confused download speeds

[topsy99]

I have a connection on wireless that speed shows a download speed of 25 MBS

I have another that is adsl2 and has a download speed of 18 mbs

when I download a long file on wireless it takes 5 times as long as the adsl 2

wonder why that is?

[Geek-9pm]

Are you talking about
-  download speed over the Internet
OR
- download speed over you local network.

Internet speed is  seldom over 10 mega bits per second.
Local wireless network is often 54 mega bits per second.

[soybean]

Internet speed is  seldom over 10 mega bits per second.

  Many ISPs, both cable services and DSL, offer speeds exceeding 10Mbps.

[strollin]

Maybe just a typo on your part but 25MBS indicates 25 megaBYTES per second while 18mbs indicates 18 megaBITS per second.  There are 8 bits to a byte so if the speeds are actually as written the speed difference would be more than 8 times slower.  Upper case B indicates bytes, lower case b indicates bits.

Some places show speeds as MB, some as Mb while others use KB or Kb.  It can be confusing to attempt to match one speed measurement with another.

[Geek-9pm]

For reference; in asynchronous serial communication it take 10 bits to make a byte of 8 data bits. In synchronous serial  it comes close to 8 bits. About 8.3 bits.

[camerongray]

For reference; in asynchronous serial communication it take 10 bits to make a byte of 8 data bits. In synchronous serial  it comes close to 8 bits. About 8.3 bits.

How is that relevant?  And how on earth do you get fractions of a bit?

[BC_Programmer]

Maybe just a typo on your part but 25MBS indicates 25 megaBYTES per second while 18mbs indicates 18 megaBITS per second.
There are 8 bits to a byte so if the speeds are actually as written the speed difference would be more than 8 times slower.  Upper case B indicates bytes, lower case b indicates bits.
Some places show speeds as MB, some as Mb while others use KB or Kb.  It can be confusing to attempt to match one speed measurement with another.

Uppercase M is mega. lowercase m is milli. Vector units (X per Y) use a slash. according to the 2008 ISO/IEC standard, Megabits per second would be "Mbit/s".

For reference; in asynchronous serial communication it take 10 bits to make a byte of 8 data bits. In synchronous serial  it comes close to 8 bits. About 8.3 bits.

10-bit character frames are only used by RS-232/Serial ports. Unless you are using an ancient modem for dial-up it is quite unrelated to the topic of Internet Connectivity. I do wonder what "synchronous serial" you refer to, since PCs do not support synchronous transfer via Serial Ports.

[topsy99]

I type How fast is my internet? into Ookla and those are the answers I get.  I see both the wireless and ADSL2 as giving comparable readings.   e.g. 25   wireless and 18 adsl2.    so assuming they are both the same type of speed  the wireless takes at least 5 times longer   8 times could very easily be right.

In Australia we have just sacked a lunatic government who was trying to give us all 100mbs at our house.   according to this it is a hoax.  the wireless at 25mbs is part of this roll out.   But it takes 5 to 8 times longer to download a documentary film on wireless than on adsl2.   is the faster speed of wireless a hoax.?

[Geek-9pm]

Yes, it is a hoax.  But somehow they can defend the pretense. Both wised and wireless connections can use different kinds of modulation methods. To be honest, the Telecom firms  should use terminology that is comparable.
Some system use timer division multiplex. An alternative method assigns speed as needed. I is hard to measure the real speed of these desperate methods. Anyway, its beyond the scope  of this topic to get into all the stuff the Telecom guys use.

A reference for TDM:
http://en.wikipedia.org/wiki/Time-division_multiplexing
If you want more:
http://www.daenotes.com/electronics/communication-system/multiplexing
Some theory with the math:
http://w3.gazi.edu.tr/~ertug/ee437_labhandout.pdf
An it goes on...
Brief summary. The Big  Guys will use a system that gets them high profits  and  letting the customers  think they got the best deal. One factor is the  US Patents on TDM, so they have to come up with something that looks different.
So you have to make your own tests and ignore what they tell you.

[topsy99]

worked it out. Sorry to waste people time but lack of knowledge causes my silly questions.  I was downloading a documentary and it was taking about 40 minutes on my windows 7 64 bit whilst on my vista machine it takes about 4 on 32 bit. Have checked the downloader out and it is not designed to be used on 64 bit. It actually works on 64 bit but much slower. I don't understand that either nor why they make an embedded downloader for 32 bit only when the world is now 64 bit.

I downloaded the same documentary on xp nec 12 year old 32 bit laptop and it took 4 minutes.

sorry to waste your time but have solved the problem.

[Quantos]

LOL, glad to hear that you got it sorted out.

[Geek-9pm]

topsy99,
Thank you for a very interesting post.

[topsy99]

problem is back. apparently windows 7 doesn't work with the new NBN   they said if I pay Telstra they will visit my home and fix it.  sounds shonky to me.
any ideas.

[BC_Programmer]

problem is back. apparently windows 7 doesn't work with the new NBN   they said if I pay Telstra they will visit my home and fix it.  sounds shonky to me.
any ideas.

You're 100% right to be skeptical of their claim, because the Operating System on a PC has practically nothing to do with it's capability to get access to the Internet. And it would certainly not intrinsically explain why you are getting slower speeds.

Is this the same set of machines? what is the "downloader software" you mentioned previously?

[Geek-9pm]

For what it is worth.
An objective test could be done with:

• Two PCs with different OS; labeled A and B.
• Two different download sites; labeled C and D.

Then perform repeated tests for
A on C, A on D
B on C, B on D
After N iterations, compute mean and divination.
Yes, time consuming, but more reliable that guesswork.
General reference:
http://en.wikipedia.org/wiki/Bandwidth_throttling

Bandwidth throttling is the intentional slowing of internet service by an internet service provider. It is a reactive measure employed in communication networks in an apparent attempt to regulate network traffic and minimize bandwidth congestion.

[topsy99]

some sites seem to behave differently.  I us GOM Picker as a downloader   I have now switched to 4k   and it downloads reasonably well on windows 7.    but alternately when downloading a program update or a video from SBS on Demand (Free to public)  it takes forever. Maybe this is an issue with the provider of the video.   Regarding separate computer tests   NEC (old laptop) xp GOM PIcker works fine.  ALso on Vista adsl 2 works fine.  on windows 7 (same connection wireless) as the NEC takes ages.  e.g. 10 times longer than xp and vistA.    the  4k downloader is a little slower than GOM Picker but works on windows 7. So probably the downloader. I cant explain why shareware and other items take so long.  For some reason I had a thought that NBN Wireless 25mbs would be faster in all cases but it isn't.   

[topsy99]

Righto.   Comparison.



64 bit. internet explorer   .   file youtube 33 megabytes.          30%  and two minutes start.
32 bit  internet exploer         same file                                    finished.  e.g. around 6 minutes.

this suggests around 24 minutes for 64 bit internet explorer    and 6 minutes for 32 bit downloading the same file.