Tuesday, 2 November 2010

Android LG GT540 - 4 Days Log

Well I need to write this because finally I arrived in 2010. My wife given me as a birthday gift a new android phone, which I deliberately chosen to be the cheapest one in market. She got me an LG GT 540 Optimus for less than £100. The choice was deliberate because I wanted not to have any mercy or guilt in hacking it to the bones.

Well until now I already updated it to android 2.1 (originally it is a 1.6 phone), rooted it, moved all the application to the SD card and increased the memory to run apps by putting some swap space in the SD card. Definitely having a Linux on your pocket gives you freedom as you would never imagine.

In the next days I will be posting details on how I did all these things and the advantages of having done such things. I will start posting as soon as my new SD card arrives, since I need more space for doing things.

Monday, 23 November 2009

DoubleTwist - Putting media to your Nokia Mobile made easy (MAC)

Some days agora I came across with a software called doubletwist. It had the odd promise of making media transfer easy to nokia mobiles. It is something I have been trying for ages using all sort of suit and tools. None worked as smoothly as doubletwist.

It has been a very big handycap for me, since I sold my iTouch ( for beliefs agains Apple attitudes ), to have with me my media and being able to use it around my day-by-day. Doubletwist is so cool, that it imported even my play lists from itunes, and now I can also buy DRM free , cheap music from amazon, as well as importing everything (DRM free) from my itunes. It handles also the codec conversion, that was so painful before.

So, if you want to get rid from the evil of Apple controlling your mind and making you mad about the "brand new feature" that every single sensible player had since 2001 or by predating nice features just because it "may harm their business", this is a very nice option. The only problem is that it run just on Mac OS. Can be a nice try if you are like me, trying to phase out Apple from your life, but you can't just throw in the bin the £1000+ laptop you bought 2 years ago.

Monday, 15 June 2009

Watching international TV on your Xbox/not 360

This post is to celebrate my success into putting Justin.tv completely working on my Xbox. In fact I'm not using a plain Xbox, but a modified version using Xbox media Center.

Since May 2009, the Xbox media Center SVN version supports playing generic flash videos, and with that a lot of nice websites.

I want to draw attention to the fact that Justin.tv broadcast as lot of live channels from a lot of different countries and gives a very nice opportunity for those who live abroad. For example, yesterday night I was watching the most hated TV show in Brazilian Sunday afternoon live from my coach in Cambridge.

All this support is a straightforward. Once you have Xbox media Center installed on your Xbox you just need to install a plug-in. This is done with a couple of clicks using your remote or Xbox controller.

FlixWagon - Mobile phone live Broadcasting

I have been looking for a nice application to broadcast live with my Nokia mobile. In fact, I was looking something just like as Justin.TV.


I came across to Flixwagon. FlixWagon is a software for you to install on your Nokia mobile that enables you to record live videos and automatically upload to a youtbe like website. This website has some much better features that include video editing and video downloads. it also supports some interesting features such as chatting and tagging directly from the mobile. Very cool for broadcasting live from conferences. I expect to use it in the next one I attend.

Here is a test I did in my own office using my Nokia mobile:




The website for you to download is http://flixwagon.com/. This broadcast costed nothing since I was using the WiFi network within the building.

Tuesday, 24 March 2009

Spam - How to fight back?

Well during the last couple months I have seen a lot of the efforts about tackling genuine spam e-mail (not including malware) to be as palliative as possible. Basically, what we have been doing in the last years is just trying to conceive a way to discard what is just unsolicited commercial e-mail, not concentrating on the economics of the business.


I have been thinking lately abut it, and what makes spam so compelling is its cost (actually this is not a new idea). It basically means that you do spam because it is cheap, direct and people just try to get rid of it, nobody actually fight back.

When I mean fight back is to take down the spammer by any mean, from the plain and ethical legal process of cancelling the domain name to a raw, and mundane DDoS. If yo are faint of heart or you believe in ethics as the only way to solve the issue, I recommend you to stop reading.

OK, here comes my idea: Lets attack the spammer where it really hurts. Lets change a bit the economics of the matter. If spamming costs more, than maybe some people will not use it as a marketing tool. I mean specially those specialised companies on "direct internet marketing" will start to have bigger operational costs, making them less profitable and thus increasing the costs to the company hiring the marketing tool.

My idea can easily be implemented with today's available technology. I mean that, if we are able to build an e-mail client extension where the user can signal when something is or not actually a spam, we could basically set up some rule to poke the server where an embedded image (in the spam) is coming from, or even an URL present in the e-mail on a regular timely basis.

The interface should be easy to use, just asking how angry the person is that day with spam, and from that derive the counter-attack strategy (poking rates). After that, we can run in a mode where the user can say what is spam and what is not (safer mode) or even let any tool that detects spam heuristically do the job.

The idea behind this is that when a marketing company sends an e-mail, they take into account that no more than 10% will actually receive the e-mail(our strategy is discard), and from that less than 1% (from the total) will actually open it. With our extension, we will increase the spammer's server load poking him for everything that is "pokeable" in the message. We can do it repeatedly, lets say 10 times a minute. This means that his cost with bandwidth and servers will increase without increasing the actual return for the number of spams sent. So we are attacking the economics of the game.

Of course no idea is perfect, and I can see at least two initial drawbacks to the idea: First we as we know spammers will adapt putting less "pokeable" content in their messages. There will be no URLs, no images and no return e-mails. This means two things: or the spam will come with everything already embedded in it, thus costing more server time and bandwidth to send it, or it will less appalling to someone to buy anything, since they will loose a lot of the marketing power by not being able to use the above mentioned things.

The second drawback is a bit more (ethically) discussable. Imagine that someone just hires a "direct marketing" to take down some other's website. Well as we know this is a possibility, and will actually affect more the smaller players in the Internet game. But I think this is a worth causality to a greater good (like in any war), since that when the spammers hit someone and take them down or increase the cost of their business, for sure there will be legal cases against the spammers. If they hit some one bigger the bigger will be the case.

Even though ethically questionable, this idea, I think, is one way for an individual to fight back the spam industry. What we can do is unite power and spend some Kb of data each to increase the spammer costs, changing the dynamics of what is happening. Transferring the fight to another niche and making the whole business model less profitable is for sure much more efficient than most methods we have seen so far.

What do you think? leave comment in the blog.

Thursday, 12 March 2009

Dim Dim - Video Conferencing


I have been searching for good solutions on web-meeting tools for a while. My main objective is to setup a remote training grounds, where I could give some training to people remotely and also keep this for posterity. Almost all the good ones are not free, and the 100% free one just stink.

I was looking for a solution that would be ideal for webcasts and also for teaching purposes. So it should include some VoIP (voice communication), a white board mechanism e also screen sharing.

Skype running on the Mac is a good solution (100% free), but it lacks some of the (free) features I would like, and one is the recording of the conference. Actually its screen sharing is really handy, and I can not understand why it is not available in Windows for the main stream.

Well, after a lot of research I came across this site:

http://www.dimdim.com

Dim Dim is a (most) free solution that has everything I need. Indeed it covers all my requirements, and is free for what I want (less that 20 users). It is a really cool solution that mostly run on adobe flash, and gives you all the functionality needed for a proper teaching session online. These include, a white board, a chat, a camera for the teacher, voice, and screen sharing. All this allied to the possibility of recording everything and download it in .flv, thus enabling you to create your own lectures library.

I will test my main idea next term, trying to put a supervision group to work over this solution.

And now ITV catch up and Films

Since my last post on the BBC iPlayer I have been looking for other plug-ins to use on my XBMC, and fortunately I found now two interesting ones.


One is a script called Navi-X. I had that on my old version of XBMC, but now it is really complete. A lot of films ready for you to watch online without having to download it first (but you have the option to do it. I don't because my connection just got upgraded to a 100Mbps FD, and it don lag anymore). I got on the scripts directory of the following plug-in:


This plug-in enables you to "automagically" install a lot of nice things. Being my recommendation, the National Geographic and Navi-X

After that I tried to find ITV catch up, since I like to watch some of its content, but I often forget to record on my PVR. Here is what I found:

XBMC - BBC iPlayer on your big telly

Well, yesterday, after a long log time without update, I decided to update my XBMC. XBMC is a media centre software that I run on my old XBOX, and that support all media types I need, plus some extras, like you tube, national geographic, and since yesterday BBC iPlayer (it is really great to get it on a 32 inches monitor) fifth.


One of the best features it has is the ability to connect to a SMB share available on the network, and since last November I have a 1TB hard drive attached to my main router, making this space available to my Xbox. So from it I have access to all my libraries, including films, music and photos.

It is amazing how the software evolved in the last two years. From a Mplayer skin that ran on the Xbox, to a fully functional media centre software. I'm running right now a Beta version distributed from the SVN, but with all the brand-new functionalities.

Included in those functionalities the brand-new plug-in system, which now enables developers to write new media support to XBMC, like the BBC iPlayer. So, if you are interested in this, here is the URL:


If you want to know more about it, I recommend this article on how to convert your Xbox, and to understand how you can build an amazing media Center with less than £30.

If you are outside the UK, the restrictions on BBC content still apply, but there are other different plug-ins to other different services.

Back to Track!

After some time without posting I intend now to resume my activities within the Blog. I will try to post again at least once a week.


Probably very soon it will move to a different URL (personalised), so keep looking here for news.

So sit tight and enjoy!!!

Saturday, 2 August 2008

Stopping painfully slow backup on itunes/MAc and firmware 2.0

Well, I have been suffering for a long time from this issue. Every time I want to syn my iTouch wiht my mac, it takes ages. After googling a bit for a solution, it is straightforward:


1. - Quit iTunes.
2. - Open Terminal.app
3. - Copy and paste this in, then hit return:

defaults write com.apple.iTunes AutomaticDeviceBackupsDisabled -bool true

4. - Copy and paste this in, then hit return:

defaults write com.apple.iTunes DeviceBackupsDisabled -bool false

5. - Open iTunes
6. - Plug in your iPhone (2.0 or 3G) and sync.

Monday, 14 July 2008

Latex goodie - How to watermark things in Latex/PDFLatex

I have been having problems since ever when trying to distribute some content to people and keeping track of the NDAs I make them sign. A sound solution (good but not really impossible to break) is to watermark the documents before sending. Then if you detect it in the wrong hands, you can ate least trace who did it.

I had for a long time a code to do this, but the real problem was that this code was actually in TeX, meaning that to make it appear in a PDF I have to convert from dvi to ps and then to pdf. I real pain, plus you finish loosing all the goodies from pdflatex, in term of hyperref.

I found a site[1], and with his instructions I managed to produce my own code to put the copyright watermark in my pdflatex documents, here it is:

\usepackage{graphicx,type1cm,eso-pic,color}

\makeatletter
\AddToShipoutPicture{%
\setlength{\@tempdimb}{.5\paperwidth}%
\setlength{\@tempdimc}{.5\paperheight}%
\setlength{\unitlength}{1pt}%
\put(\strip@pt\@tempdimb,\strip@pt\@tempdimc){%
\makebox(0,0){\rotatebox{45}{\textcolor[gray]{0.95}%
{\fontsize{3cm}{3cm}\selectfont{Final Version}}}}%
\makebox(-100,-300){\rotatebox{45}{\textcolor[gray]{0.95}%
{\fontsize{2cm}{2cm}\selectfont{Internal Use}}}}
\makebox(-500,-0){\rotatebox{90}{\textcolor[gray]{0.95}%
{\fontsize{0.7cm}{0.7cm}\selectfont{\textcopyright Copyright 2008 - Jean Martina}}}}
}%
}
\makeatother


You should put this code in your preamble, and it will put a watermark in all your pages. You can change the texts and their positions quite easily, just try it.

[1]- http://filoxus.blogspot.com/2008/01/how-to-insert-watermark-in-latex.html

Latex Reference

Well today while surfing to find some things in Latex I discovered the following site:

http://en.wikibooks.org/wiki/LaTeX


This site brings a full reference for people using latex. The good thing is that they have a lot of examples that you can copy and paste and use in your documents.

Saturday, 12 July 2008

Ipod Touch V2.0

Well I took a decision today. Upgrade my jailbroken iTouch 1.1.4 to 2.0. The upgrade was smooth. You can do it via the new iTunes by paying $10. Safe and sound. Or you can got in the wild and do an upgrade by other means. If you choose the second options‚ remember:


  • Put the the iPod in recovery mode: Hold the home and power button until the iPod turns off. Then wait until you see your iPod turn on with the apple logo. Let go the power button‚ while still holding the home button. When you see the " Connect to iTunes" logo‚ you are in recovery mode.
  • Find the firmware somewhere
  • plug you iPod in the usb cable and go to iTune. 
  • cancel the automatic firmware install. click the restore button with shift key pressed (mac alt/option)
  • chose your firmware‚ and wait. It takes about 15 minutes to load
That′s it. But remember‚ if you love the Installer‚ there is no jailbreak software available yet‚ although the Dev Team‚ already claimed a jail break in it.

Monday, 7 July 2008

The Collection of Computer Science Bibliographies

I received from a friend other day the following link, and it is worth posting:

http://liinwww.ira.uka.de/bibliography/index.html

If you are a CompSci (Computer Scientist), you probably know the pain to arrange bibtex bibliography. This search engine gave me the right bibtex entry every single time I tried.

How to test Qmail+vpopmail for SMTP AUTH

Well, every time I need to check whether an installation of an email server is completely working I need to search google for this bit of information. Sometime is hard to fin exactly what you want. Suprisingly some of the examples don work with qmail.

To generate the AUTH string you need to issue the following command:

perl -MMIME::Base64 -e 'print encode_base64("\000user\@domain.net\000my.password")'

If you are using qmailrocks instalation, perl should have everything to handle this. If should generate an string like this:

AHVzZXJAZG9tYWluLm5ldABteS5wYXNzd29yZA==

To test you qmail instalation do the following:

> telnet newserver.net 587
Trying 123.123.123.1...
Connected to newserver.net.
Escape character is '^]'.
220 smtp.newserver.net ESMTP
ehlo my.machine.net
250-smtp.newserver.net
250-PIPELINING
250-8BITMIME
250-SIZE 0
250 AUTH LOGIN PLAIN
AUTH PLAIN
AHVzZXJAZG9tYWluLm5ldABteS5wYXNzd29yZA==
235 ok, go ahead (#2.0.0)
mail from:
250 ok
rcpt to:
250 ok
data
354 go ahead
Subject: Test

Test
.
250 ok 1215413930 qp 87194
quit
221 smtp.newserver.net
Connection closed by foreign host.

This should deliver the message (if you chnage the fake emails and server name to your reality). If you get any other message, your smtp auth is not working with qmail.

Sunday, 6 July 2008

Migrating between two qmail + vpopmail (qmailrocks) servers

This was my problem for today, how to migrate sound and safely from on old system running around 100 domains to a brand new configured qmail system. Both are running with the configuration suggested by www.qmailrocks.org and on a FreeBSD machine. So lets go:

  • First things stop the old qmail server to avoid loosing messages. Remember that you need to stop qmail from receiving any messages, and also stopping users from retrieving their email with pop3 or imap. The following commands would do it for you:
qmailctl stop
/usr/local/etc/rc.d/imap.sh stop
/usr/local/etc/rc.d/imaps.sh stop


  • After yo stopped qmail and the pop/imap daemons, you are able to start to transfer the vpopmail contents. Using rsync is a good idea, since that with it you can minimise the downtime, since you can run it in the hot system , before starting. This run is just to sync from the last call to the time you stopped qmail with the commands above. You are running this in your new server and server.xxx.com is you old server.
/usr/local/bin/rsync -avz --delete -e ssh root@server.xxx.com:/home/vpopmail/domains/* /home/vpopmail/domains

  • Luckily after some time rsync will finish running. If not, leave it working while go to change the other bits. In order to make the new machine recognise all the users and domains from the old server, you need to do the following:
import(merge) from the old server /var/qmail/assign
import(merge) from the old server /var/qmail/recipients
import(merge) from the old server /var/qmail/control/rcpthosts
import(merge) from the old server /var/qmail/control/virtualdomains


  • To finish add and delete a fake domain using vpopmail. This will make vpopmail read all the files you merged and reorganise them.
From now on, you just need to test the system to assure you got everythings working. A good idea before changing the DNS system is to configure an email client with the ip address of the new server an try to send and recieve some emails using all possible combinations.

Finally, keep checking the email server for a day. It is almost impossible to make everything work without mistakes.

Thursday, 3 July 2008

Creating Multiple Volume .tar.gz files

Well, today I came a cross a problem: I have to backup a 29GB file system to recreate it under the new rules here (I have ReiserFS, and as the guy is jailed for killing his wife, the policy is to convert everything to ext3, since it tends to be unmaintained). My external HDD is formatted in FAT32, for compatibility issues (Use in Mac , Linux and windows machines).

I did some research, and to create multiple tar.gz files, you need to use a combination of FIFO, split and tar. First you need to create a FIFO file (which can be reused in later uses):

mkfifo /tmp/test.fifo

After you can issue the following command line to generate the files:

split -b 200m /tmp/test.fifo /media/UNTITLED/filename.tgz- | tar -czvf /tmp/teste.fifo .

Basically what I am doing is sending the tar output to the FIFO (First In First Out), and then splitting the FIFO in 200MB files.

To recover things from the tar.gz file you just need the following:

cat /media/UNTITLED/filename.tgz-* | tar zxvf -

This should put all the bits back together.

Thursday, 29 May 2008

Digging the past of the Internet

This week I came across one very interesting web site. I was listening the TWIT (This week in tech‚ with Leo Laporte and John C Dvorak) and one guy that was invited to the show was the founder of this site. When he told the features‚ I said: " no way‚ some one can index the Internet historically"‚ but yes‚ he did

The site is www.archive.org. It contains a bunch of interesting web site‚ dating from 1996 up today. If you want‚ you can give a try in some of them. I suggest google‚ and microsoft‚ but be afraid to test other things. Even my very old page in geocites is available there.

Wednesday, 21 May 2008

Very interesting Security device

Today while listening to "Security Now" podcast, the guys mentioned about Yubikey, and I went out on some google search about it. Look very interesting and promising. The designs they developed is really nice indeed.

From the developers:

"The Yubikey is a new authentication solution, designed for the mass market of web 2.0 applications. The user inserts the YubiKey in any computer with a USB port on any platform or browser – no client software install needed – then press the YubiKey button to generate a one time passcode.

The secret behind the YubiKey is the fact that the little device is actually a USB keyboard. But with only one button and designed to do two things: To generate the user’s unique identity and a one time pass code that only works the very second it’s used. Every time the user presses the button it generates a new pass code."

More information can be found at:

http://www.yubico.com/products/yubikey/

Tuesday, 20 May 2008

Costumers tracking

Well after reading the latest news from the times:

http://technology.timesonline.co.uk/tol/news/tech_and_web/article3945496.ece

It raised some concerns to me:

- If they detect were you are, they can correlate this data with the CCTV system, and also the shops can correlate your IMEI with you credit card, and so on. Data minig is really powerfull in this cases.
- If this technology is really deployable, don't hey have to at least inform users? So you can turn off your mobile to avoid being tracked.
- If this technology goes to the wrong hands, what would impede people of selective killing others? Something like Bruce Scnheier's idea on road side bombing triggered with RFID passports.

The thing is that, here in the UK people don't often carry their (RFID) passport arround, but for sure, everybody carry at least one mobile.

Really scaring.