email addresses are half case sensitive

The left hand part of an email address, the bit before the @ is case sensitive, in email in general. I've known that for a while - it seems to be an obscure-ish part of SMTP folklore.

Individual mail domains are perfectly at liberty to fold multiple distinct addresses into one, in their own domain, which is what most mail systems do: BENC and benc and bEnC all go to the same place @hawaga.org.uk. This leads many people to think that the left hand side is case insensitive.

This is just as they are at liberty to do that folding in other ways: for example, gmail ignores . in addresses, giving me b.clifford@gmail.com and bclifford@gmail.com. As well as b.c.l.i.ff.o.r.d@gmail.com

This came up on a mailing list (for browserid) that I watch, and I ended up being challenged in private email to cite a source. Luckily there's plenty of stuff around. RFC2821 section 2.4 seems to be the authority: The local-part of a mailbox MUST BE treated as case sensitive.

In the preparation of this blog post, I discovered something I didn't know before. It seems you cannot have multiple dots in a row in a plain email address. The RFC2821 production rules are:

      Local-part = Dot-string / Quoted-string
            ; MAY be case-sensitive

      Dot-string = Atom *("." Atom)

      Atom = 1*atext

where atext seems to come from the companion RFC2822 section 3.2.4. So b...clifford@gmail.com is not a valid address. Shame.

city of a thousand broken access points

Auckland seems to have wifi access points all over the central business district. But for the most part they don't seem to work. They seem either charge-based or needing-a-login-even-though-not-charging, and they all seem screwed up in that my equipment either can't associate to them, or when it does associate to them, it doesn't get an IP address via DHCP.

What kind of madness is this? that the equipment is deployed and then apparently neglected so much by all involved that it doesn't work enough to generate revenue...

yubikey input fail.

I've been using a yubikey to generate numeric OTP codes for logging into one of my servers when using friends PCs.

That's work well so far. But today I tried to use it on a french keyboard, where the "number" keys generate punctuation (the numbers are on the shifted version). Well, now, my yubikey then just enters a load of punctuation in place of the OTP code. Fail.

Automatic beep on arrival

I have an iPhone with no gsm connection, just wifi. It knows the password for a lot of places I hang out which has led to pretty much it always beeps when I'm standing in the doorway of where ever I was headed - just in case I hadn't noticed.