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How far is too far?

N/A

How far is too far?

Just wondered whats the furthest you could be from the exchange to sucessfully achieve

8meg speed
6meg
4+ mbps speed

Just for the help of others,

thanks
13 REPLIES
James
Grafter
Posts: 21,036
Registered: 04-04-2007

How far is too far?

I'd say you need to be within 1km to receive 8mbps sync speeds.

There's a graph around somewhere. Someone here is bound to know the link to it Smiley
N/A

How far is too far?

whats the max speed at around 2 and 3 km? Any ideas?
James
Grafter
Posts: 21,036
Registered: 04-04-2007

How far is too far?

How long's a piece of string? Smiley
N/A

How far is too far?

Between 2 and 3 km

Moderators note by James (sallyandjames) : Removed full quote of preceding post. link:rules
N/A

How far is too far?

Unless you want 8mb, it just depends on the local conditions. A longer line has the potential to pass through more sources of interference. Distance from exchange is only a useful indicator if you are in a built up area (and is therefore a useful indicator to the majoirty Smiley ).

At a *minimum* of 10km from the exchange:

ADSL Information (ADSL Firmware Version : 41e2be2c)
ATM Statistics TX Blocks RX Blocks Corrected Blocks Uncorrected Blocks
61603131 61603131 16974 276
ADSL Status Mode State Up Speed Down Speed SNR Margin Loop Att.
G.DMT SHOWTIME 448000 2240000 11.0 60.5

This line should be able to support an upgrade to 3meg. I wasn't around when it went Max and I don't think the router was plugged in throughout the testing. Maybe time to email Plus for an upgrade, although is there any point since they're now throttling usenet to a crawl?
chymorva
Grafter
Posts: 275
Registered: 29-08-2007

How far is too far?

Quote
Quote
How long's a piece of string? Smiley


Between 2 and 3 km


Tongue Tongue
N/A

How far is too far?

I get the full 8Mb/s at 1.5 km, and would get 10Mb/s or so according to my router if it wasn't limited. Probably 8Mb/s at 2 km max I would say.
N/A

How far is too far?

what about 3ish km, im most interested since this is what i have
Community Veteran
Posts: 1,160
Thanks: 1
Registered: 01-08-2007

How far is too far?

I'm just under 1.5 km from the exchange as the crow flies (so the cables are probably a bit longer than that) and sync at between 5.3 and just over 6 mbps. This gives a stable rate of 5 - 5.5 mbps.

It used to be mostly nearer 3 mbps but that was before BT (presumably!) did something or other that cleared my noisy line which they had previously denied I had.
Plusnet user since November 2003
Currently on Unlimited Fibre Extra and Unlimited UK & Mobile Calls
Plusnet Staff
Plusnet Staff
Posts: 12,169
Thanks: 18
Fixes: 1
Registered: 04-04-2007

How far is too far?

Here's the graph estimates:

http://www.internode.on.net/adsl2/graph/

About 1.7km for 8Mbps and 3.7Mbps for 4km.
Community Veteran
Posts: 1,229
Thanks: 1
Registered: 30-07-2007

How far is too far?

distance isn't the only factor. i'm <600m from (green) exchange, sync at 8, msr at 8, very good atten & snr margin but never speedtest at more than 5 (usually between 3 and 4) ... "contention" apparently :roll:
Plusnet Staff
Plusnet Staff
Posts: 12,169
Thanks: 18
Fixes: 1
Registered: 04-04-2007

How far is too far?

Distance and line quality are the main factors that will determine the line sync speed, but will have little bearing on the throughput speeds you see.

On a line that syncs at 8128kbps, the absolute maximum throughput speed you could see is 7150kbps because of the ATM overhead. In reality you probably won't see a lot over 6Mbps maybe 6.5Mbps, even off peak because of TCP overheads and local contention.

3-5Mbps is well within what BT will term as normal for Max, it might get a little faster overnight.
N/A

How far is too far?

But distance per se is not a huge deal. BT is getting off lightly because customers miles from exchanges automatically assume they are out of range when poorly maintained lines are the real culprit.

This line is for the most part rather old and around 10km long (it follows a single road so distance is easy to gauge) but has never the slightest difficulty with a 2mb connection, enjoys a relatively huge 10db of S/N margin (so it can weather temporary probs), and when not throttled is extremely efficient. That graph, while no doubt accurate for towns and cities is meaningless for rural installations and implies ADSL has an inherent hard distance limit waaaay below what can actually be achieved.

Does the SNR half for every mbit? It might be able to handle 4mbit although that wouldn't be very practical. I don't think it's sensible to risk the stability of the connection but I would be interested to know how far adsl can be pushed.

Results of a speed test (throughput not a huge way behind sync speed):

1.85 Mbps


Which means you can download at 236.58 KB/sec. from our servers.