Posts by Alan Brown

Russia threatens to set up its 'own internet' with China, India and pals – let's take a closer look

Re: They are obliged by law to do that

"the thirteen root servers"

Have you ever looked at the A records for "The thirteen root servers" ?

There are a LOT more than 13

"They're only going to be bothered about what comes in, less so with what traffic leaves."

They are to a point. One of the advantages of controlling the DNS is that you can make all those pesky VPN sites go away.

Re: The headline got my hopes up

"5-strikes-and-you're-out"

Take a look at the names they use. If they don't exist in your password file there's no harm whatsoever in making it one strike if they're attempted. (likewise, root, oper, sysman, toor, postmaster, etc)

Someone missed an important point

Those "alternate roots" are proposed as only accessible by BRICS countries.

It's a hop skip and jump to legislating that residents of these countries are only _allowed_ to use those alternate roots and to enforce that by forcing ISPs to divert port 53 and 5353 traffic to "approved" nameservers.

UK government bans all Russian anti-virus software from Secret-rated systems

Re: Jet Engine

"American military supremacy is based on money"

Actually, it was based on sheer numbers and production capabilities, They've rather painted themselves in to a very expensive corner of late.

Re: "Hopefully, those OS makers never come up with the idea of secure-by-design systems,"

"Which version of Windows was supposed to be a from-the-ground-up redesign"

I'll go one better.

Which version of BIND was supposed to be a from-the-ground-up redesign?

Re: Further sanctions

"It is not sanctions. It is treating the other side as an adversary which UK never ever stopped."

Nations do not have allies or adversaries. They have interests - Dr Kissinger pointed that out 45 years ago and anyone (or nation) which loses sight of that fundamental truth is bound to have a bad time sooner or later.

Just as the USA spies on everyone in the EU, do you really think that the UK isn't also doing it? Especially to the USA?

The fundamental issue is that Kaspersky detected malware on a PC - which is correct as it was malware. That malware was in a zip, so the zip was uploaded for analysis - which is only done if the user has explicitly opted into that facility. The zip happened to contain the source code for the malware.

The fact that the malware was written by the NSA and was illegally taken out of the faciility by someone who should know better makes no difference to the fact that the software was WORKING AS DESIGNED.

As for how the Russian govt got hold of it: Probably the same way that the NSA and GCHQ do - with massive snoop farms. I'm willing to bet that the suspect file uploads weren't done over https, nor were the files encrypted first using 2-key crypto (Something I bet Kaspersky is now doing)

One may suspect that the GCHQ directive is a tacit admission that they're also in the business of writing targetted malware.

Re: I guess NOFORN doesn't apply anymore?

"Wikipedia is about as reliable on contentious subjects as I am, and I don't trust myself an inch."

That notwithstanding, the Internet Research Agency has been traced a number of times back into Russian netspace and it's fairly clear they're a government disinformation outfit. If you think they're the only government with one of these, you're dreaming. The rest are simply more subtle.

Ofcom proposes ways to stop BT undercutting broadband rivals

Re: If BT can lower their prices........

It's hard to compare rail with telecoms.

The nationalised BR at its core still had the mindset of the private companies which preceeded it and treated "opposition" lines accordingly when they gained control of them (retaliation and revenge), instead of treating them as assets to be used appropriately. This is why the Midland Mainline was torn up and the rights-of-way sold off, which in turn is leading to so many problems with capacity today.

This problem went right on up until the time when it was reprivatised, at which time many of the old management which still dated back to those days was removed. The politics of the original companies still rings throughout the industry - one example being HS2, which for some obscure reason is being built in one direction from London northwards over a 25 year period instead of from Birmingham North/south Manchester north/south/ etc over a period of less than 10 (Lest you think this would be pie in the sky it's EXACTLY how the Eurostar/TGV route was built from Brussels to Amsterdam. I was living in Rotterdam at the time and it was interesting to see how the works proceeded in each direction until they linked up.)

Re: If BT can lower their prices........

"some other altnets are now complaining that that will deter their plans to build new nets as they won’t get their money back"

More to the point, based on past form, as soon as XYZ altnet announces plans to provide commercial broadband in any given village within 3 months after laying in the comms links and running tests to ensure every house can be covered, BT tells Openreach to suddenly decide it's economic to provide xDSL after all and sends a team of 500 people out to doorstep every house and get signups for contracts with BT broadband services.

When the Altnet then tries to get people who've expressed interest to actually sign a contract, they find that "Oh, we've signed a contract with BT and they've promised installation within a month"

BT then sit back knowing they've nobbled the altnet and can take as long as they like to actually _install_ that broadband - in Cranleigh the actual installation took more than 2 years and it was about 3 before any connections went live, with large portions of the village taking 6+ years to get connected.

And of course to do this kind of tiger-team installation takes Openreach away from the areas where it's being paid by the government to roll out broadband, so things get delayed there too.

THAT is the kind of anticompetitive behaviour that BT is getting away with.

Re: How about opening up Virginmedia's network

Unlike BT, Virgin's network wasn't rolled out using huge amounts of government funding.

Furthermore, Virgin and haven't been taking large government contracts over the last 2 decades to rollout broadband and then failing to actually do what they were contracted to do.

As long as...

BT is operating in both retail AND as a wholesale monopolist, it has an opportunity to game the market - and it does with unbridled enthusiasm.

The ONLY long-term fix for this mess is to fully split off Openreach and the lines side of the company into separate operations.

IE: Separate shares, board of directors and offices - and provisions in place to prevent "capture" of the wholesale company by any entity - it was done that way in New Zealand precisely _because_ of the way that BT and Openreach were documented as abusing the market and has been a sucess,

BT is terrified of this option because a separated Openreach/lines company is has a lot of opportunities for extra sales/income and an increase in its credit rating, whilst the retail/wholesale side would immediately face credit downgrades and sales losses.

Yes I know they keep FUDing that it's the other way around, but that's the same FUD Telecom New Zealand used and were proven 100% wrong - particularly on the credit rating side. The old Telco is looking increasingly shaky whilst the lines company is doing quite well thankyouverymuch.

The interesting part to glean from the New Zealand story is that as soon as the dead hand of anti-competiitive head office was taken off the handbrake, the NZ lines company immediately set out selling its services to all comers - particularly the companies which the old Telco regarded as direct competition and refused to have anything to do with. It went from being difficult to deal with ti actively selling itself and the effect on the NZ market was electrifying - taking the country from what was regarded as a "Hostile telecommunications environment" to one of the most competitive in the world - and fibre is being rolled out by simple dint of the fact that it;'s chepaer to install and cheaper to maintain. (Regulatory pricing favours fibre, but it and copper both pay their own way)

Guilty: NSA bloke who took home exploits at the heart of Kaspersky antivirus slurp row

Re: Stealing, really?

"When virus protection does what it's _designed to do_ it's not stealing and I bet there's mention of that in the EULA, so totally legal too."

It's even an option in the control panel of the software.

User dialled his PC into a permanent state of 'Brown Alert'

Re: Brownouts

"CRT screens to be used well past their sell-by date such that a dim screen was "fixed" by adjusting the HT voltage up a bit."

Which was ok until they caught fire due to to the tweaked HT causing a breakdown or the grime (or a combination of both)

I saw a couple of results of this mentality. It usually cost a lot more than simply replacing the CRT in the first place.

Re: Brownouts

"standardised desks forcing me into a posture that my back couldn't cope with."

That's an easy one. HSE complaint and $LARGE_FINE

Re: Out of paper

"I managed to not scratch the fuser roller un-jamming the thing, thankfully, because repairing that would not have been a warranty issue."

There are arguably good reasons for allowing that to become "Needs repair - and not under warranty" issue.

The single fastest way for people to learn lessons is when it directly affects their wallet.

Re: 2 Keyboards...

"They were supposed to have different desktop colours and a big "production system" watermark on the live system "

I always liked the way that OS/2 had a red background covered in bombs when you were logged in as admin.

Subtle but effective.

Re: Unplugged cable

(USB in rj45)

Yes but when it didn't work, you actually checked why and fixed it.

Now, how does a user manage to put a USB plug into an eSATA socket?

Re: So let's thanks technology...

"'It's the wild colour scheme that freaks me out,' said Zaphod, whose love affair with the ship had lasted almost three minutes into the flight. 'Every time you try and operate these weird black controls that are labeled in black on a black background, a little black light lights up in black to let you know you've done it.'"

US credit repair biz damages own security: 111GB of personal info exposed in S3 blunder

Re: Capone would be proud of this lot

"Continuous harrassment on top, but as I said, they ignore court orders."

Too bad you can't go back to the court with the evidence and file a contempt motion.

Judges tend to dislike being ignored.

156K spam text-sending firm to ICO: It wasn't us, Commissioner

Re: issued vs collected

"The company directors need to be made personally responsible"

Directors already are, _if_ someone wants to push the point. Limited liability refers to the financial responsiibilities of _SHAREHOLDERS_, not what directors might incur due to reckless/illegal activities.

Re: Call me Mystic Meg

"Followed closely by:"

Followed closely by a complaint to companies house about phoenixing companies avoiding fines for illegal activities.

There are already laws on the books for this kind of thing and the ICO have been using them to prevent liquidations proceeding.

"YES! Fine the companies that the spam is advertising for! "

That's exactly what the USA did in the Telephone Comsumer Protection Act of 1994 - except they made it trivial for the _victims_ to sue the spammer and advertiser in small claims court. (Joint and several liability)

The resulting liabilities put a large dent in unwanted phone marketing.

The statutory damages aren't large - only $500 per call, tripled for wilful breaches such as calling TPS-registsred numbers or withholding callerID, etc. But they don't need to be. If you're a business, imagine the impact of having to attend 20-50 small claims court hearings for this. Then imagine the "wee chat" your liability insurer is going to have about renewing your policy and next year's premiums - even if they decline to pay out because what was done was explicitly illegal activity.

Re: 30p/text

> what if the offending company is counting "fines" as part of its "cost of spamming people"

They are. That's why having a right of private action and statutory damages is so important.

It means that rather than getting a token slap on the wrist, they face the very real risk of being sued into non-existence by the people they've annoyed. The death of 1 million papercuts.

Dark fibre arts: Ofcom is determined to open up BT's network

"But maybe their objection is that what's source for the goose is source for the gander. "

Unlike BT's network, Virgin and Cityfibre weren't built with masses of government money, and nor have they been expanded using massive government grants given for the purpose.

In any case all that's needed is an operational split and requirement to treat all players the same. Openreach can still stay as a for-profit company. The first thing it would do as a non-BT controlled outfit would be to make offers to provide service to Virgin/Cityfibre etc or buy them out to get access to _their_ ducts.

Re: The consumer would like some of Ofcom's attention too

"Which of course, work really reliably if the power goes off.."

Mine works very reliably for about 12 hours with a small gel battery slung under it. Said battery has an expected life of decades if treated properly (modern charging kit can treat AGM batteries _very_ carefully)

Do your cordless phones work when the power goes off? A lot of consumers don't HAVE wired phones anymore.

Re: The consumer would like some of Ofcom's attention too

"Enough(ish) duct was built to run copper from exchange to homes."

There is NO reason whatsoever why the same cabinets which currently do FTTC can't also be voice concentrators and all that copper replaced with a couple of fibres back to the exchange and then broken out into BT/LLU providers there in exactly the same way that is done with FTTC

It's an option on the equipment BT's using - they choose not to do so. The actual cost of doing it the current way is effectively higher than replacing cabinet to exchange trunks, as the copper extracted is saleable and the longer the copper line, the more faults there are (most trunks are decades old and in some state of rot). The primary reason for continuing with the status quo is that it allows BT to maintain their monopolies.

Re: The consumer would like some of Ofcom's attention too

"And what does your router plug into?"

In most cases, GPON.

Re: Seems bizarre to me...then I'll try and explain

"The other thing that is at stake here is the BT Group pension fund liabilities. "

This bogeyman was raised to try and prevent Telecom NZ being broken up too.

The vast majority of the pensions liability falls in the lineside company (openreach) and as event have proven that is the part which has the best prognosis for being in rude health as a result of any split.

Why? Things like this: "Psst, hey Virgin, wanna run your fibres in our ducts? Pay us and you can! Wanna run cabling to all those streets where you don't provide Cable TV in our ducts? No problem! We've got the ducts and you've got the demand. Let's deal!"

Re: Seems bizarre to me...

When you have an incombent monopoly in the supply side which ALSO runs retail operations, you have a situation that's ripe for abuse, even when equal access for allcomers is mandated.

All that's happened so far is that Openreach are at arm's length. The undue influence of BT and their amazingly one-sided contracts continues.

The retail/wholesale and outdoor plant sides need to be entirely separated with separate shares, boards and offices. That's the scenario BT is terrified of - because as New Zealand proved, despite all the rhetoric and FUD, it's Openreach which is the commercial and financial core of the business and the part that lenders like to see(*). The retail/wholesale parts are extremely likely to whither if removed from their cash cow.

(*) Within months of Telecom New Zealand being broken up, lenders upgraded the credit rating of the lines company and DOWNgraded the credit rating of the remaining telco. Obtaining financing for expansion and fibre rollouts has proven to be simple and without the dead hand of Head Office stifling competition, equal access was easy to do. Everyone was happy except the former Telecom NZ telco, which whined that the access charges were too high(*) and it couldn't possibly pay them. They didn't get much sympathy

(*) line charges are regulated by the NZ ministry of commerce, originally based on figures supplied by Telecom NZ stating its operating costs. These turned out to be vastly overblown despite charges being less than half the previous monopoly company rate so everyone else who'd been paying much higher fees was surprised when Spark (Former TNZ) started whining that the rates were too high.

UK emergency crews get 4G smartmobes as monkeys attempt to emerge from Reg's butt

Re: Not only text messages on new years eve

Text messages are a tiny load on the system. With the advent of 4G, so is voice as you're no longer having to rely on TDM channels carrying mostly silence.

7/7 was pre-4G and for the most part the load was on the 2G network as the 3G network was immature. 2G being TDM gets overloaded extremely quickly and you can't just dial down QoS.

Open-source storage that doesn't suck? Our man tries to break TrueNAS

Re: Is ZFS hard - or just a bit different?

"Different"

The primary design ethos of ZFS is "Disks are crap. Deal with it" - instead of trying to deal with issues by layering lots of expensive redundancy all over the place and taking a big hit if a drive fails, it's designed around the _expectation_ that disks are cheap will fail and performance shouldn't suffer.

Vendors tend to package enterprise drives with ZFS but the actual design is intended to take advantage of consumer-grade drives. My test system uses a mixture of WD REDs and Seagate NAS drives, but it originally had WD greens in it (they were crap and all failed as did every single ST2000-DM series drive but no data was ever lost)

The advantages:

1: It detects and fixes silent ECC fails on the fly (and pushes the fix back to disk) - this is important because the standard error rate for disks will result in 1 bad sector slipping past ECC checking about every 44TB read off a drive.

2: There's no regular downtime needed for FSCK - scrubbing is done on the fly (a huge advantage when you have hundreds of TB of FSes)

3: RAIDZ3 - yes, 3 parity disks. With large arrays comes the increased risk of multiple drive failures during a RAID rebuild. We've lost RAID6 arrays in the past and whilst you can restore from tape the downtime is still a pain in the arse. My test 32TB array (2TB drives) has been rebuilt on the fly a large number of times and some of the drives are over 7 years old. It's still to lose any data,

4: Simpler hardware requirements. You don't need expensive RAID hardware (in fact it's a nuisance). ZFS talks directly to the drives and expects to be able to do so - this is where a number of "ZFS" vendors have badly cocked up what they're offering, crippling performance and reliability.

The money saved on HW raid controllers should be put into memory. You'd be surprised now many vendors are flogging multi-hundred TB systems with only 8 or 16GB ram. The more memory you can feed into a ZFS system the better it will perform - you need 1GB/TB up to about 50TB and that can be relaxed to about 0.5GB/TB above that, but more is better. Dedupe will massively increase both CPU and memory requirements and for most uses is not worth enabling (it's great in things like document stores or mail spools/IMAP stores)

5: Read caching (ARC and L2ARC) - this is relatively intelligent. Metadata (directories) are preferentially cached. Large files and sequentially read ones are usually not - preference is given to small files read often, to minimize headseek.

L2ARC allocations use ARC memory (pointers). If there is not enough ARC allocated, then L2ARC will not be used or may not be fully used.

6: Write caching. (ZIL and SLOG) - all pending writes are written to the ZIL first, then to the main array, then erased from the ZIL. The ZIL is part of the ZFS array unless you have a dedicated SLOG disk.

Important: SLOG and ZIL are NOT write caches. They're only there for crash recovery and are write-only under normal operation. ZFS keeps pending writes in memory and flushes them from there. The advantage of having the SLOG is that writes can be deferred until the disk is "quiet" and streamed out sequentially.

Caveats:

ZFS is designed to be autotuning, but some assumptions are wrong for dedicated systems (vs general purpose servers)

7: Tuning is important - Autotuning the ARC will result in only half the memory being allocated. In a dedicated ZFS server like TrueNAS, you can set this up around 80-90% (only about 3-4Gb is actually needed for the operating system) - and on top of that there's a tunable for how much metadata is cached (usually only about 20% of ARC). This can be wound up high on systems with lots of little files.

There are other tweaks you can make. The IOPS reported are pretty poor compared to the rusty arrays here.

The thing to bear in mind about ZFS is that it is entirely focussed around data integrity. Performance comes second. It will never be "blisteringly fast", but you can guarantee that the bits you put in are the same bits you get out.

That said, the ZFS arrays here are at least 10 times faster than equivalent hardware using EXT4/GFS/XFS filesystems when serving NFS and the caching (effectively a massive hybrid disk) means that head thrash on repeated hits to the same files is nonexistent. If you have a network /home this is an important feature.

I'm getting upwards of 400MB/s out of the TrueNAS when backing up, whilst still running fileserving operations and with access latencies staying low enough that people don't notice. When headthrash starts happening on any disk system, latencies go sky high extremely quickly so this is a critical parameter to keep an eye on.

Watch those graphs. If your ARC or L2ARC aren't growing to maximums then you're doing something wrong.

Re: @TP

The vendor in the UK is currently Storm.

I'm going to take credit for the fact that there's a UK vendor. We spent a lot of time working with ixSystems and local people (especially Frank Awuah) over the last 5 years to make this happen after having a torridly frustrating time dealing with UK vendors who were either pushing vastly overpriced or incredibly badly specced systems (frequently both).

The fact that there were no authorised sellers in the EU made obtaining the things difficult in an environment where "lack of local support" was one of the issues raised within the organisation. Frank was one of the people who saw the screaming need in the market and worked extremely hard to ensure that ixSystems products were more easily obtainable on this side of the Atlantic. (The only way to get the things previously was to import them yourself, with all the attendant hassles with customs clearance, etc etc)

Re: Confused

"Can someone please explain what the 10x factor for All-Flash Arrays is all about?"

Deduplication.

DO NOT DO THIS unless you are absolutely sure what you are doing and know your workload intimately. ZFS memory requirements go from a relatively linear 1GB per TB to an exponentially increasing demand as the storage space increases.

Re: no acceptable

"Taking an outage to reboot both controllers to solve mismatched software is not acceptable."

Nor is it necessary. I speak from experience here. The usual culprit for this kind of thing on a TrueNAS system is impatience as it can take quite a while for a freshly started node to be fully ready - which is why you have 2 nodes.

However in a controlled environment you don't have a bearded dragon chaos monkey pulling power mid-upgrade (remember: both nodes in one case means that if the power to the (redundant) PSUs goes off, then the whole system stops)

The system works off a set of static filesystem images in the boot media (usually satadoms). If an upgrade fails partway through (due to things like your chaos monkey pulling the power) then it will simply boot off the existing image (ie, last good snapshot). After the upgrade is complete and the new image is available on the boot media, a reboot will default into that image but you can fallback to any old software version you choose.

The boot media is a ZFS raid1 array. Configuration itself is held in a sqlite database and backed up in a number of places including a hidden area on the ZFS fileserving arrays. It's remarkably robust and whilst TrueNAS is not _aimed_ at enterprise users, they handle enterprise loads far better than our previous "enterprise" fileserving setup ever did at less than 1/4 the cost of something like a EMC solution - and for about 1/10 the cost of the equivalent Oracle ZFS-based solution (I'm including 5 year support on this.)

Just to give an idea about licensing costs: ixSystems sold us hardware and 5 year support on a 400TB system for less than Nexenta wanted to charge in first year software licensing charges alone (Nexenta don't sell systems, that's a seperate cost).

The problem with most ZFS vendors has been the fact that they've wanted extortionate figures for their product, or they've committed absolute build boners which crippled the system - the most common errors being putting hardware raid in front of the disks or insufficient memory in the server (You need at least 1GB per TB or performance will suffer badly). IxSystems pricing is _extremely_ reasonable and the quality of their support(*) makes most "enterprise" outfits look quite shoddy.

(*) If you need it. The odds are pretty good that unless you're doing cutting edge stuff, you won't need it.

Re: Fail over?

"Would you mind sharing some details and rough costs of your setup? "

TrueNAS systems are a dual head active/passive failover setup (2 complete computers in the one box). This functionality isn't in the FreeNAS systems and having messed around with HA failover for years I'd say that trying to roll your own is not for the faint hearted.

Failover takes under 30 seconds on the system here (400TB of rusty storage attached along with 3TB of pure flash array), which is short enough to not be noticeable even for linux systems using the fileserver as network /home - which is on the flash array. The rusty side here has just under 1TB of L2ARC, which mitigates head thrash when people start banging on the same files over and over for data processing.

Re: Fail over?

"What are the reasons that will trigger a fail-over, and do the heads have some watchdog to force a reboot/fail-over in case one head gets sick?"

Networking failure for the active head, watchdogs, etc.

Both heads live in the same case and there's an internal networking setup as well as the externally facing stuff. It works extremely well in my experience.

Twitter's fight to kill Uncle Sam's censorship of spying numbers edges closer to victory

Re: This is not democracy

The USA is heavily propagandised about being "the land of the free" and "democratic", but the reality is that it doesn't rate highly for either.

It's out of the top 10 for almost every freedom index and down at #39 or so for human rights, whilst on the "democracy" front, thanks to the massive levels of institutionalised corruption it's bubbling around the levels of 3rd world dictatorships and kleptocracies,

As a government agency you can get away with nearly anything in the USA as long as you keep painting anyone who calls you out on it as "unamerican" - kneejerk hypernationalism will take care of the rest.

High-freq trade biz sues transatlantic ISP for alleged spiteful cable cut

Re: High-frequency trading companies = parasites

" Without HFTs you would either have to go to Market A yourself, wait until Market B has an object for sale, or pay someone to bring the object from Market A to Market B."

Except that most of them don't. They buy and sell on the same boards and classic HFT behaviour is to swoop in as your'e executing a stock trade, jack the price up and have you pay a slightly higher figure for the privilege of not being faster than they are.

Worse, most of them do it by taking out options, so they don't actually expose themselves to much risk if you cancel your purchase - the options simply lapse instead of leaving them holding shares they can no longer make 0.0001 on by simply having intercepted your trade.

Re: High-frequency trading companies = parasites

" you might like AMD because you think Intel needs competition so they don't become a complete monopoly in x86 CPUs, but that doesn't mean you should buy AMD shares unless you don't care about making money."

In this kind of case you might well buy AMD shares in order to stave off an abusive monopoly which would end up costing more than the value of the AMD shares.

As for HFT (and day trading in general). it's damaging to the stability of the markets and should be banned.

At _best_ it's a form of rent seeking behaviour.

SpaceX 'raises' an extra 100 million bucks to get His Muskiness to Mars

Re: Andrew Silver, this is article is low effort trolling.

"Long way to go until it gets comparable to the village bus "

On the other hand, many other russian/soviet designs haven't been as successful. *ahem*N1*ahem*

The reason the russians keep coming back to Soyuz is because whenever they try anything else, it breaks - and quite frankly the village bus might be good enough to get babushka and her family to market, but it's a bit wheezy even then and not big enough to move the local football team and their hangers-on there, let alone onwards to where they really want to go - the pitch in the next town to play the neighbouring village team.

Rolls-Royce, Airbus, Siemens tease electric flight engine project

Re: Advantages

The shorthaul aircraft market is booming at the moment. The problem is that this is also a prime target for being eaten by electric high speed rail as fuel prices go back up to the levels they "should" be (about $200/bbl)

Increasing oil costs and increasing pressure to decrease carbon emissions is going to push things like hyperloop closer to reality for passenger transport and even make the Silk Road Rail routes more practical than ships, despite the incredibly low cost per box of moving freight on a post-panamax boat.

I wouldn't be at all surprised to see a Bering Strait rail tunnel for freight. The geology is more than suitable, what holds it back is politics and routing on the north american side.

Re: Advantages

Flying nuclear reactors are a non-starter. The USA tests showed that by the time you added enough shielding so the crew wasn't killed, you had no payload. The Soviets just radiated their crews, who didn't last long.

HOWEVER, the aircraft nuclear reactor research program begat the Oak Ridge Experimental molten salt reactor and these run hot enough to drive a Haber process efficiently enough to make hydrogen and then tack on a few carbon atoms for stability/handlability (ie, synthetic jet fuel).

Which means in a roundabout way you _CAN_ have a nuclear powered aircraft.

Re: Greenwash?

Trijets were a pain in the arse to service due to the height of the rear engine above the ground.

In the case of the DC10/MD11 that was a _very_ long way above the ground and the L1011's inlet duct came with its own sets of problems whilst only lowering the engine a small amount and significantly increasing cabin noise at the rear of the plane.

The tristar was relatively sucessful because of its autoland and autopilot features, not the engine layout (and was nobbled by underpowered engines anyway - necessitating a 4th engine at the rear for takeoff on the later stretches)

Re: Advantages

"In aviation the real advantage of electic power will be a reduction noise espectially on take off and landing"

Turbofan cores are already remarkably quiet. The only way to make them quieter (and more efficient) is to spin the fans slower - which is why geared turbofans such as the LEAP are flavour of the decade and being fitted to newer airframes despite the weight and complexity of a planetary gearbox transmitting 50MW being fitted in front of the core.

Slower fans also mean wider chord blades are doable (quieter) and variable pitch fans become possible (even quieter, can be feathered in the event of a failure = greater range in the event of an engine failure AND can be reverse pitched, which means no more heavy and noisy thrust reversers, which means mroe range or more revenue capacity.)

Geared fans means that the rear turbine disc can be spun at a more efficient (higher) speed (the current speed is a compromise between efficiency of pickup and not spinning the fans too fast), which in urn means that a bunch of other optimisations can be made along the entire core, possibly including higher compression ratios and making the hot exhaust even quieter by extracting more energy from it.

_Everything_ about aviation propulsion is a compromise. Gas turbines are 20-30% less efficient than piston engines, but they're lighter, more powerful and far more reliable.

Re: Advantages

"The other option is to have enough battery capacity to allow flight to an emergency landing site "

EBOPS ?

Re: Advantages

"They can use a smaller generator and run it continuously at it's most efficient speed"

Aircraft engines are sized for this anyway. It might make sense to use one core to directly (or electrically) drive a fan in front whilst electrically driving another but that's the kind of added complexity you probably don't want on a wing (you'd need a 10-20MW generator on the back of the core) and putting the core inside the fuselage comes with a staggering set of negatives (the weight on the wing and positioning of the engines happens to be "just right" to keep flutter in check so major redesigns would be necessary and that's quite apart from losing space for revenue cargo and the added risks if there's a turbine failure)

One of the simplest ways of improving gas turbine efficiency both on AND off-max-load performance is to fit a recuperator but that's only ever done on Marine and land-based turbines (weight isn't the issue, they're bulky but not heavy) - because an aircraft engine is usually operated at full load for most of its cycle the recuperator doesn't get nearly as much benefit as in ground-based applications (especially boats, which seldom run at full power for prolonged periods.)

Whoosh, there it is: Toshiba bods say 14TB helium-filled disk is coming soon

Re: Need to check if it's any use for A/V storage

"Best use one of those directional network cables..."

For the ultimate in audio purity, a pair of garden hoses full of mercury is the ultimate best speaker wire. It's even better than long crystal copper and allows you to hear every nuance of the performance including that mosquito farting beside the timpanis during the intermezzo.

Re: RE: RAID re-builds

"I am not so sure that I would want to chance re-building a 14TB RAID array."

I have a 32TB one at home and multiple 300TB ones at work. Raidz3 means that they're statistically very unlikely to suffer drive failure during rebuilds (and I test that regularly as part of my operating paranoia)

Re: Helium?

"I wonder how long mass produced HDDs will keep the helium in for?"

"At least the warranty period"

"And what will be the consequence of it leaking out?"

Increasing power consumption, slower access and eventually read failures due to the fly height of the heads being too high for reliable data.