Christmas trivia... Last year we bought a new Christmas tree stand, the first one we've ever owned that actually did make it easy to set up our tree. Click on the image at right to take you to Amazon's page for it. We got our tree a couple days ago, and once again this year we had it up in just seconds, perfectly straight, with no rusty screws to tighten. These things are made in Germany, and the mechanical workings are quite clever. There's a water gauge, too – quite a handy thing, actually, because you no longer have to stick your finger in the water to see where the level is.
Something I saw last year at Home Depot, but stupidly did not buy, is a crazy-long funnel for filling the Christmas tree stand with water. I rectified that this year – I bought the one pictured at left. It's about 3 feet long, just the right length to let me stand alongside the tree while I fill the stand. I've filled it three times so far, and haven't spilled a drop of water yet. Genius!
And speaking of trees, here's a photo of our tree this year in the dark. It's a seven-footer, the perfect height for our living room. The lights on it are the same string of individually-blinking LEDs that we used last year – both of us love those things. They remind me of the “transformer lights” my dad bought for our tree when I was young. Those lights ran on 24VAC, and each bulb blinked individually. Those blinking incandescent bulbs used to be readily available, but not any more – I did find some a few years ago, but they were outrageously expensive and poorly made. Those bulbs worked mechanically, using a bi-metal strip that bent as it heated and cooled. The LED string we have uses electronics in each bulb; they should last basically forever.
Just as we did last year, we bought the tree from a family-owned Christmas tree farm from Kalispell, Montana. Their trees are beautiful specimens well cared for – not at all like the typical junky trees we see at the larger commercial outfits. One thing we particularly like about their trees is that they have a lot of natural variation. We like our tree a bit more sparsely branched than most people seem to like, as we want room for the lights and ornaments. The Robinson family sends a truck and a couple of employees all the way down here to Logan (about 500 miles) each year to sell their trees. When I looked them up on the Internet, I discovered they have a few other lots they sell from, all in northern Utah. It's an interesting story.
Those blinking bulbs were originally meant to simulate the really old-fashioned way to put lights on a Christmas tree: with candles. I remember one Christmas – just one – when I was dispatched to my grandparents house (on the same farm I grew up on) to help with their Christmas tree. This was while my great-grandmother was still alive and before my grandfather's terrible auto accident, so I'm guessing '58 or '59 – I'd have been 6 or 7 years old, and that feels about right. I remember clearly just two things about that experience. First was the tinsel. It was carefully packed in funny-smelling tissue paper, and had been used in many previous years. There wasn't a whole lot of it – maybe 50 strands – and my grandmother was very protective of it. The tinsel was made of very thin, very shiny metal – possibly actual silver (which is what tinsel was originally made of), stored in anti-oxidant tissue. My great-grandmother and my grandmother carefully placed each individual strand. I wasn't allow to touch it. :) The other thing I remember is the candles: dozens and dozens of tiny candles, slightly larger than what you'd see on a birthday cake. They were in small tin or aluminum holders that hung on the tree. I lit a few of them myself, carefully supervised. Can you imagine putting flames on a Christmas tree? Those candles only burned for 30 minutes or so before they were exhausted, and we stayed right by the tree until they were done – but still. Flames?!?!
Debbie and some local friends made two beautiful wreaths for our house last Friday. I keep forgetting to take photos, but finally here they are. The left-hand one is on our interior kitchen door, the right-hand one on our exterior front door.
Tuesday, December 12, 2017
Internet vulnerabilities...
Internet vulnerabilities... Over my career I've been responsible for running several Internet-facing datacenters. These all ran businesses that were utterly dependent on the Internet, so we paid a lot of attention to failure modes – ways that things could go wrong that would result in a business interruption. We eventually waded through enough data on actual failures that we could identify three primary concerns. Together these accounted for all but a tiny percentage of outages actually experienced by real datacenters. In order, these were (ten years ago; things may have changed):
- Backhoes. Most datacenters are connected to the Internet by just one or two fiber-optic connections. The most common cause of an Internet outage in a datacenter is a backhoe cutting through one or both of these connections. Often the failover to the backup connection is inadequately tested, and cutting one cable results in an outage. Also, all too commonly both connections run in the same underground route, and a single backhoe swipe can sever them both.
- Undersea or buried backhaul connections. That's what this article is all about, focusing on undersea cables. Buried cables on land are, if anything, even more vulnerable – there are hundreds of miles of them running along Interstate highways and railroad right-of-ways that have nobody guarding them. A bad actor with a backhoe could sever one in minutes. A single cable cut wouldn't severely impact the Internet – but cut several carefully chosen cables at once and you could. This sort of attack is within the capability of any but the most feeble American adversaries, and requires minimal cleverness. Detailed information like this is readily available to anyone.
- NAPs and MAEs. Network Access Points and Metropolitan Area Exchanges are a largely American phenomenon. These are the places where major customers connect to the Internet, and where various Internet carriers interconnect with each other. There are a relatively small number of these, and while they have some security they are not secure against a determined military attack – and certainly not against an artillery or rocket attack. If you were a well-funded adversary to America, and you wanted to maximize your impact on American commerce and communications ... these would be obvious targets.
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