Are there different quality cat5 cables ?

mp260767 · 15 Jul 2009 at 12:57

hi,

apologies for the noob question, but i've been having ongoing network issues whereby my speed has dropped by 0.5mb (line is only 2mb anyway so its a fair loss) and managed to limit it to the internal wiring.

Do i just get any cat5 cable or do i need to look for anything specific to make sure it does the best job it can.

needs to cover a distance of approx 25ft.

cheers.......

rick827 · 15 Jul 2009 at 13:06

There's slightly different types of Cat5, however from your post it sounds more like you're after standard telephone cable? As you'd use Cat5 from the modem/router to your PC which wont effect your line speed (I presume ADSL?).

What made you think its internal cabling? By connecting to the master socket, or?

tolien · 15 Jul 2009 at 13:09

If you're using it for extension cable, any cat5 will be more than fine so long as it's twisted pair (which is a requirement for cat5).

mp260767 · 15 Jul 2009 at 14:22

rick827 said:
There's slightly different types of Cat5, however from your post it sounds more like you're after standard telephone cable? As you'd use Cat5 from the modem/router to your PC which wont effect your line speed (I presume ADSL?).

What made you think its internal cabling? By connecting to the master socket, or?

the extension is standard telephone cable at the moment but as i understand it cat5 will do the job and be more reliable over the distance i need.

connected to the test socket and that is normal speed, got a new master socket installed after the original master went u/s.

borrowed an extension socket off a friend and speed is still the same, which leaves the extension wiring itself.

tolien said:
If you're using it for extension cable, any cat5 will be more than fine so long as it's twisted pair (which is a requirement for cat5).

thats what i wanted to hear, so theres no chance i could get the wrong stuff ?

.

Confused · 15 Jul 2009 at 14:50

Move the router next to the master socket, use longer length of Cat5 from router to PC instead.

mp260767 · 15 Jul 2009 at 15:21

Confused said:
Move the router next to the master socket, use longer length of Cat5 from router to PC instead.

no real way to do that as the master socket is right next to the front door with no space to site the router.

the gap between the front door and lounge wall is where the master socket is and its
literally the width of the master socket with about 20mm either side and no real space before theres a door for the lounge.

Yamahahahahaha · 15 Jul 2009 at 16:27

Cat 5, Cat5e plenum, Cat5e external.

Plenum is what you want to use indoors, low toxicity in the event of a fire.
Cat5e external is cladded for weather resistance.

leezer3 · 15 Jul 2009 at 18:15

mp260767 said:
no real way to do that as the master socket is right next to the front door with no space to site the router.

the gap between the front door and lounge wall is where the master socket is and its
literally the width of the master socket with about 20mm either side and no real space before theres a door for the lounge.

Screw it to the wall?

Done that with several switches here.

-Leezer-

westom · 15 Jul 2009 at 22:35

mp260767 said:
the extension is standard telephone cable at the moment but as i understand it cat5 will do the job and be more reliable over the distance i need.

You could make that 25 foot connection with lamp cord and have no discernable difference. However using Cat3 (or Cat5) wire is recommended.

That speed change says a problem has been created (assuming your speed number is below what the ISP should provide). Only way to find the source of that speed reduction starts with a different number: signal strength.

DSL is a radio wave that travels thousands of feet on wire. Your 25 feet would have near zero affect. However other things also connected to the wire can 'eat' that radio wave. So again, log onto the modem's server. Go to the web page that reports signal strength in dB. Report those numbers here for better analysis. And now we are ready to start the diagnostic procedure.

Your data speed numbers are the executive summary - say little that is useful. Failure analysis begins with signal strength numbers in dB. Get that far. Report your numbers. Then learn if and where to look to find a defect.

mp260767 · 16 Jul 2009 at 16:53

stats reported by the router are:

Line Attenuation 63.0 db 31.5 db
Noise Margin 13.8 db 13.0 db

no change from what they used to be.

godinman · 16 Jul 2009 at 20:05

dude, temporarily move your router close to the wall socket and then test your speeds. That'll tell you if its the cable extension or not

westom · 17 Jul 2009 at 04:18

mp260767 said:
stats reported by the router are: ...
Noise Margin 13.8 db 13.0 db

What speed are you paying for? 2Mb? Then a periodic high speed is something that sometimes happens. 13 dB is not great but should be sufficient. However, were you paying for 3 Mb?

You might increase that signal speed by using 13 dB as a benchmark - if something inside your building is causing a 2 or 3 dB loss.

Your DSL modem is best connected directly (temporarily) to the master socket. Everything else inside the building (temporarily) disconnected. (even all filters disconnected). Does that increase the 13 dB? If so, something inside the house has slightly degraded DSL. And now you have numbers to find that defect.

You probably will find nothing defective on your side of the Master Socket - those 13 dBs do not increase during that test. After confirming nothing that you own is causing a problem AND if your are paying for more than 2 Mb, then it is BT's problem to solve.

BTW, your DSL signal came thousands of feet from the DSLAM. Moving your modem ten or twenty feet closer to the master socket will make no difference.

mp260767 · 17 Jul 2009 at 09:48

cheers all, i'll have a go and see what differences come up.

tolien · 17 Jul 2009 at 12:07

13dB isn't a normal target SNR margin. If you reconnect the modem it'll either increase or decrease without changing anything at all. Do that before you mess about with the wiring, and keep an eye on the speed it connects at as well.

BTW, your DSL signal came thousands of feet from the DSLAM. Moving your modem ten or twenty feet closer to the master socket will make no difference.

Wrong. If the 10 or 20 feet of cable is poor quality (especially if it isn't twisted pair) it can make a hell of a difference.

However, were you paying for 3 Mb?

There isn't such a beast. You either get fixed rate 512kbps, 1Mbps or 2Mbps (in which case it won't connect at a slower speed, it just won't connect), or up to 8Mbps where it'll connect at as high a sync rate as it can at the target SNR margin).

What ISP is this? Your last umpteen posts have been from a Telewest IP, in which case none of this is relevant...

mp260767 · 17 Jul 2009 at 12:30

o2 home access, package shows as upto 8mb.

tolien said:
13dB isn't a normal target SNR margin. If you reconnect the modem it'll either increase or decrease without changing anything at all. Do that before you mess about with the wiring, and keep an eye on the speed it connects at as well.

will do.

westom · 17 Jul 2009 at 13:44

mp260767 said:
o2 home access, package shows as upto 8mb.

13 dB would be marginal for 8 Mb data transfer. But 25 foot even of lamp cord is much too short to significantly affect DSL service. 'Poor quality' wire is a uselessly subjective term. Wire gauge (diameter) and how wire is constructed (twists per centimeter or no twisting) are significant. Factors important on thousands of feet of wire. But minor for your current temporary connection at these low radio frequencies. Even lamp cord would work fine as a temporary connection.

Your concern is only the signal to noise ratio. 13 dB is your current number. Find anything to increase that number. A DSL modem will increase dataspeed since DSL modems repeatedly 'learn' what is possible based upon that noise ratio. Eventually locate that modem anywhere convenient with Cat3 wire which is considered more than sufficient for any DSL service.

13 dB explains why 8 Mb was not available. Implied by your numbers is too much noise; signal is sufficiently strong. Discover and correct anything that might ‘eat’ DSL signals. Start immediately by connecting the modem directly to a master socket with nothing else connected to learn what you own is 'eating' DSL signals.

tolien · 17 Jul 2009 at 14:09

If the sync rate is ~2Mbps, 13dB was never going to be enough to get you to 8Mbps without considerable instability.

westom said:
But 25 foot even of lamp cord is much too short to significantly affect DSL service.

Nonsense. Poor quality cabling (which is typically untwisted) can make plenty of difference, even if it is a few metres compared to the hundreds or thousands of metres of well-insulated, twisted pair, cable bound up with other cables between the NTE and the exchange and that's borne out by real world experience.

'Poor quality' wire is a uselessly subjective term. Wire gauge (diameter) and how wire is constructed (twists per centimeter or no twisting) are significant.

Well yes but most cables don't have those features advertised. Looking for "good quality" extension cable will usually mean both of those features will get covered sufficiently. There's even a standard for the number of twists per unit length which BT use in their installations (CW1308).

Factors important on thousands of feet of wire. But minor for your current temporary connection at these low radio frequencies. Even lamp cord would work fine as a temporary connection.

Again, nonsense.

Your concern is only the signal to noise ratio. 13 dB is your current number. Find anything to increase that number.

Get the sync rate down to 150kbps and the SNR margin will jump through the roof. Doesn't mean it's what you want.
With a rate adaptive service, you need to keep an eye on both the SNR margin and sync rate, because the two will vary inversely with each other so you might see a constant SNR margin and a sync rate which changes significantly.

Implied by your numbers is too much noise; signal is sufficiently strong.

Bzzt.

westom · 17 Jul 2009 at 16:25

tolien said:
If the sync rate is ~2Mbps, 13dB was never going to be enough to get you to 8Mbps without considerable instability.

Amazing how many will even distort what was posted to only argue.

13 dB would be marginal for 8 Mb data transfer.

It says the same thing. That 20 foot wire will have little effect We even have 8 Mb working with high S/N ratios on untwisted wire almost 200 feet long. One function of the modem is to compensate for each unique wiring connection. Most likely reason for a marginal S/N ratio is noise. Modem can only compesnsate for that low ratio by lowering the datarate (ie to 2 Mb).

Execute the test. Determine where the problem is. Ignore the many who only want to argue by even saying the same thing.

tolien · 17 Jul 2009 at 17:04

I didn't distort it? It's not marginal, it obviously wouldn't even connectand you're suggesting using poor quality cable on what's a long line having issues connecting at the speed it was before.

I'm not arguing for the sake of it, what you're posting is factually incorrect and would only serve to mislead. I guess the alternative is I delete your posts.

mp260767 · 17 Jul 2009 at 17:51

right, powered on tonight when i got home, noise margin downstream is varying between 13.0db and 13.7db, noise margin upstream and line attenuation are the same as posted previously but speed has gone up to 1.6 from 1.5 on the previous post.

EDIT:
so after it running at that speed for the first hour at home i then disconnected the router and reconected to get the following stats:

line Attenuation : up 62db down 31.5
noise margin : up 14.6db down 12db

speed is back down to 1.5.