The toughest challenge in Internet connectivity today is that "Last Mile" from the ISP's Point-Of-Presence to the subscriber location.
They can run multi-gigabit fiber optic lines into your neighbourhood, but the last bit from their utility office or underground vault to your office/residence is the most difficult and that's where the cable modems and DSL modems come in.
This is, of course, notwithstanding those few lucky neighbourhoods where they have "fibre-to-the-home" service but that's rare.
The stated bandwidths are only between your ISP supplied terminal/modem to their router (a.k.a. "default gateway").
Beyond that there's all sorts of issues that network engineers have to deal with like congestion, packet loss, jitter, etc. across multiple router hops on the internet.
And this is notwithstanding traffic loads and bandwidth at the server at the other end.
Usually ISPs who run speed tester servers will have high bandwidth within their own network so if you subscribe to 25 mbps download you should contractually get that speed to the ISP's network but beyond that all bets are off, as they say.
I have a question regarding internet connection speed. Are the so-called "speed checks" rigged? I ask this because recently I received an email from CNET that contained a solicitation inviting you to check your connection speed. Well, I did and my result averaged around 6Mbps. My ISP is AT&T, which boasts its U-Verse is superior. I'm subscribed to their 12Mbps plan. So after I learned that the solicitation link clocked me at 6, I tested my connection on U-Verse's speed check which shows me clocked at around 12Mbps download and around 3 upload, which is fine but makes me wonder which is right? I've always kind of wondered what the actual speed is when at times I find myself waiting patiently staring at a screen as the page loads. Any thoughts or previous discussions on this subject? I'm wondering if speed is just a marketing scheme to entice one believing their connection is better than their competitor. And is there a trustworthy method of finding out my actual connection speed without bias? Thanks.
--Submitted by Alan L. of Columbus, Ohio

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