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Message de esperence posté le 2004-08-06 14:21:13 (S | E | F | I)
hello!!!
je cherche quelqu'un qui est fan d'informatique pour partager cette passion
thanks
esperence

Réponse: re:informatique de cloud, postée le 2004-08-06 14:30:33 (S | E)
MOI!!! ;)

Réponse: re:informatique de esperence, postée le 2004-08-08 15:40:03 (S | E)
c pas vrai!! toi mon unique amour

Réponse: re:informatique de jmdbxl, postée le 2004-08-16 18:42:59 (S | E)
moi

Réponse: re:informatique de yannloic, postée le 2004-08-17 09:35:40 (S | E)
I'm happy to see there are persons that likes computer here.

May be we can soon open a computer column here.

What are you interresing in ?

programming languages
systems administration
networks, protocols and gateway
servers and tools
systems deployement
free software movement and licensing works (GNU,GPL)
windows operating system
linux and Unix use
database applications
Web and ftp deploying
cryptography
distributed systems
algorithm

Choose one and I would try to talk you cleary and simply about.

Réponse: re:informatique de serena, postée le 2004-08-17 10:34:48 (S | E)
hello, yannloic

It's a very good idea.
what about cryptography?

Réponse: re:informatique de yannloic, postée le 2004-08-17 12:20:25 (S | E)
Cryptography, it's rather a hard subject to deal with. Though I'm a Unix system administrator, I must confess, I only understood not long ago.

I especially know GnuPg (GNU Privacy Guard) based on open PGP standard. It is a completly free public-key cryptography package.

First of all, you need to know what a key is.

Let's say you have a message. You know the game that consists to replace the letter by the next letter.

ex:

message becomes nfttbhf.

That is still not a key. A key could be the distance (the number of letter) you have to add to crypt (or scramble) the message.
A distance of 4 would mean thet the replacement for "a" is "e".

The scrambled message is then harder to decrypt than the one in the first example.

At the beginning the key was in the algoritms and you need the good software to crypt and decrypt message. It is useful to clarify the difference between the algoritm and the key.

An algoritm is a step-by-step recipe of logical order. A key is a value that we can use in place of a general term to implement the algorithm.

That way an algorithm of cryptography is general. A key makes it specific.

With this approach it isn't worth cracking the algorithm. Before if the algoritm was known, all crucial information were lost,a nd the algorithm couldn't never be used again. Now the key keeps the secret. The algorithms are general and known (DES algorithm for example), and if the key is found or revealed, yo just have to change it.

What I have just discribe is said to be a single-key encryption (for a sigle user). But when you have 2 users dialoging together, you have a problem; Do you see which problem ?

Réponse: re:informatique de maylynn, postée le 2004-08-17 13:34:23 (S | E)
ouaoou ! Yannloic avec toi je vais en apprendre des choses.
Mon domaine informatique est la création (amateur) de site web, pour le moment en HTML.
Et dès que j'en aurais la possibilité je m'attaquerai au PHP.
Excusez-moi de ne pas écrire encore en anglais, j'arrive à peu près à le lire, mais l'écrire...
Enfin disons, que pour l'instant vous me comprendrez beaucoup mieux en français !

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Edité par maylynn le 2004-08-17 13:41:30

Réponse: re:informatique de yannloic, postée le 2004-08-17 18:21:50 (S | E)
maylynn I'm not really a profesionnal of php, but I have already install some website. I can recommand you to get easyphp (association of mysql, php, php admin, and apache). With that package under Windows you have access to a local webserver, to try your web home, try php scripts, use a SQL database if you need. All is already is order to use. No problem.

From specifics tips (truc) please to contact our webmaster. He is shy, but he is a real ace of that programming thingamajig (bidule,-- I'm not sure it fits--).

Réponse: re:informatique de yannloic, postée le 2004-08-17 18:36:12 (S | E)
I see that noone follows. A real pity!

Well, well, well, the problem is that if the sender use a key, the reciever needs the same key. Of course they could meet each other in a pub. But it is not convinient. The sender could also send his key to the reciever. But then an eavesdropper can pick it up and decrypt the message.

You could reply me that the sender could send his key trough a trusted channel, but in that case you don't need to crypt your messages because the channel you use is trustfull.

The breakthrough in cryptography has come with dual-key encryption schemes. You need a key-pair one to crypt, one to decrypt, getting together, but that you can't derived one from the other (except this great inordinate computer efforts).

I need a rest for the following, to explain why the key generate for the reciever can be send in clear over the network, and why it is call a public key.

May be tomorrow, if someone is interested.

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Edité par mariet le 17-08-2004 19:05
Please, allow me :
if the sender use => if the sender useS
convinient => convenient
the reciever => the receiver
trustfull => trustfuL
you can't derived => you can't derivE (can + INFINITIVE)
the key generate for the reciever can be send in clear over the network, and why it is call a public key
=> the key generateD for the receiver can be senT in clear over the network, and why it is callED a public key
Comme dirait la pub : A quoi ça sert que le webmaster y se décarcasse à mettre des outils comme le vérificateur d'orthographe si personne ne s'en sert ? ;)

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Edité par mariet le 17-08-2004 19:17

Réponse: re:informatique de serena, postée le 2004-08-17 19:07:43 (S | E)
hello yannloic

thanks for your explanations. but it's so hard to do ! specially when I saw the magic message you wrote to alexpropov. waw !!
anyway, even if I can't promise I'll do, because for that we'll need 100 MP to write everyday ! ;) . and only for questions !
thank you once more.

Réponse: re:informatique de maylynn, postée le 2004-08-18 10:40:28 (S | E)
Thank you Yannloic for your informations of easyPhp.
Je l'ai déjà téléchargé, ce qui me manque pour le moment c'est malheureusement le temps !

Réponse: re:informatique de yannloic, postée le 2004-08-18 11:05:06 (S | E)
Thanks Mariet for the corrections, even if you are always a bit finicky.

Sorry I was in a hurry. To tell the truth, I use winword spell checker, because the site one doesn't correct grammatical faults. He doesn't correct inattention either.

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