Anon |  Can anyone answer this?(ADSL download speed)
I have bellsouth adsl and I am overall pleased.My question is: I have tried several download test sites and they all average about 1.1Mbps which to me rocks.I have used the tweakster and all is good.I know the differance between a bit and a byte.So why no matter where I go or what I download the fasted I can reach is 150kbps?If the sites or people(direct connect,kazaa,edonkey,napster....)are limiting there upload speed why worry about upper level broadband? Forgive me if the answer is painfully stupid I just cant figure it out.
Thanks everyone,
Scott - badride5@hotmail.com |
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AR
Premium,ExMod 2001-04
join:2000-09-21
Toronto, ON
 ·Rogers Hi-Speed
| Hi! Welcome to DSLR.
150kbps = 1200K
1200K/1536K * 100 = 78%
You could go a little more but if you get 80-90% of your advertised speed, there is not much you can do to go past that. Maybe I missed this, but did you try out the tweaks forum here on DSLR? |
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Anon |  Thank you araina.
How do you come up with that formula?
I am not doubting you only curious.
No I have not been to the tweaks forum I will check it out now.
Thanks for your reply |
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tschmidt
Premium,MVM
join:2000-11-12
Milford, NH
 ·Hollis Hosting
 ·Verizon Online DSL
·Fairpoint Communic..
| reply to Anon
When you say your download is 150kbp/s, that is 150 k bits per second. If you are getting that number from the download dialog box in Windows the number is reported in bytes. If your connect speed is 1.1Mbp/s the fastest you can download is 137.5KBp/s or 138 Kilobytes per second.
1.1Mbp/s is the raw data rate of your connection. Communication protocols add additional data reducing speed. A good rule of thumb is that communication overhead is about 20% thus reducing useful thruput to about 110KBp/s.
An easy way to do this in your head is to divide communication speed by 10. This converts bits to bytes and factors in the 20% overhead. |
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Anon |  WOW,tschmidt
Thats very usefull info.
Thank you very much for your response.
I love this place,you all rock. |
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bandizar
join:2001-06-20
Brea, CA
| Hey, Araina! Thanks for your help earlier. Chugging along at 1290 now! =)
Back to the thread. PPPoE overhead can be as little as 3%..the real bandwidth killer is ATM. All of your PPP traffic is encapsulated in ATM cells (the underlying transport). As I understand it, ATM cells have a 48 byte payload and a 5 byte header....thus 9.4% of your bandwidth (or so) is eaten up by those pesky 5 byte ATM headers. |
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rbarbier
join:2001-06-11
Perris, CA
| My speed test are 1400/385. I download at 179. I am on ATM. I think this is good. I have done other speed tests also and get around 1.39 MB/sec. Maybe I am just lucky. I only am paying for 1.5/128 also  . I am using NEN with DSL Extreme. |
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vkr
ExMod 2001-06
join:2001-04-03
Terra
| reply to Anon
said by badride5:
So why no matter where I go or what I download the fasted I can reach is 150kbps?
Are we talking bits, or Bytes?
There's a big difference between a small b and a big B.
When you in Netscape, IE, or most other utilities, they rate your throughput in KiloBytes. (K/s KB/s)
The lines are rated in bits and 8 bits make a Byte. Take the line kbps rating divide by 8 to get KB/s throughput.
A line rated at 384kbps (kilobits per second) is the same as (384/8)= 48 kBps (KiloBytes per second) and you'll get about 85% percent of that, accounting for loss and overhead for a total of 40.8 KB/s (KiloBytes per second).
If you getting 1.1Mbps (Megabits per second) throughput, is the same as 150 KB/s (KiloBytes per second), which means you sync'ing up around 1408 kbps (kilobits per second).
((1408/8)-15%)=149.6 KiloBytes per second
vkross
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If I'm not here, then I'm somewhere else.
or
Will work for DSL! |
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