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The Cloud and our stuff

Everyone who works, studies or likes Computer Science and overall Technology, knows that for sometime now the buzzword on the internet is the “Cloud” and the vision that everything we have in our hard drives will be taken to these big company servers, and we will reach that data through our regular notebook, tablet or smart-phone (example). Our machine won’t need many storage neither processing capabilities because most of the work’s done on the server-side.

Well, the way this system works sounds great but (there’s always a but), in recent months we have been witnessing some of the downsides of this approach, like the personal information of million of users stolen from the “Playstation Network” or Dropbox security bug caused by an update (19/06/11), which allowed all user accounts containing private data to be accessible to anyone without password.  As a Dropbox user, this last one affected me but fortunately I’m not a big fan of storing my stuff in the Cloud(I only have some shared folders at the service), yet this makes me wonder if I can trust my stuff to someone else and how can I guarantee that my data remains private?

I’m not against the idea of the “Cloud”, it has many advantages and certainly those guys handling private data of thousands of people know about security than I do, but these recent failures and the possibility that this services could be attacked makes me want to do something to reinforce my stuff’s protection.

So what can we do?
I think to solution to this problem is to add client-side encryption to all the data we store online. This way I can guarantee that I’m the only one who has the password/key to get access to my stuff. So for those who already are Dropbox’s users the online blog LifeHacker proposed using TrueCrypt to accomplish this. You can also try Secretsync which is still in beta but it is a nice idea.
For those who lost all their confidence in these kind of services but still want their data synchronized through all computers (office, home, …) there are open source solutions that require a little more computer skills and/or a server, such as OwnCloud and Syncany.

Summing up, you have to be careful with the way you put your data in the cloud, to stay secure encrypt your files before the upload. This security bugs are bad for the user but they are even worst for companies because their reputation never will be the same, especially if they don’t warn the users.

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Simple Ceaser-Cypher

Some weeks ago i found this website called “Programming Praxis“, where you can find exercices to practice your programming skills. So every week they post a new problem and a possible resolution (it’s better if you only see it after you’ve done yours), and people try to solve and add a comment with their solution which is fun because you can see diferent ways of thinking in diferent languages.

So i will try once in a while (when time isn’t short) to solve some problems and post here my solutions (generally in python, but i will try other languages too). For this first time i have picked an old and simple problem posted in 2009 (here) about the Ceaser-Cypher which is basically an ancient, simple an totally insecure encryption method, where you add 13 to every letter in the sentense (example: “a” + 13  =  “n”) and when it reaches “z” you return to “a” (example: “t” + 13 = “h”).

So here is the function and the answer to their question:

def ROT13(string):
	new_string=""
	for i in string:
		letter=ord(i)
		if (letter>=65 and letter<=90) or (letter>=97 and letter<=122):
			if letter<=90 and letter+13>90:
				new_string += chr(64+(letter+13-90))
			elif letter<=122 and  letter+13>122:
				new_string+=chr(96+(letter+13-122))
			else:
				new_string+=chr(letter+13)
		else:
			new_string+=i
	return new_string 

Question: What is the meaning of “Cebtenzzvat Cenkvf vf sha!”?
Answer: Programming Praxis is fun!

P.S: I know that the solution could be more elegant but for now this one does the job

So i will try once in a while (when time isn

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Game Graphics: the road done so far

Today i was amazed when i found a trailer of the upcoming “Tomb Raider” video game. It got me thinking about how awesome computer’s 3D graphics are today and how they were when i got my first console. Nowadays i don’t have the time (neither the computer) to play any game but from time to time i watch some videos and look at some screenshots of actual games and they look pretty realistic (here is an example).

So, for those who doesn’t follow the game industry nowadays, i will show one video from the first “Tomb Raider” game (looked amazing back then) and the one that i saw today (you will notice the diference for sure).

Now:

Back then:

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A message to my Portuguese fellows

I know that we are in a deep hole and will be very dificult to get out of it, but we will have to do it. So here is a little message to give you some hope:

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Dark Matters, …

… is the name of the animation that i found in aindaapensar.blogspot.com while reading today’s posts at Planet Geek. It’s very educational and the creators made a very nice job turning those contents into something understandable for us, common mortals. So for those who think that everything already have been discovered, here it is:

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Gulf of Mexico oil spill

While i was surfing on the web i found a video, in a blog post, which was published 3 days ago to remember the environmental disaster that was the last year’s oil spill. It’s a short animation that gathered the estimated amount of oil that went to the sea and tries to split it in his uses, to give us the notion of the real size of the damage.

Take a look on one reason why it’s urgent to reduce our oil dependency.

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E-mails: hours to seconds

I remember those old times when i didn’t know nothing about computer programming and i was a member of the organization of the National Meeting of students of physiotherapy and after a conference about physiotherapy and spine related problems. At that time when we had to send some hundreds or even thousands of emails for other students and professional on that field, we spent hours or even days.

One of the problems was that our email provider (Gmail) didn’t allow to send a single email for more than ‘x’ people or send more than ‘y’ emails a day,if you had exceeded the limit they would block your account for the next 24 hours. For that problem the solution is don’t use Gmail for what it isn’t intended for. There are plenty other services to do that.

The other problem was the use of large files, full of emails adresses that we had to split through many emails. For this one, here is a possible solution, a script that connects to a SMTP server and sends the message to every contact in the “.txt” file.

import smtplib
from email.MIMEText import MIMEText

def send_to_all(server,login,passwd,subject,msg, cfile):
	contacts=open(cfile, 'r')
	email=MIMEText(msg)
	email['Subject']=subject
	email['From']=login
	
	smtp=smtplib.SMTP(server, 465) #change for 587 if doesnt work
	smtp.ehlo()
	smtp.starttls() #comment this line if the server doesnt support TLS
	smtp.login(login,passwd)
	
	for item in contacts:
		smtp.sendmail(login,item,email.as_string())
		
	smtp.close()

def main():
	#Asks the info to the user
	print "Server: "
	server=raw_input()
	print "Login: "
	login=raw_input()
	print "Password: "
	passwd=raw_input()
	print "Subject: "
	subject=raw_input()
	print "Message: "
	msg=raw_input()
	print "Contacts file: "
	cfile=raw_input()
	#sends the message to all contacts in the file
	send_to_all(server, login, passwd, subject, msg, cfile)
	return 0

if __name__ == '__main__':
	main()

With this script you can only send simple text messages, but it might be usefull for someone anyway.

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When UC website gets confused

Bug or not, this is what happens when i try to access my university’s new website with two common browsers:

UCbroswerfail2 UCbroswerfail

Both browsers, at the time of the screenshots, were with their latest version and the message doesn’t always appear, that’s why i called it “confusion”. But the fun part is:

UCbroswerfail3

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Coimbra Startup Weekend: to go or not to go?

coimstartweekend

It seems to be a nice event and a well spent weekend with lots of things to be learned.

I don’t know if i’m the kind of participant they are hoping for or even if i’m ready, but nevertheless i’ll stay tunned for more information.

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Old Posts

Teleconferencing: The Kinect Way

Well, i was reading some of my usual blogs and news websites, when i found an article about this new MIT Media Lab project, the same “guys” that brought to us the Sixth Sense idea (this one I posted in my old blog).

I first saw the video in this engadged article and it looks awesome, please take a look at it:

It looks great! right?
I’ve done some research about this lab and it seems that they have lots of amazing ideas, i’ll try to follow and maybe write here a little bit more about some of their stuff that i find interesting.