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Standard User mossimo
(newbie) Thu 07-Jan-16 17:37:52
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63.5db line attenuation & snr


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I would be grateful if someone could give me some guidance on the following.

I live in a fairly rural area and itís unlikely that our line will be improved any time soon, so we wonít have the ability to get cable/fibre optic broadband. Therefore in an attempt to achieve faster speeds Iím contemplating upgrading the existing Zyxel modem/router given by our ISP and purchasing separate units. The question is, given my below stats, is it futile doing this given that my line attenuation is 63.5db and the SNR is 6.5db.Whilst no expert, and Iím happy to be corrected, I understand that whilst you can improve your SNR, your stuck with your line attenuation. If I go down the avenue of improving my SNR will I, in reality, see much improvement in speed given that I have such a high attenuation figure? Do the two go hand in hand?

upstream speed:864 kbps
downstream speed: 5056 kbps
relative capacity occupation: 98%
noise margin upstream: 6.0 db
output power downstream: 19.0 dbm
attenuation upstream: 31.5 db
carrier load: number of bits per symbol(tone)
tone 0- 31: 00 00 00 35 8a bb cc cc cb bb ba aa aa 99 88 76
tone 32- 63: 05 67 8a bc bc dd dd ae ee ee dd de ee ee de ee
tone 64- 95: 0e ee dd de ed dd dd dd dd cd cd cd dd dd dc cc
tone 96-127: cc cb bc cc cb ba bb ba aa 9a aa 99 a9 88 a7 99
tone 128-159: a8 89 80 88 87 87 78 74 25 70 46 65 05 66 66 54
tone 160-191: 20 02 44 44 25 54 55 54 45 44 44 32 24 24 34 22
tone 192-223: 22 22 23 02 00 00 00 00 00 00 00 00 20 00 00 00
tone 224-255: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
relative capacity occupation: 107%
noise margin downstream: 6.5 db
output power upstream: 12.5 dbm
attenuation downstream: 63.5 db
Standard User MHC
(sensei) Thu 07-Jan-16 18:42:30
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Re: 63.5db line attenuation & snr


[re: mossimo] [link to this post]
 
At first glance your downstream speed seems reasonable for a line with a minimum of 63.5dB - modems often only indicate attenuation up to 63.5 or 63 dB down and 31 or 31.5 up so I would guess your figure are even higher.

You cannot improve your SNR - that will stay at around 6db, what you can do is reduce noise or the potential for noise.

Install the modem at the closest point of entry. Use a filtered face plate. Keep all other electrical or electronic devices away from the hub and phone line.

That said, some hubs/modems will, on quiet and stable lines, move to a 3dB SNR figure which will give a little extra in terms of speed. One thing to consider is possibly buying an older BT Business hub - 2wire2700HGV (not 2701). They have an excellent reputation for working on long high attenuation lines.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

M H C


taurus excreta cerebrum vincit
Administrator MrSaffron
(staff) Thu 07-Jan-16 19:47:08
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Re: 63.5db line attenuation & snr


[re: MHC] [link to this post]
 
I'd go further and say 5056 kbps downstream sync is pretty darn amazing at 63.5dB or more, since that is 6km of line length and anything around 2000 kbps is normal.

A 5 Meg sync is beating lots of people who are closer to the exchange, suggesting you have a fairly optimal set-up already and thus I'd say just leave alone and carry on as you are.

The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.


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Standard User micksharpe
(legend) Thu 07-Jan-16 20:49:06
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Re: 63.5db line attenuation & snr


[re: MrSaffron] [link to this post]
 
... or use bonded/load-balanced connections if the OP can afford the cost.

Man does not control his own fate. The women in his life do that for him. -- Groucho Marx
Standard User Banger
(eat-sleep-adslguide) Thu 07-Jan-16 22:29:31
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Re: 63.5db line attenuation & snr


[re: MHC] [link to this post]
 
I think the OP is talking about tweaking his SNR maybe down to 3db but I cant imagine much gain in sync and may make the line unstable.

Tim
www.xilo.net & freenetname
Billion 7800 on 24 Meg LLU
http://www.thinkbroadband.com/speedtest/results.html...
Standard User mossimo
(newbie) Fri 08-Jan-16 14:10:07
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Re: 63.5db line attenuation & snr


[re: mossimo] [link to this post]
 
Thanks for taking the time to reply. Looks like under the circumstances I'm fairly lucky with the existing speed I'm getting. If I put my existing modem router into bridge mode and upgrade my router in order to gain better wireless coverage, will the existing modem keep the settings or will a reset occur? As I don't want to jeopardise them I don't know if I'm better just to leave it alone and look at achieving better coverage via the powerline wifi extender route
Standard User craski
(learned) Fri 08-Jan-16 14:20:57
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Re: 63.5db line attenuation & snr


[re: MrSaffron] [link to this post]
 
I would agree, that sync speed for line attenuation seems really good!

As a comparison, one of my lines has a downstream attenuation of 57dB and the best it syncs at is around 4000 Kbps with a 6dB SNR margin. Line length is about 7.5km.

Zen Unlimited Fibre Office BQM
Standard User RobertoS
(elder) Fri 08-Jan-16 15:55:15
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Re: 63.5db line attenuation & snr


[re: mossimo] [link to this post]
 
You could more cheaply and possibly more effectively connect a WAP to your existing router.

Re adding a second router, you don't normally do that the way you suggest, though it would work. And yes, you would lose the ISP login details which would need to be in the new one.

The normal thing people do is disable DHCP in the new router and adjust its own default LAN address to one on the original router's LAN. Making sure you give it one outside the original one's allocatable range, to avoid the possibility of two on the LAN with the same address.

As a bonus, both these solutions give you two access points, whereas yours would leave you with just one. A portable device such as a phone, tablet or laptop can move almost seamlessly between the two if walking around with it.

The indispensable man or woman passes from the scene, and what happens next is more or less the same thing as was happening before.
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Connection - AAISP Home::1 80/20. Sync 59997/15142kbps @ 600m. - BQM
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