RMcQ

Why are there three files downloaded before the main file? I thought I read about this somewhere on the site but can't find it again.  Thanks.

16 hours ago, nanobot said:

If you're 2.5 miles from the "home office" (typically an MDF/IDF - main / intermediary data facility), you are outside the "sweet-zone" of ADSL.

Typically, (A)DSL sees maximum throughput at 2 miles or less from a MDF/IDF. Basically, the distance between your demarcation point (modem) and your ISP's closet.

You're only half-a-mile outside the sweet-zone, so I would still expect you to see reasonable speeds. That said, you might never see a stable 6Mbps, due to ADSL typically using older, buried phone / Cat3 lines. (Unless CenturyLink ran shielded coax/twinax copper or fiber, which I highly, highly doubt.)

 

The burst you see with TMN is likely because the lines are cool, so there's no electromagnetic field around them. Because ADSL is typically Cat3, it's often minimally (if at all) twisted, unshielded, and poor-cabling, so it's easy for the cabling to build an electromagnetic field that interferes with signal transmission. This field won't exist at an idle, it will only exist when data is being transmitted. Once the field has built up (often as quick as 50-2500ns) it starts creating cross-talk and signaling interference, slowing the throughput you can achieve. (Basically, error-rates go up, and as a result more of your bandwidth is spent on handling those errors.)

Thank you for your explanation. It certainly describes what I am seeing and the possible reasons why. When DSL was first made available at my address they offed three packages; 3/6/10Mbps. 10Mbps is no longer offered. Centurylink customer service keeps saying I should NOT expect to see what I'm paying for due to routing issues which they cannot control, the age of the infrastructure and that I'm very close to the speed that I'm paying for consistently. Then they say upgrades are coming for my area in 2020.

If I go into the modem it reports the "DSL signal" that it is seeing. Currently it is 5.8Mbps. I saw 7Mbps once but it's almost always 5.8 and I don't know how often the modem refreshes itself to report the current signal.

My original question was to see if I could find out how the speeds are set by Centurylink or any other provider on a customer by customer basis. Now that I have more knowledge regarding this I probably shouldn't be complaining. People that get far less than what they pay for are on more solid ground complaining about it.

Thanks again!

5 hours ago, rebrecs said:

What kind of router do you use ?

 

Westell A90-750022-07 ADSL2+.  It's a 4 port Ethernet/wireless. I have both computers connected by Ethernet. Been using it for years and have the manual in PDF format.  I get the same test results when using wireless, firewalls on or off and making sure nothing else is trying to grab some bandwidth while running a speed test.

rebrecs, Centurylink uses Ookla. It looks like they connect me to a server in Kansas City, Mo. to run the speed check which is only 45 miles away. The upload/download results are very close to TMN's but nowhere near as informative. I don't see a spike at the beginning of the downloads by just looking at the speed dial and I don't know what the 2ms "jitter" is that Ookla reports.

12 hours ago, rebrecs said:

Interesting question. There are several ways to do it. Each has less or more merit depending on the goal. Given that an ISP's goal is the  managing speed limits on a per customer basis, and the fact they tend to discuss (and sell) "speed" in terms of bits-per-second, my guess would be they are throttling at the signalling level versus measuring and capping a "byte flow" inside their switching gear. If I am right about that (and that's a big if) then the modem at their end, that your modem talks to, would set the max transmission speed.

I really don't think it would be practical for them to do otherwise.

That's my $0.02

 

 

Throttling at the "signalling level" as you suggest seems to be a pretty good guess going by the graph that I attached.  This is typical of what I get. I just wish they would throttle at what I'm paying for.  It's like buying something that costs $9.50 total, giving them $10.00 and not getting my change back.

I have only recently discovered TestMy.net. It's a fantastic service that's being provided and has explained my irritation with Centurylink over the years. It is only recently that the service has become stable where I live (west central Missouri) so I guess they're doing something to improve with the exception of providing faster speeds.  Every Mbps counts in a rural setting.

I'm with Centurylink that sells me 6Mbps ADSL broadband. They say that is all they can provide since I am rural (only 2.5 miles from the central office).  My question is how do they cap the limit by subscriber? I consistently get only 5 out of the 6Mbps that I pay for.

Recently their service messed up and Centurylink was briefly giving me an erratic 12-22Mbps download speed so I don't think the old copper lines are an issue. I'm also using the Westell 7500 modem that they gave me years ago. Would the old modem be stealing some speed and keeping me from the 6 that I pay for? How is the speed limit capped? Mechanical? Software?

I'm mainly interested in how the speeds are capped.  Thanks...