technology blog

Friday, 15 July 2011

Want to rent a movie tonight? Can you calculate how much it'll cost you?

Or how many movies can you rent on iTunes in a month?

For demonstration purpose, let's say you love "Funkytown", you are silly and you want to rent it multiple times within a month. Its HD version is 4.6gb at a price of 6.99$ on the iPad. For consistency, I'm taking ISP's cheapest package above 5mbps and assuming you have another service with the ISP to have reduced cost.

ISP Province Monthly price BandwidthAllowanceExtra
Vidéotron Québec 43,95$8mbps50gb4.50$/gb max 50$
RogersOntario46,99$10mbps60gb2.00$/gb max 50$
Bell Québec 42,95$7mbps60gb2.50$/gb unlimited cost?
Bell Ontario 43,90$6mbps25gb2.50$/gb unlimited cost?

With most ISP, you would be able to rent up to 13 movies in a month, if you are not ever watching Youtube videos at 135mb/hour, going to tou.tv, doing Skype or Hangout on Google+ at 720mb/hour. And don't ever think about installing your latest operating system service pack, for each of your computers and laptops, which sometime weights near a gigabyte.

If you have a family, think teenagers watching Bieber in a loop and blow up the monthly cap, you'll end up renting the 11th movie on Vidéotron at an effective cost of 6.99$+4.6gb*4.50$/gb = 27.69$. Yes, it's ridiculous.

I do welcome the extra bandwidth cost bounding. I think it puts a fair balance between limiting heavy usage and extortion. But the extra bandwidth cost is usually unbounded for business accounts, like mine. This puts small businesses in an even weaker position, as they can't afford to not have internet access and usually have multiple concurrent users on a single connection. In fact, small businesses are the ones that are losing the most of this situation.

Now think about it, most independent ISP have caps around 200gb, which would permit you to rent 43 movies in a month, which makes more sense as an upper limit.

Network bandwidth is not like water or electricity; an idle router and a congested router have both the exact same cost. As a counter point, a congested router will have lower throughput than a non-congested one so there is need to balance usage. It's fair, we don't want to have too many congested routers, causing slow connections. My point is that having unbounded extra cost, especially above 1.00$/gb, is nearing extortion and in particular for small businesses.


(note how the details are hidden in a faq on a almost unbranded site)


I work for Google but I did this research on my own time. It doesn't represent the opinion on my employer. I pay for my extra bandwidth.

Thursday, 14 April 2011

Putty configuration

Saving my preference here since I always forget:

  • Session
    • Close window on exit: Always
  • Terminal
    • Bell
      • Taskbar/caption indication on bell: Steady
    • Features
      • Disable remote-controlled window title changing: True
  • Window
    • Lines of scollback: 2000
    • Behaviour
      • Window title: <session name>
      • Separate window and icon titles: True
      • Warn before closing window: False
    • Translation
      • UTF-8
    • Colours
      • ANSI Blue: 0, 0, 242
      • ANSI Blue Bold: 132, 132, 255
  • Connection
    • SSH
      • Remote commands: "screen -x"
      • Preferred SSH protocol version: 2 only
      • Encryption cipher selection policy: Move up "--warn below here --" to only leave "AES (SSH-2 only) enabled.
      • Tunnels
        • <Set relevant tunnels>
Set as startup program: "...\pageant.exe ...\<private key>.ppk"

Friday, 11 March 2011

Generating passwords

Note to myself as I always forget. How to generate a (mostly) uncrackable password:
sudo apt-get install apg
apg -m 9 -MLNS -a0 -t
This request: min 9 chars, must contain lowercase,  numeral, and symbol, be pronounceable, and print the pronunciation.


  • Prepend /! for irc&bash safety.
  • Append any accented letter in (non-exclusive) çÇ àÀ­áÁäÄâ éÉèÈëËêÊ íÍìÌïÏîÎ óÓòÒöÖôÔ úÚùÙüÜûÛ ýÝÿ ±£¢¤¬¦²³¼½¾¶§µ¯­­­. All these letters can be seamlessly typed from a FR-CA keyboard with AltGr or two keys combination.
    • You can simplify the apg complexity because of this one since it's adding many letters of entropy and each of these letters is ~3 bytes of utf-8, dramatically increasing the effective password length.
    • If you are selecting your password on linux, don't forget that Windows won't accept certain combinations like ȩȨ ÝŸŷŶ. You may want to not use them if you ever plan to login from a windows workstation.
    • «»° aren't accessible on all FR-CA keyboard so you need to memorize the Alt-Numlock combination.
    • Similar alternatives for Spanish people: ¿¡
  • You now have a password that:
    • is mostly copy-paste safe
    • is uncrackable by most rainbow tables. Who generates a utf8 rainbow table with ½ or µ with length of 12 characters?
    • will probably not be accepted by most web sites since it's too secure. :(

Wednesday, 19 January 2011

1 kibioctet = 1023,937522 octets

Vous cherchez à propos de l'affiche installé dans votre université? Je fais une présentation à propos de la corruption silencieuse de données le 27 janvier à l'École Polytechnique de Montréal et le 28 janvier à l'Université Laval à Québec.

Mais en premier, trouvez la réponse à l'énigme.

Bonne Chance!

Note: certains chercherons peut-être 1 kibioctet = 1023.937522 octets même si l'affiche utilise une virgule.

Mise à jour #1

Si vous avez de la difficulté à trouver la réponse, je vous conseille d'appliquer:

Mise à jour #2

L'énigme n'a rien à voir avec 1024 en particulier.

Mise à jour #3

Monsieur Munroe a fait une coquille en écrivant ce nombre.

Mise à jour #4

En rapport avec l'indice précédent, si vous donnez un url comme réponse, "/394" en fera partie.

Mise à jour #5

Le tout a été causé par un manufacturier.

Mise à jour #6
(Mis à jour 2011-03-29)

Visitez maruel.github.com pour voir la présentation.