June 2012

Brain dump and Technology and The media26 Jun 2012 at 13:42 by Jean-Marc Liotier

/set rant_mode on

A digit is a numeral from 0 to 9 – so the French translation is “un chiffre”. Surprisingly, I find myself having to add that the French translation of “a digit” is not “un doigt” – you may use your fingers for counting, but in the end it is all about numbers not body parts.

Therefore the proper translation of “digital” in French is “numérique” – the French word “digital” describes something related to fingers. A digital device may be finger operated, but its digital nature is related to binary processing… The presence of a keyboard is accessory.

Increasingly, I find my compatriots using “digital” to qualify anything run by computing devices without having to mention them by name – because computers, data processing, electronics and such drab technicalities are uncool compared to the glittering glitz of mass-marketable trinkets. I resent this lamentable technophobic trend but, if you want to indulge in such decadence, please at least use the proper French word.

From now on you’ll know that any French person caught saying “digital” instead of “numérique” spectacularly exposes his ignorance – you know who they are and you are welcome to anonymously report them in this article’s comments (with links to incriminating tweets for bonus ignominy).

I obviously don’t mind people using English. I don’t even mind loan words – they are part of how a language evolves. But I do object to mindless namespace pollution: using loan words does not exempt from semantic coherence.

Call me pedant if you want, but if you attempt to degrade our essential communication tools you’ll find me on your path and I’ll be angry !

Networking & telecommunications and Systems administration and Unix06 Jun 2012 at 11:48 by Jean-Marc Liotier

Today is IPv6 party time so let’s celebrate with a blog post !

Reliable IPV6 connectivity is no longer just nice to have – it is a necessity. If your Internet access provider still does not offer proper native IPv6 connectivity, your next best choice is to use an IPv4 tunnel to an IPv6 point of presence. It works and on the client side it only requires this sort of declaration in /etc/network/interfaces :

auto ipv6-tunnel-he
  iface ipv6-tunnel-he inet6 v4tunnel
  address 2001:170:1f12:425::2
  netmask 64
  gateway 2001:170:1f12:425::1

Of course, the same sort of configuration is required at the other endpoint – which means that, among other parameters, you must inform the IPv6 tunnel server of the IPv4 address of the client endpoint. Hurricane Electric, my tunnel broker lets me do that manually through its web interface – which is fine for a static configuration done once, but inadequate if your Internet access provider won’t supply you with a static IPv4 address. By the way, even if, after a few weeks of use, you believe you have a static address, you might just have a dynamic address with a rather long DHCP lease…

But Hurricane Electric also provides a primitive HTTP API that lets you inform the tunnel broker of IPv4 address changes – that is all we need to do it automatically every time our Internet access goes up. Adding this wget command to the uplink configuration stanza in /etc/network/interfaces does the trick :

auto eth3
iface eth3 inet dhcp
  up wget -O /dev/null https://USERNAME:PASSWORD@ipv4.tunnelbroker.net/ipv4_end.php?tid=34764

That’s it – you now can count on IPv6 connectivity, even after a dynamic IPv4 address change.

And after you are done, go test your IPv6 configuration and your IPv6 throughput !