the tests performed by the Fluke, and similar, devices cannot be done in software alone. Even the fact that the cable is plugged into a NIC, which is kind of necessary when using software alone, will preclude most meaningful tests. You ...


4

A cable modem will typically have higher downstream and upstream bandwidth than a T1, however you should be aware of the two major differences (one of which you've already mentioned): T1 lines typically come with a very strong service level agreement (SLA), and T1 providers take these very seriously (largely due to the T1's heritage as a telecommunications ...


4

Yes - if I understand you correctly. Nothing stopping you purchasing a patch-panel then running 48 CAT5's out of the back of the panel (punched in to the panel of course) in a bundle. You then just crimp RJ45 on the end of each of the 48 cables. If you want to keep the job to a minimum you could purchase 48 patch cables and hack the ends off of them, then ...


4

Generally speaking, if you mix "better" equipment with "lesser" one, your performance will be somewhere in between them, possibly even better than when using only lesser equipment: CAT6 cabling will not bump your speed up if you have 100 Mbit switches, but CAT7a cable could give you better EM shielding than CAT6a and thus reduce spurious network errors. So, ...


4

Please don´t view this as an answere because this is your personal choice depending on your circumstances and budget. I can describe you what we did some month before in a structure in a (I think) comparable size with very low budget. We have to manage around 5 distinct networks and had the same number of ethernet links between the racks distibuted in our ...


4

I finally found them. The cable is a firmware upload cable that came with our IOGEAR GCS1644 KVMs.


4

identify that TX is not connected There is nothing in the 802.3 standards up to 100BaseTX which would support such functionality. Of course, if you have control over both ends of the link, you could implement an echo probe which would be answered by the remote side. For 1000BaseT things are different - there would not be such a thing as a "TX pair" or ...


4

Well, it may be proprietary (in the sense of it being a non standard pinout), but you can find pinout diagrams if you know what you are looking for, and if you have a few inexpensive tools, you can also make one. Here's a fairly simple one: This is the 0024C model: +-----------------------------------------------------------------+ | ...


3

Although there's a comment that says this question is already thoroughly answered, I don't think it's complete without at least one dangerous tool: This puppy is not only highly likely to nick (or completely cut) the inner wires of the cable, if you put your thumb on the cable to hold it steady there's a good chance you'll give yourself a nice deep slash, ...


3

I haven't had any problems with 10m SAS cables, and if the ones you get are standards-compliant, (which they’re required to be, if they call themselves SAS cables) there wouldn't be. Speed or durability won't be impacted by cable length: the only issue you may run into would be signal strength or error rate, but as you're staying within the length specified ...


3

I was very close to doing a similar thing with $dayjob. Most colocation centres - good ones, anyway, do rent roof-space, although these are usually used for satellite backhaul. I can't see why they'd mind putting TV satellite receiving dishes on their aerial space, provided that you're paying for it ;)


3

Ultimately the 'Cat-level' is something that your cablers test and sign off against, I'd leave it to them to do using whatever parts and testing method they like, they're the ones that's sign and support it so just let them do their job knowing you'll kick them hard if things fail. If you were planning on doing it yourselves/internally I think you've either ...


3

...the same as any other cable? Shortest distance to the side of the rack, strap it down, then shortest distance to the termination point strapped every 3/6/9/12 inches (depending on personal style). Typically you put the power cable (AC) on the opposite side of the rack from data cabling (DC) to avoid interference. Which side is data versus power is ...


3

We've had them lying around too. They're usually thrown in the box to give you serial console access to a wide variety of gadgets. Have a look for ISDN terminals, video projectors or UPS devices. Could even be a graphing calculator!



Only top voted, non community-wiki answers of a minimum length are eligible