Tuesday, February 12, 2013

iPhone 5 и сеть и батарейка

Недавно, я все таки решил выкинуть свой VDSL/WiFi modem/router (модель говорить пока не хочется, многие ее могут использовать до сих пор, 
это была первая модель на рынке с поддержкой VDSL/50+Mbit/s)

И если оригинальный, прежний роутер поддерживал WiFi 2.4GHz и 5GHz то фактически, у него была одна антенна и поэтому приходилось выбирать что то из предложенного, но не оба диапазона сразу.
Что не могло особо нравиться в силу живого "зоопарка" разных устройств, которые выкидывать пока что не планируеться.

Вообщем, новое приобретение поддерживает и VDSL (отлично) плюс WiFi стандарты, НО у него две антенны ( можно сделать и два WiFi SSIDs ) - поэтому 2.4GHz и 5GHz поддерживаем одновременно.

Что характерно, мой iPhone5 теперь уверенно сидит на 5GHz и более того, его батарейка (iOS6.1 на данный момент) несколько "пришла в себя" и начала показывать вменяемые расходы.

А теперь о главном, IMHO Apple подсознательно ориентировала iPhone5 для использования в новых WiFi сетях и стандартах,
если у пользователя существующее WiFi оборудование и может быть старое - имеется шанс получить проблемы, когда iPhone5 будет активно "восстанавливать" сеть, дабы она была, но этим же - активно садить батарейку.

В итоге - такая большая путаница в вопросах/ответах/пуллах голосованиях вроде:
- ест ли ваш телефон батарейку больше?
(ибо часть людей уже на новых WiFi routers, 3G/LTE etc )

Вывод: решение будет только индивидуальным.

- я не знаю, стоит ли говорить пользователям всегда и открыто что то вроде: для нашего апарата, лучше всего избавиться от старого железа в виде роутеров, которые новые протоколы не поддерживают. Или : Ваш провайдер использует "некоторые ньюансы 3G/LTE стандартов" и поэтому....

- я не особо хочу включать reversing mode и смотреть все тех. логи роутера, systemlogs of iOS etc. Reversing mode is OFF

- Apple это просто то, куда и меня сейчас дотянулись руки, но глаза уже видят похожее с другими именами...

Tuesday, January 8, 2013

processor cooling, fun in office ...

As we have to know , processors and CPUs these days during its normal work inclined to get hot, sometime very hot, therefore and to do not overburn itself,
processor die is cooled by some kind of heat sink.
If heat sink does help for some reason , CPU will throttle itself by decreasing working frequency, 
this normally takes some time.

So, recently, we've got a bulk of brand new HW, very brand new. 
Starting of the first system was a bit disappointing - show some weird BIOS issue and nothing more, even initial BIOS doesnt not come up.
Second system - the same, just shown issue is different.
Third....Fourth ....
Fifth - was starting just fine ! But only twice, thirds time and any after - nothing.

After checking on "this and that", decided to replace used thermal paste 
(used one was so bad and was looking more like a used chewing gum from the quality)

and .... it helped !
Story is not about us being smart enough thought...

Using of the proper paste and initially - would save not only my time but others, 
besides and pricewise - it might be like 1 USD on top for 100 systems.

Second story I was told - there is a guy (now - seriously) who is not sure if we are officially allowed to replace this paste and it might change benchmark results.
(We are using very good thermal paste, have no doubts )

So, now, in the office, we are looking for the person, who would officially allow such paste replacement...

Sunday, January 6, 2013

safe platform for banking?

These days banking and mobile banking is a default service of most banks, very convenient service.
However, if you would like to do it safe and secure what platform or PC would you take?

That is the question where for now - there is a simple answer: non-jailbreaked(iOS) OR non-rooted(Android) mobile device.

Think: if on PC or Mac or jailbreaked/rooted mobile device - you can have some form of malware or spyware which you even is not aware of, 
original iOS or (maybe) Android platform is an exception, up to now, nothing can log your keyboard typing, make remote screenshots etc.

Well,it is so good that for jailbreaking you need to do some and particular dedicated steps and only - if you need to.

Sunday, September 2, 2012

Android and boot animation

Just wanted to check how such fancy view been created for Android 4x , Ice Cream Sandwich or ICS:

Quick investigations shown that general boot process for Android-based devices looks like this : linux:boot:android

Just notice such step as:
bootanimationShows the animation during boot-up
ok, after short lookup in the source, I could find one important file, like BootAnimation.cpp

You can see all details inside but in fact - not much OpenGL ES been used, beside showing textures over time as animation frames, see bool BootAnimation::threadLoop()
from the link above.

OpenGL ES usage is mostly all about following calls:
with doing animation sequence itself inside bool BootAnimation::movie()
with even more simple calls.

Sad story, I was under impression that boot animation is dynamic in the full sense and rendered by OpenGL ES 

... well, just was a hope ...

Besides, you can see where animation located and now it will be easy to replace for the own one, if you would wish..

example of the bootanimation.zip is here: http://www.mediafire.com/?663k1abf2d1wy2m
or just google for such raw sample for your best look...

( you can replace default with yours with adb command like:
adb push ./bootanimation.zip /data/local/bootanimation.zip 

see in sources - User's boot animation has higher priority vs system's one,
unless encrypted system is used AND present )

Is my mobile emailing secure?

Just wanted to really check if my emails from my iphone usage can be sniffed meaning be visible to someone if I would use some WiFi hotspot, 
like when traveling...

In order to check this, had to establish my small test environment, like very good described here: Capturing iPhone traffic with Wireshark

Now different techniques possible but I wanted to do it fast, lazy me...

So I opened captured with Wireshark packages and searched for "yahoo" and "google" as email services I am using:

Now about findings:
- For yahoo , I see certificate exchange and more:

- For gmail, also:

and sadly ( joking ) - nothing unencrypted/unsecured about my email text, email contacts etc

Well, feel myself safe , 
or ?

PS: nothing especially been made for default email settings,

However, for gmail account: "Using of SSL" set to ON,
Yahoo mail on iphone currently has no such setting.

Sunday, June 3, 2012

Video decode on CPU vs HW / iOS and battery

Just had a fun to look deep at some video stream app on iOS devices, it is a nice app as it allows to play variety of video stream and not only "supported by Apple" ones (meaning hardware/HW/GPU way of video decode and playback)

Under the hood: it uses VLC parts and bits together with the trick as:
- decode on CPU (arm) / via standard VLC code
- video output via OpenGL stack / iOS SDK

This approach allows to use AirPlay also and quite handy
even thought with some setup limitations:
like you cannot establish a proper connection (called "Mirroring") from withing the app but on the system level (yet restricted by Apple down to the Private API, where such usage will make the app not acceptable for AppStore-based distribution )

where in general: You can add an AirPlay picker to your media playback controls by using MPVolumeView...

And the last note: I have a strong feeling that such approach drain my battery like 2-4x times faster, if I would compare it to iOS default or presumably HW based video playback.

Not sure if I really like it.