Serviced espresso machine is serviced

All kinds of replacement parts for things have come in over the last few days, including new Tempest cells to rebuild the battery pack for my main UPS, and service parts for the Gaggia espresso machine.

The Gaggia had two problems.  First, it had begun leaking significantly between the filter holder and the brew head; and second, it had recently become very erratic about producing a consistent supply of steam for the milk steamer/frother.  Given that one of the neon indicator lamps in the main switch mostly stopped working (it would sometimes blink on for a moment) some years back, which I had always attributed to a loose connection¹, I'd assumed the most likely cause of the steam pressure problem was that eleven years of use had simply worn the contacts in the steam switch until it wasn't making good contact any more.  I've tried previously to servide the switch, but couldn't figure out a way to get the switch apart without breaking it.  So, given that we have a little extra cash on hand for once, I spent fifty dollars or so on a new main switch, a new filter holder gasket, and a blank 'filter' for back-flushing.

Swapping out the main switch was a trivial job, requiring only care in making sure all ten connectors went back onto the switch in the right places, a problem simply solved by moving connectors over from the old to the new switch one at a time (since the wiring harness is long enough to take the switch out without having to disconnect the harness first).  The gasket was a bit more of a problem, partly because it requires disassembling the brew head, partly because the old gasket had become so hard I couldn't get the point of a tool into it to pry it out.  I eventually resorted to driving two drywall screws into and through the gasket (which is a ring 58mm in diameter, 8mm wide by about 9mm thick) and using them to effectively push the old gasket out from the back.  This worked, even though the gasket had become so hard that it fractured at the screws instead of bending.

Of course, having the brew head completely stripped down again was a perfect opportunity to scrub it spotlessly clean with a fine stainless-steel-wire brush before reassembling it.  The new gasket slipped in with just finger pressure.  With a new filter gasket and new main switch, and a thorough cleaning, it was all ready to go again.

I will observe for the record (purely for academic interest, of course) that the first doppio cappuccino of freshly ground Kenya AA coffee out of a freshly cleaned and serviced Gaggia espresso machine is very, very good.

[1]  Since neon lamps contain nothing that can wear out, they have an effectively infinite service life short of either mechanical breakage of the bulb or a lead wire, the neon² diffusing out through the bulb, or the electrodes eroding away — either of which takes a long, long time³.

[2]  Technically, classic red neon lamps normally contain a Penning mixture of 99.5% neon and 0.5% argon.

[3]  Unless too much current is being driven through the lamp, in which case electrode sputtering can become a problem.

Crypto

Bruce Schneier is one of eight designers of Skein, an entrant for the NIST SHA-3 competition.  It's extremely robust, and has proven very difficult to attack.

Which is why a group of very clever cryptanalysts invented a completely new type of cryptanalytic attack to use against Threefish, the block cipher underlying Skein.  The crypto community is still trying to figure out how the new attack changes the crypto landscape.

Brilliant as it is, though, the new "known-key distinguisher attack" still didn't really work.  It was able to distinguish between a reduced-round — 57 of 72 rounds — Threefish ciphertext and a random permutation, but doesn't actually recover any key bits, requires that the attacker be able to manipulate both plaintexts and keys "in a structured way", and is only marginally faster than a brute-force attack.  Even then, it can only distinguish Threefish ciphertext, and doesn't actually affect Skein itself (yet).  Further, Schneier and the other Skein designers were able to identify a way to block the new attack by changing a single constant in Threefish's key schedule, which prevents the attack from being able to distinguish between Threefish ciphertext and random permutation beyond 33 of 72 Threefish rounds, and have made that change as a second-round tweak permitted by the NIST.

Still, it illustrates a point:  Both cryptography and cryptanalysis only get better over time.  When you run into a problem where none of the existing tools work, the truly clever cryptologist devises a new tool.

Content

LiveJournal has, as most of you already know, sprung another surprise on all of its users.  In brief, the feature is basically simple enough:  It allows LiveJournal users to automatically crosspost to Facebook or Twitter.

However, it is badly designed.  It has become apparent that it allows commenters responding to a locked post to crosspost their comments, possibly including quoted material from the locked post, to Twitter or Facebook — at which point it's essentially out there in front of the entire world.

This is obviously unacceptable.  LiveJournal really did not think this through at all, and the displeasure over it can be seen in the ongoing shitstorm in the comments on the news announcement (currently around five thousand comments).

Granted, I make most or all of my original posts on Dreamwidth these days, and thence crosspost them to LiveJournal — with the same privacy restrictions.  Suffice it to say that if I see fit to restrict a post for any reason, and I subsequently find that a commenter has exposed restricted content to the entire world, I will not be happy.

suzilem once posted the following disclaimer, which I enthusiastically adopted, in response to another site that had similar ramifications:

"I am not, nor will I ever be, a user of any service that defeats other journals' privacy filters."

It looks as though, unless they rethink and rework this "feature" in very short order, LiveJournal has become a service that DEFEATS ITS OWN privacy filters, in the pursuit of Facebook and Twitter eyeball share.  This is not a good path to go down, and I see a shark tank waiting at its end.