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Who provides the Internet service to Internet Service Providers (ISPs)?

i need to learn two things. each is related to other a bit. The first one is, while our LAN speed is usually 100 Mbps or at gigabit levels(very big compared to WAN speeds), WAN speed for instance DSL connections are far less than this. However, we are able to download huge files at those Mb speeds. Isn't this weird? [my real concern is why WAN speed is lower than LAN speeds]

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marked as duplicate by Bob, Daniel Andersson, ChrisF, Mokubai, sudo Jul 21 '12 at 14:06

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

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If you want to ask a new question, do that. Don't edit and change the complete meaning of an existing question. Thanks :) –  Oliver Salzburg Jun 13 '12 at 11:05
    
As of the edit to add [my real concern is why WAN speed is lower than LAN speeds] (within the 5 minute free edit period at the beginning), the close as duplicate is no longer valid. Oh, and the edit to remove the second question. –  Bob Jun 13 '12 at 11:13
    
Isn't what weird? This question is really unclear. Are you asking why dsl does not run at 100 Mbps when Ethernet can? –  psusi Jun 13 '12 at 18:48

1 Answer 1

There's a few practical reasons why your home internet is slower than wan. Firstly, the speed you can transmit data with diminishes with distance - the longer the distance, the weaker the signal gets, and the more interference occurs.

With home networking, you're talking of runs of tens of meters (common 100BASE-TX and 1000BASE-TX goes up to 100 meters). You're also serving a single system over this.

With a WAN you're looking a distances in kilometers, with bandwidth shared by many users.

With ADSL you're working with a limited part of the frequency spectrum (though adsl can go from 8 down, 1 up to 24 down 3.3 up) which slows it down.

Cable can go significantly faster, but most ISPs share bandwidth between users in an area.

You can also get gigabit or faster speed on fiberoptic links

At the end of the day though, it costs you maybe 10 dollars for that cat6 cable. Your ISP needs to dig up roads and lay much more expensive cable, and lots of it, so it makes sense for them to spread bandwidth out. That said, if you're willing to pay for it, there's no reason why you can't get lan-like speeds on a home or office internet connection

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So, WAN speeds are generally lower than LAN speeds because of distance and cost? –  Ozgun S Jun 13 '12 at 10:55
    
Distance, cost, and cause its invariably spread over many users. –  Journeyman Geek Jun 13 '12 at 10:55
    
last question, how is this possible to download large files on Mb level speeds so quickly? –  Ozgun S Jun 13 '12 at 11:05
    
If you want to download files faster, you get a plan that gives you more bandwidth? –  Journeyman Geek Jun 13 '12 at 11:07
    
@JourneymanGeek - It is not even about bandwidth per say. Its about the ISP unlocking and/or increasing your bandwidth limits. Everyone is connected to the same system, everyone in theory could have the same speed ( at equal distance ), there are different teirs because its a service ( and they can ). –  Ramhound Jun 13 '12 at 11:14

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