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Why does my ADSL connection only reach 1Mbps when my neighbours just a few blocks away reach 3Mbps with the same provider?

Someone suggested that it's likely that the local exchange is oversubscribed. Shouldn't the telecom invest in expansion? Are there other possible explanations?

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closed as too localized by Xavierjazz, Nifle, random Apr 28 '12 at 3:48

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

I would leave the part about this being in Spain, I've seen several complaints about internet speeds in small towns there. – lupincho Apr 24 '12 at 15:22
@lupincho: I already edited that away since it is not really relevant to the question. To Mark: people appreciate as head-on questions as possible on this site. Cf. "Everything should be made as simple as possible, but not simpler" :-) . – Daniel Andersson Apr 24 '12 at 15:26
Ok, cool; thanks for that. I'm fairly active on Stackoverflow but somehow imagined this place to be more chatty. :) – mark Apr 24 '12 at 15:53
up vote 5 down vote accepted

The issue is the number of feet of telephone wire from your jack to the central office. Even homes a block or two away can differ by thousands of feet of wire. For example, ADLS2+ typically achieves speeds of up to 20Mbps through half a mile of wire (1Km). Bump that up to 2.5 miles (4Km) and you're down to 2Mbps.

If there's sufficient demand, they can add remote DSLAMs to increase performance. That way, the DSL line terminates at the DSLAM instead of the central office. DSLAMs are commonly placed at large developments in rural areas to provide DSL service to the new development.

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Note: In some parts of the world, "central office" effectively means "local telephone exchange". – RedGrittyBrick Apr 24 '12 at 16:10
You're probably right but it seems odd as every town has 3mb except our little corner. I'm sure you can imagine it's pretty dire, especially as we work from home. – mark Apr 24 '12 at 18:29

"Shouldn't the telecom invest in expansion?" - will you pay them more if they do? Are there any local alternatives that are better? If not, they probably won't.

Connection quality (which can also influence acquired speed) can depend on physical factors, such as cable quality, general interference and distance to base stations.

It can also depend on the router/modem, but unless you have gotten hold of some antique equipment, these speeds should not be an issue (this is extremely common in the ~100Mbps range, though).

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Exactly, my guess is that they are the only option in town, so they don't have to invest in anything and everybody would still go with them. But what you can do is to ask them to check the line quality, especially if people nearby get much better speed. But that "few streets away" may make the difference between speeds depending on the distance to the telecom office, as said in another answer. – lupincho Apr 24 '12 at 15:20
You're right. If Telefonica, the monopoly telecom here, were to have competition they would I'm sure do something about it. We pay 60 euros a month for this I might add. – mark Apr 24 '12 at 18:31

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