Ask MetaFilter questions tagged with cat5

How do you troubleshoot a cat-5 drop?

Loto — Mon, 14 Dec 2009 07:40:27 -0800

How do you troubleshoot a cat-5 drop? Background: I recently moved into an awesome basement apartment where internet access is provided by a cat-5 drop from the second floor where the router connected to Fios resides.

Problem: The drop doesn't work. Using a cheap cable tester the landlord and I discovered that only two of the four pairs were working. I thought maybe the jacks were the problem so I repunched both jacks following the T568A standard. Briefly, three pairs were now working with only one pair failing. After moving the wire slightly none of the pairs worked. The other drops in the house have the same problem. All patch cables used have been tested and verified to work. The RJ-45 jacks were replaced when I repunched everything. There are no visible breaks in the wire.

Question: So, now what? He offered to pull a new cable through the walls but I'd like to save him the hassle if I can. Since other drops to other parts of the house have the same problem I'm thinking it isn't the cable itself. At this point, all I care about is getting the cable to pass using the handheld tester. My only idea right now is to test the jacks with a multimeter. How do the pros go about troubleshooting something like this?

Help me show him the truth

arniec — Thu, 21 Aug 2008 12:15:16 -0800

Help me convince my friend of a basic networking truth. He sent me an e-mail saying he was assigning static IPs to all the devices on his home network so the signal would be stronger. More details inside: My friend has the following set-up: His cable modem goes to his router. His router feeds wall jacks throughout his house. In his basement is a single CAT-5 wall jack, but since he has several devices there he got a switch, so the wall jack goes to the switch, which then goes to his DirectTV and his XBox 360.

This worked fine in this set-up for months. But a couple weeks ago he stopped being able to receive On Demand programming. If he plugs the DirectTV right into the wall jack it works, but through the switch it does not.

He then assigned his DirectTV and his XBox 360 static IPs and the On Demand programming worked through the switch.

He believes the switch is causing weaker signal and the static IP is strengthening the signal to his DirectTV which, as an IT network tech, I know is NOT the case. And I've told him this but I cannot convince him that it's not a signal issue since he has seen the "evidence" that a static IP fixed the On Demand issue that a static IP didn't.

So (a) why would his DirectTV not work through a switch with a dynamic IP and (b) How can I explain in complete laymen's terms the fundamental networking essentials concepts of digital signal transmission through shielded twisted pair cable is NOT effected by the IP addresses being static or dynamic?

Bridge that Gap!

dance — Mon, 07 Apr 2008 06:24:12 -0800

In a similar vein to a previous question of mine, after successfully tackling that problem, I am now again trying to 'bridge that gap'. This time a neighbouring house in our community would like to be wired up for internet. The houses in our community are networking with telephone wire. A G.HDSL bridge/router in each house separates data from telephone and functions as a switch. Other hubs/switches/routers can be daisy chained off of it as normal.

This house is a little further away than the previous house (in that situation I ran a regular CAT5e cable through an 25m existing conduit from a switch in one house to a switch in the other) so I'm not sure if the maximum possible CAT5 length of 100m will cut it. I don't know the exact distance to the house. It's probably about 70m ATCF. In addition, there's no conduit this time so I've no idea how I'd work that angle.

What are my options?

- Wifi mesh with the highly recommended Open Mesh technology?
- Fibre? I know next to nothing about fibre for networks. I know it's a based on light, that it's a good thing for speed etc and is expensive. That's it.
- Outdoor CAT5(e)/6 strung up in the trees somehow?
- Attaching an identical bridge/router to the telephone cable in their house and seeing if data magically appears at the other end? I've heard someone very non-technical mention lack of capacity about this but that can be taken with a big pinch of salt.
- Rooftop wifi 'beacon'?
- Others I haven't thought of?

Thanks a lot

Painting Cat5 Cable?

cm — Thu, 31 Jan 2008 20:02:12 -0800

Do I need to do anything special to apply latex paint to cat5 cable or to coax cable tv cable? Do I need primer or anything of that sort?

Help me not make a fool of myself

fvox13 — Thu, 20 Sep 2007 15:33:10 -0800

I'm wiring my first network patch panel tomorrow! Any tips, suggestions, things to avoid? I'm also having trouble finding a good wiring diagram. This is for Cat5e UTP wiring. I already own all of the tools.

I don't want to have Monster Cable nightmares!

ostranenie — Wed, 05 Sep 2007 11:47:43 -0800

AVFilter: Can I extend HDMI over CAT5? No baluns or fancy equipment - just copper, baby! Is there anything special about HDMI / DVI / VGA cables that would prevent me from just splicing a few Cat5/Cat5e/Cat6 cables and video extension cables and make up some panels? I know there are boxes that will drive HDMI over one ethernet-ish cable, but let's stay I have access to unlimited Cat5 and I want a 50-ft. HDMI cable under $20. Can I tie-wrap three Cat5 cables in between the HDMI female jacks and create an "uber-cable"? I've done it with composite and S-Video over 50 ft. with great success, so I figure..why not a digital signal, right? But before I go slicing up cables and making promises, I thought I might ask over what the benefit is over buying "real" cables. Yes, I'm more willing to splice cables for a half hour than I am to pay $250 for a cable which appears to be nothing more than a fancy connector and some copper stranded wire.

Also I'm asking because of the egregious price differences in USB cables example given on this page (a $30 difference between two seemingly identical six-foot cables).

Thanks in advance!

How do I wire a network socket with 2 ports?

chillmost — Mon, 22 Jan 2007 02:15:17 -0800

If i want to install a network socket box in an office, each with 2 ports, how do I wire it? I have been tasked with wiring up a few newly available offices at my company in order to get them on to the network. I know how to do this for both ends of a CAT5 cable and I am no stranger to wiring up a simple network with a router and a few hubs and switches.

For this project however, I want it to look nice and pretty with this kind of network jack (German) installed on the wall. Each box has 2 RJ-45 jacks on it. I have searched and searched but I can not determine if there is a special way to wire this sort of connection.

Do I run 2 lengths of CAT5 to each box (thus doubling the expense of cable)?
or do I affix the end of one cable to the back and the internal wiring takes care of the rest?
Or, do I have to really use my brain and figure out how to carry 2 data channels over 1 length of CAT5, employing some sort of y-splitter cable?
something else?

I mention the idea with the y-splitter because I know that with 4-twisted pairs, it is possible, in theory, to be done but I'm not sure if it is practical or common in this situation. Would anyone with experience care to drop some knowledge about how this is done?

I called the place selling this but they (sales) weren't really helpful.
Da fragen Sie mich viel zu viel!

A $100 Cat5 tester?

Kwantsar — Thu, 04 Jan 2007 12:44:13 -0800

Please recommend a cat5/RJ45/network cable tester to troubleshoot existing wiring. I have three jacks (out of 25) that aren't working right; I don't know if they have ever worked right. I'd like to know whether the cable between the switch and the wall plate is broken, whether it is simply miswired, or whether I am missing something else.

I can't get inside the plates at the switch without moving heaven and Earth, there's not enough slack in the wire at the walljack end for me to visually inspect whether the wires appear correct (visually), and trying a crossover cable at one end (the obvious first guess) provides no relief.

Also, if I can get a good tester (within my budget) that will tell me whether the wiring can handle gigabit, that's a bonus.

Budget is about $100.

Telephone over Cat5: Is it possible without voip?

Freen — Tue, 21 Jun 2005 13:57:21 -0800

I'm setting up some telephone lines, and well, I really don't want to lay more wires than I have to. So this is the deal, I've got five telephone lines, and three telephone (rj11) jacks. We've just installed wifi, and so a number of unused ethernet cables. Is it possible to buy an adaptor that will allow me to use a cat5 cable to send plain old telephone over them? We have a room in the back where we have out ethernet switch and patch cables, as well as where verizon brings our telephone lines in. I want to be able to put in a jack, and then connect a patch cable from the rj11 telephone jack to the rj45 ethernet jack that goes from that location to the desk, then connect that cable(going from rj45 back to rj11) to a telephone, or fax machine.

I imagine there might be issues with electrical incompatibilities, or wiring incompatibilities, etc. If anyone has any ideas about other ways to do this without rewiring, I'd love to hear them.

Thanks!