Wi-Fi connection and Bluetooth file transfer problems ( Android-to-WindowsXP )

[SergeyKostrov]

[ Updated on December 17th, 2012 ]

I have a Wi-Fi connection problem with an Android device. So, a Samsung Galaxy Tab 2.0 (7") could not connect to:
[cpp]
Security-Enabled Computer-to-Computer network ( over Wi-Fi )
Network Authentication: Open
Data Encryption: WEP
[/cpp]
Note: The device doesn't see that type of network!

However, it could connect to:
[cpp]
   Security-enabled wireless network
   Security-enabled wireless network (WPA)
   Security-enabled wireless network (WPA2)
   Unsecured wireless network
[/cpp]
Note: Verified in many places like cafees, airports, University of Calgary campus, etc.

Any ideas, tips or suggestions? Thank you in advance.

[ Summary as of December 17th, 2012 ]

A test with a MacBook ( Mac OS X v10.7.5 ) notebook was finally done and it successfully detected and connected to our Security-Enabled Computer-to-Computer network ( over Wi-Fi / Open / WEP ) created between several computers with Windows XP and Windows 7 OSs. The test was completed in less than 2 minutes without any issues and problems.

[ Summary as of December 4th, 2012 ]

- An update from Samsung for Android OS v4.0.4 ICS was recently installed on the tablet

- Wi-Fi Advanced Configuration Editor was installed on the tablet
  The application allows to see and edit advanced settings of a Wi-Fi network and it is
  downloaded from: market.android.com/details?id=org.marcus905.wifi.ace

- Linksys 'Compact Wireless-G USB Network' adapters are used on some desktop computers with Windows XP

- The following advanced settings of the 'Compact Wireless-G USB Network' adapter:

   NetworkType
   ShowHiddenSSID
   WEPKeyUse
   SmartScan
   IEEE80211H
   WirelessMode
   CountryRegion
   CountryRegionABand
   AutoChannelSelect
   Channel

   are considered as the most important and were modified many times during many tests

   Note 1: NetworkType is set to 802.11 Ad Hoc

   Note 2: Widest possible ranges for channels were selected:

   CountryRegion ( Country Region 11G ) - #5 Channel ( 1 - 14 )
   CountryRegionABand ( Country Region 11A ) - #7 Channel ( 36 - 165 )

- Microsoft Network Monitor v3.4 was used on some desktop computers with Windows XP

- A Wi-Fi Signal Strength is always 'Excellent'

- A workaround based on a Bluetooth connection was considered, it works and tested. However, a transmittion speed and a distance between tablets and computers are two significant constraints:

  A transmittion speed limitation of the Bluetooth connection - it takes too long to transmit large data files

  A distance limitation of the Bluetooth connection - a tablet could be away ( many meters ) from a computer with Windows platform
  Notes:
  - That computer could be considered as a 'Bluetooth Server'
  - Some number of Bluetooth adapters are also needed 

[Bernard]

Hi Sergey You have to download Microsoft NetMon utility ie. the first link http://msdn.microsoft.com/en-us/library/windows/hardware/hh451296 Please consult also NetMon blog : http://blogs.technet.com/b/netmon/ You can also consider downloading newer version of netmon "Message Analyzer" beta version.

[SergeyKostrov]

>>You have to download Microsoft NetMon utility ie. the first link http://msdn.microsoft.com/en-us/library/windows/hardware/hh451296 >>Please consult also NetMon blog : http://blogs.technet.com/b/netmon/ I see. Thank you.

[Bernard]

>>>...I see. Thank you...>>> No problem Sergey.Download also 802.11 standard it will be crucial in order to understand innerworkings of the wi-fi protocol stack.

[SergeyKostrov]

Hi Iliya, >>http://msdn.microsoft.com/en-us/library/windows/hardware/hh451296 >>... >>...1.Download and install NetMon.exe... >>...2.Download and install the Windows Driver Kit... Should I install the Windows Driver Kit? That looks as too big dependency and I really don't want to do it.

[Bernard]

...>>>Should I install the Windows Driver Kit? That looks as too big dependency and I really don't want to do it...>>> Definitaly NO!! Do not install Windows Driver Kit because there is no such a need and dependency.NetMon will operate smoothly without WDK. I would also suggest trying to set ad-hoc connection between two windows machines.This could remove the responsibility for the connection failure from the windows OS.

[SergeyKostrov]

>>...NetMon will operate smoothly without WDK. This is what I wanted to confirm. >>...I would also suggest trying to set ad-hoc connection between two windows machines... I remember that it was set long time ago but I'll verify.

[Bernard]

Hi Sergey I know this is not related to this thread,but I could not resist to post it.I have Finally solved the problem of loss of an accuracy when writing various trigo function implemented as a BigDecimal types.The culprit was was bug in even factorial calculation:) Now I can calculate with a precision reaching more than 1000 decimal places.It is more interesting that Horner scheme produced the wrong results when compared to the iterative method.

[SergeyKostrov]

Hi Iliya, Just one question: >>...It is more interesting that Horner scheme produced the wrong results when compared to the iterative method. What iterative method do you mean?

[Bernard]

>>...It is more interesting that Horner scheme produced the wrong results when compared to the iterative method.>>> By iterative method I mean coefficients computation which is based on the for-loop iteration.Albeit slower than coefficient pre-calculation and Horner scheme summation,but in the case of Java BigDecimal types iterative computation was able to produce the correct result almost up to PI/2. I suppose that methods(add().multiply()) "tethering" could be blamed for the loss of precision(polluted by the rounding error propagation).

[SergeyKostrov]

>>...slower than coefficient pre-calculation and Horner scheme summation... Some compromises almost always need to be done.

[Bernard]

>>>...Some compromises almost always need to be done.>>. Yes I know ,but in the case of object types arithmetics both choices are bad.

[SergeyKostrov]

Hi Iliya, >>...The culprit was was bug in even factorial calculation:) Now I can calculate with a precision reaching more than 1000 decimal places... Would you be able to create a new thread on "Android" or "Software Optimizations" forum? You're doing a very interesting R&D and it will be very good to share as much as possible details. Best regards, Sergey

[SergeyKostrov]

Hi Iliya, This is a very small update regarding Android-to-WinXP Wi-Fi problem. I've installed Microsoft NetMon v3.4 and spent some time today ( it is a really good tool! ). No success so far and I provide more technical details by the end of this week ( or over weekend ). Best regards, Sergey

[Bernard]

...>>>No success so far and I provide more technical details by the end of this week ( or over weekend )...>>> Did you try to capture and interpret 802.11 protocol's frames? I hope that problem is not buried deep inside WinXp protocol stack,because debugging network drivers on retail Windows release is very painful, checked build should be used instead. Did you try to connect your galaxy tablet to Win 7 pc?

[Bernard]

...>>>Would you be able to create a new thread on "Android" or "Software Optimizations" forum...>>> Can I create thread which is dealing solely with the Java code on the Software optimization forum? How many developers on those forums are coding in Java? If you are interested in testing I can send you a source files of large precision methods?

[SergeyKostrov]

Hi Iliya, >>Can I create thread which is dealing solely with the Java code on the Software optimization forum? ... I think Yes but it can be moved by a moderator to 'Android applications on Intel architecture' forum. >>How many developers on those forums are coding in Java? ... I have no idea but I think that on Adnroid related forum there are many users that do programming with Java. >>If you are interested in testing I can send you a source files of large precision methods? ... I would be glad to participate in discussions related to that subject. Sorry, too busy with different technical issues. Best regards, Sergey

[Bernard]

...>>> I think Yes but it can be moved by a moderator to 'Android applications on Intel architecture' forum.>>> I'm afraid of this and I think that i will create such a thread on Oracle Java forums. Do you know some very technical numerical methods and/or scientific calculation forums?

[SergeyKostrov]

>>...Do you know some very technical numerical methods and/or scientific calculation forums? No. I think Mathlab forums could be very 'scientific calculation' oriented but guys on these forums do not use Java.

[SergeyKostrov]

>>...We have some progress with a Bluetooth connection but Bluetooth Transfer Wizard on a Desktop computer still can't transfer >>a file to the tablet. That workaround finally works! - There are strange timeouts when a file is sent from Android tablet to Windows XP. In total it takes ~1.5 - 2 minutes (!) to transfer ~140KB file. - There are NO any timeouts when a file is sent from Windows XP to Android tablet. In total it takes ~10 seconds to transfer ~140KB file. However, there is some instability with that workaround, for example, after 10 transfers it stops working. Android tablet and a desktop computer with Windows XP have to be rebooted to restore Bluetooth software subsystems to normal / working state.

[Bernard]

>>> There are strange timeouts when a file is sent from Android tablet to Windows XP. In total it takes ~1.5 - 2 minutes (!) to transfer ~140KB file. - There are NO any timeouts when a file is sent from Windows XP to Android tablet. In total it takes ~10 seconds to transfer ~140KB file.>>> Sadly I have never "sniffed" Bluetooth network connection.I t can be done with the help of Wireshark and Bluetooth protocol stack is simplier than wi-fi stack. The most frightening thing is some failure of software/hardware interoparetibility and/or interaction in your Android tablet.In order to eliminate this try to send files by Bluetooth to Win7 machine or send files between two Android devices. My question is Do you want to resolve Bluetooth related problems first or concentrate or wi-fi connection? >>> There are strange timeouts when a file is sent from Android tablet to Windows XP. In total it takes ~1.5 - 2 minutes (!) to transfer ~140KB file.>>> In this case each packet have to be parsed and its fields interpreted.Such a behaviour can be due to some transmitting buffer filling up inconsistency ,but I said earlier in my post we have to see the live connection packets first.

[Bernard]

>>> There are strange timeouts when a file is sent from Android tablet to Windows XP. In total it takes ~1.5 - 2 minutes (!) to transfer ~140KB file. - There are NO any timeouts when a file is sent from Windows XP to Android tablet. In total it takes ~10 seconds to transfer ~140KB file.>>> Sadly I have never "sniffed" Bluetooth network connection.I t can be done with the help of Wireshark and Bluetooth protocol stack is simplier than wi-fi stack. The most frightening thing is some failure of software/hardware interoparetibility and/or interaction in your Android tablet.In order to eliminate this try to send files by Bluetooth to Win7 machine or send files between two Android devices. My question is Do you want to resolve Bluetooth related problems first or concentrate or wi-fi connection? >>> There are strange timeouts when a file is sent from Android tablet to Windows XP. In total it takes ~1.5 - 2 minutes (!) to transfer ~140KB file.>>> In this case each packet have to be parsed and its fields interpreted.Such a behaviour can be due to some transmitting buffer filling up inconsistency ,but as I said earlier in my post we have to see the live connection packets first.