Help understanding download speeds

[ron ll]

I'm on Qwest DSL. The new Photoshop Beta download is a 1.8gb zip file. It wants to take 3hrs and 40mins to download yet someone else told me they downloaded it in about 15 minutes. I ran a speed test and it reports my d/l speed is 1.31 Mbps. Do I have a serious problem or is this somewhat normal?

[Norman Bernstein]

Lower than many cable internet connections, for sure. My Comcast connection is good for 7-8 Mbps, download. 1.31Mbps sounds more like DSL. If there is cable in your area, you might want to switch. Even 'aircards' (broadband mobile) are often faster.

[ron ll]

Lower than many cable internet connections, for sure. My Comcast connection is good for 7-8 Mbps, download. 1.31Mbps sounds more like DSL. If there is cable in your area, you might want to switch. Even 'aircards' (broadband mobile) are often faster.

Is your 7-8 Mbps what it tests or what your provider advertises? (I've found there can be a big difference).

[JBreeze]

You said you're on Qwest DSL.....I'm on Verizon DSL........

I've found that speeds seem to vary during the day, as well as varying by the source of the download.

I'd try the download this evening....the intertubes shouldn't be congested on a Friday night. If, after 5 minutes or so, the download isn't progressing at a reasonable rate, quit it and try again - that has also helped on occasion.

[ron ll]

Well, it pays to check for updates on the service. I just called Qwest and they say I am paying for 1.5mbps so a 1.3 download is reasonable. However, fiber optic is now available here and they have a package providing 12Mbps + free long distance for $1 less per month than I am paying now. The only setup charge is a new modem which is either $99 purchase or $5/ mo rental.

So folks, if you haven't checked with your provider recently, maybe worth a call.

[Nicholas Carey]

I'm on Qwest DSL. The new Photoshop Beta download is a 1.8gb zip file. It wants to take 3hrs and 40mins to download yet someone else told me they downloaded it in about 15 minutes. I ran a speed test and it reports my d/l speed is 1.31 Mbps. Do I have a serious problem or is this somewhat normal?

You most likely have RADSL via Quest/CenturyLink/whatever they call themselves these days. the "RA" bit means "rate adaptive." That means your speed and effective bandwidth gets dynamically adjusted (down) to compensate for line quality: a poor connection, or lot of noise on the line and you won't have much bandwidth.

Things that you can easily check:

0. Make sure everything plugged into your telephone line that isn't a DSL modem has a DSL filter between it and the phone line. This is absolutely essential. A DSL filter is a little dongle that looks something like this. It gets plugged into the phone jack and the phone/fax machine/other non-DSL modem device gets plugged into it:




1. Plug your computer in at the Network Interface box (should be a grey plastic box somewhere on the side of your house), where the phone line transitions from being Ma Bell's responsibility to being yours. If you get great download speeds there, the problem is likely in your wiring. If it's still sucky, you're pretty much SOL: the problem is in Ma Bell's court. You may have an old noisy line, or noisy mechanical switch. You may be a long, long way from the CO (DSL has a maximum run of 15,000 feet run as the cable flies between the CO and the subscriber's network interface).

Things to look for.

Are you running cat 5e or cat 5 cable (4 twisted pairs, 8 conductors total) from the network interface, or old-school 4 conductor phone wire?



Running old-school will hurt your bandwidth. It's non-twisted pair and that will result in a lot of noise and crosstalk. The reason etherNet supports such high speeds is that the twisted pairs make some sort of electrical engineer/electron magick happen so that doesn't occur.

You might consider pulling new Cat 5e or Cat 6 cable to replace the old 4-conductor stuff.

If you're pulling new cable or already have etherNet cable, make sure it's installed according to spec:

- No untwisted length should be longer than 1/2 inch.

- Minimum bend radius is 4x the cable diameter, c. 1 inch. Bends tighter than that or kinks in the cable cause signal loss and noise.

- Unshielded AC power lines (e.g., Romex) spew RF noise. If you're AC is in ground metal conduit or raceways, you're probably OK, but otherwise:

- Keep your cable as far away from AC wiring as possible (1 foot minimum).
- Don't run cable parallel to AC wiring
- If you have to cross AC wiring, cross at as close to a right angle as possible.

There's an argument to be made for running your cable in ground metal conduit to avoid possible AC interference (not really practical unless the walls are open).

[Norman Bernstein]

Is your 7-8 Mbps what it tests or what your provider advertises? (I've found there can be a big difference).

Test rate. It is faster than that, sometimes.

[Donn]

My cable speed is regularly 25-30K down and 5 up.

[Paul Pless]

I ran a speed test and it reports my d/l speed is 1.31 Mbps. Do I have a serious problem or is this somewhat normal?

Dude that's awful. That's like 3G cell phone speed. . .

[Norman Bernstein]

Running old-school will hurt your bandwidth. It's non-twisted pair and that will result in a lot of noise and crosstalk. The reason etherNet supports such high speeds is that the twisted pairs make some sort of electrical engineer/electron magick happen so that doesn't occur.

It's NOT crosstalk or noise... it's maintaining a constant characteristic impedance to prevent time domain reflections.

[BrianW]

It's NOT crosstalk or noise... it's maintaining a constant characteristic impedance to prevent time domain reflections.

That's the percocet talking.

[Norman Bernstein]

That's the percocet talking.

*lol*

Hey, even stoned, I'm STILL an electrical engineer!

[ron ll]

Thanks! Great info. BTW, this is my office, not home, so I'm stuck with what comes out of the wall. But next week it will be switched to fiber optic 12Mbps with a new modem. At that time I'll clean up all the interior wiring according to these suggestions and I should be good.

[Nicholas Carey]

It's NOT crosstalk or noise... it's maintaining a constant characteristic impedance to prevent time domain reflections.

That's why you're the EE and I just build software. that stuff makes my head hurt.

[Nicholas Carey]

Thanks! Great info. BTW, this is my office, not home, so I'm stuck with what comes out of the wall. But next week it will be switched to fiber optic 12Mbps with a new modem. At that time I'll clean up all the interior wiring according to these suggestions and I should be good.

If you pull new cable, pull Cat 6 instead of Cat 5e — the price differential is essentially nil. Fiber if you're feeling flush. Plan for the future, but remember, you're the last link in a long chain...and if you're doing wireless networking as the last link, the wireless link is the slowest — 802.11g ts at at c. 54megabits/sec on the physical (wire) layer (c.22 megabits/sec through put) whilst Cat6 cable is [theoretically] capable of up to 1 gigabit/second on the wire.

[BrianW]

If you pull new cable, pull Cat 6 instead of Cat 5e — the price differential is essentially nil. Fiber if you're feeling flush. Plan for the future, but remember, you're the last link in a long chain...and if you're doing wireless networking as the last link, the wireless link is the slowest — 802.11g ts at at c. 54megabits/sec on the physical (wire) layer (c.22 megabits/sec through put) whilst Cat6 cable is [theoretically] capable of up to 1 gigabit/second on the wire.

Once again, that's the percocet talking.

[Norman Bernstein]

That's why you're the EE and I just build software. that stuff makes my head hurt.

I fully understand. Software is what people do when they can't design circuits

[ron ll]

Followup:

They just finished upgrading my line to 12Mbps fiberoptic and I got the new modem hooked up and running. I'm now testing a strong 11 Mbps download with the same test that was previously showing 1.3 Mbps. And this added free long distance and reduced my bill by $1/month.

So I say again, if you haven't talked to your isp in a while, it might pay to check with them. They didn't tell me this was available until I asked.

[Nicholas Carey]

Followup:

They just finished upgrading my line to 12Mbps fiberoptic and I got the new modem hooked up and running. I'm now testing a strong 11 Mbps download with the same test that was previously showing 1.3 Mbps. And this added free long distance and reduced my bill by $1/month.

So I say again, if you haven't talked to your isp in a while, it might pay to check with them. They didn't tell me this was available until I asked.

Who's your ISP? We've been with SpeakEasy for years, but they've been bought by something called MegaPath and the quality of customer service has tanked...so we're looking to switch ISPs.

[ron ll]

Who's your ISP? We've been with SpeakEasy for years, but they've been bought by something called MegaPath and the quality of customer service has tanked...so we're looking to switch ISPs.

This is Qwest (Centurylink).