Desgrange.net

Email protocols history

A long time ago there was several protocols to send a message from a computer to an other one. There was a protocol per network (the internet was not really born at that time). Those protocols were not compatible between each others. So for instance, if you were using FidoNet, you were not able to send emails to people using BITNET. Hopefully some people created some gateways to transfer emails from a network to an other one (but it looks like it was quite a nightmare). At some point in time, ARPANET and its email protocol became the standard and other protocols started vanishing. People were now able to communicate with each other easily.

Instant messaging

Instant messaging (IM) appeared much more recently (email started in the late 60s, late 80s for IM). Personal IM became very well known in 1996 with ICQ (I still have my ICQ account! (but nobody to talk to on it anymore)). Then several other protocols appeared:

• Jabber (1998, free and open protocol)
• QQ (1998, closed and proprietary)
• Yahoo! Messenger (1998, closed and proprietary)
• MSN Messenger (1999, closed and proprietary)
• …

Of course you can't chat with somebody using MSN Messenger if you use Yahoo! Messenger. ICQ was bought by AOL, AOL created AIM (AOL Instant Messenger) based on ICQ protocol. At some point people using ICQ were able to speak with people using AIM.

In 2004, XMPP, the protocol used by Jabber, became the official IETF instant messaging standard (IETF is the group defining the internet standards (like HTTP for the web, SMTP for emails, FTP for file transfer…)).

Jabber/XMPP

XMPP as been the standard for 5 years now, but still, most of my contacts are using MSN Messenger. Why? Because they also use a Microsoft Windows based computer and Microsoft MSN Messenger is the default instant messaging software installed on those computers.

XMPP allows creating gateways to other protocols (like MSN, Yahoo!, ICQ…). The situation looks a bit like the email status in the old days. But the email standard imposed itself as the killer application of ARPANET. So, what will be the thing that will wipe out all proprietary protocols and impose the XMPP open standard?

The problem with standards is that it take time to be developed. History as shown that new versions of a standard are not implemented by all software vendors quickly, nor they are deployed as fast as possible. So changes to the standard must not happen everyday and having it quite right at version 1.0 take time.

In the meantime, other protocols evolve faster because vendors have a captive market and a better control on how the software is distributed/used (and they don't have to wait for others to implement changes).

While XMPP was on the way to be standardized, other protocols got voice then video functionalities. I had a lot of hope in 1995 when Google released it's own IM software Google Talk. GTalk is based on XMPP and add some voice extension and video extension later.

Then AOL started an experiment to allow XMPP connections to its network, Yahoo announced that they were interested by XMPP too. The chat in Facebook uses XMPP (but the network is closed, you can only talk to Facebook users), several other community websites do the same.

Nowadays

Last week, the specifications for voice/video in XMPP were released. The biggest missing features making people stay with their proprietary IM is going to be old story soon. But I'm not sure it will be enough to see a big migration to XMPP.

Those last few years, XMPP interest increased a lot and nearly all IM vendors are now looking at XMPP… except Microsoft. It looks like you will soon have the choice between speaking to nearly everybody except MSN Messenger users or speaking only to MSN Messenger users.

Of course there are lots of softwares allowing you to use several accounts at the same time (so being connected to MSN, Yahoo! and Jabber at the same time). I also have several emails account. The difference is that from my professional email account I can send emails to everybody, same for my personal email. I'm choosing the email account I'm using depending on what my "role" is. If I want to send a message to a colleague, I will use my professional email address.

In IM, you can't do that, except if you open several accounts on each protocol you use. Having a professional and a personal account on MSN, on Yahoo!, on AIM, on Jabber… With all those protocols I currently have 9 accounts. And you know what? I like keeping things simple. For my email addresses I have started closing several accounts, keeping only the mandatory ones (my personal email address and the ones I have to use for my job). And I would really like doing the same for IM but you know what? Here I can't do what I want. Why? Because if I close my MSN account, I will lose contact with a lot of people.

I feel a bit like in jail. Worse, I feel like my friends are in jail too but they are saying "Where do you see a jail? There's only walls and fences".

Anyway, lots of people are using GMail now, and there is a chat embedded in GMail. Of course this chat uses Google Talk so it uses XMPP. Even if I don't really like GMail, I prefer having my friends using GMail/Google Talk than Hotmail/MSN Messenger (or whatever the name of those services are this week).

ejabberd

Since XMPP is an open protocol, anybody can implement it. There are several XMPP clients (Pidgin, Adium, Kopete, Trillian, iChat…) and there are also several servers.

In XMPP servers there is well-known one: ejabberd. This server is open source and written in Erlang. Ejabberd use the power of Erlang to be fault-tolerant, redundant, scalable, <add here any cool property a server should have>.

And since XMPP is a decentralized system, I can install my own server (as I did for my email server for instance).

Installing ejabberd on debian is as easy as usual:

$ sudo apt-get install ejabberd

To configure it, you just need to change the domain name to serve in /etc/ejabberd/ejabberd.cfg. If your domain name is example.org change the following:

%% Hostname
{hosts, ["example.org"]}.

And set the admin user:

%% Admin user
{acl, admin, {user, "admin_user_name", "example.org"}}.

Add a user with the following command:

$ sudo ejabberdctl register user_name example.org password

Restart the server. Done.

Of course there are a lot more parameters to change if you want to fine tune it. You may also need to create a SRV entry in your DNS if your server is not the one serving "example.org" (but "im.example.org" for example).

As you know, the web is based on standards, those standards give us the ability to access all the data on the web whatever our browser and/or operating system are.

But Microsoft didn't care much about web standards when they were building their own web browser: internet explorer. IE had more than 90 % market shares for a long time but nowadays it's less than 70 %, because of new browsers (more secure, faster, more standard compliant, etc.).

So Microsoft updated it's web browser with IE 7, which is a bit more standard compliant but far away compared to other browsers like Chrome, Konqueror, Firefox, Opera or Safari.

Unfortunately, lots of web sites were developed to be usable with IE 6 (which still have nearly 18 % market share), and IE 6 is so buggy that's a real pain to have a good website being usable with IE 6.

Web standards give us the power to create wonderful websites, web applications, but we usually can't because we have to take IE 6 users in account.

The content of my blog should not attract IE users but here are the usage:

• Firefox: 52 %
• IE: 21 % (IE 6: 45 %, IE 7: 50 %)
• Safari: 10%

Somebody had the great idea to start a campaign against IE 6 (I hope, if the goal is met, he is going to create a new campaign for IE 7 which is not a lot better):

The goal is obviously to wipe out IE 6 by telling people still using IE 6 (or older!) to switch to a newer browser (you can add a little script on your website warning IE 6 users that they should update their browser).

Petit récapitulatif de l’utilisation des préfixes en informatique.

Il y a une confusion assez généralisée sur l’utilisation des préfixes en informatique et je pense qu’il est bon de rappeler une fois de plus ce que disent les standards.

Le Système International défini les unités des grandeurs physiques (comme le mètre ou la seconde) mais aussi les préfixes que l’on peut y appliquer.

Les préfixes sont par exemple le “kilo” qui est un multiplicateur de valeur mille. Le but des préfixes est de simplifier l’utilisation des unités, par exemple :

• “la lune a une masse de 73 zetta grammes” au lieu de :
• “la lune est super lourde a une masse de 73 000 000 000 000 000 000 000 grammes” ou encore :
• “la lune a une masse de 73 sextillions/trilliards de grammes (suivant l’échelle utilisée)”.

Ces préfixes sont des multiplicateurs ou des diviseurs à base de puissances de 10, quelques exemples :

• 10³ = 1 000 = mille = kilo (k)
• 10⁶ = 1 000 000 = 1 million = méga (M)
• 10⁹ = 1 000 000 000 = 1 milliard = giga (G)
• 10^-3 = 0,001 = 1 millième = milli (m)
• 10^-6 = 0,000 001 = 1 millionième = micro (μ)
• 10^-9 = 0,000 000 001 = 1 milliardième = nano (n)

Voilà pour les préfixes de la vie de tous les jours, où l’homme compte en base 10 (système décimal). Mais voilà, l’informaticien travail sur des machines binaires qui comptent en base 2 (système binaire)

L’informaticien aussi veut pouvoir se simplifier la vie avec des préfixes, mais ses préfixes sont en puissances de 2 au lieu de puissances de 10. Voici quelques exemples de préfixes binaires :

• 2¹⁰ = 1 024 = kibi (Ki)
• 2²⁰ = 1 048 576 = mébi (Mi)
• 2³⁰ = 1 073 741 824 = gibi (Gi)

Exemple d’utilisation : 12 Mio = 12 mébi octets = 12 * 1024 kibi octets = 12 * 1 048 576 octets

Ces préfixes binaires ne font pas encore parti du Système International mais ont déjà été normalisés : CEI 60027-2, IEEE 1541, EN 60027-2:2007

J’espère qu’un jour les systèmes d’exploitation afficheront les tailles de mémoires dans les bonnes unités et que les procès contres les sociétés affichant les caractéristiques de leurs disques dur correctement arrêtent (ces procès ont lieu aux états-unis, un des rares pays n’utilisant toujours pas le Système International)