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Articles like this are why people think the cloud is oversold

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The cloud can solve many problems, and is rightly seen as one of the easiest ways to launch web services. But it isn’t magical, and articles like this  are why people think the cloud is being oversold: The cloud is not the solution to finding missing Malaysian flight 370:

But if MH370 had been fitted with technology that made use of the cloud it may never have been lost in the first place. The cloud is a cluster of computers that provides reliable computing and storage as a service to large numbers of requests from computers with limited capabilities, such as those on board a plane or inside a mobile phone.

What the author says is really “planes should dial-back to a server with their telemetry”

This may be true, but as a comment on the article points out: that doesn’t need the cloud.

It needs a server in a data-centre. Now you may choose to deploy that server as a virtualised box in the cloud, but this is not an application where you need the main virtues of cloud type platforms.

Over and above machine virtualisation, I tend to think about ‘cloud’ meaning some combination of these  things:

  1. You scale your resources when you need them, not ahead of time. The best example of this is storage: you don’t have to pre-size your storage allocation in Amazon or Azure. 1
  2. Your application is making use of the two main scaling patterns, incoming load balancers2 and asynchronous message passing3, to dynamically change the amount of processing capacity that you have.
  3. Not a technical thing, but your costs should be scaling in line with your usage. Having the incentive to save money by doing as little as possible when you’re idle will encourage you to properly scale.
  4. You start treating your servers as livestock and not pets. If  virtualisation separates your instances from the physical hardware,  cloud deployment should separate your application from the instances.
  5. Your deployment should be cheap. It should take minutes, and be painless, and shouldn’t make your ops team bite their nails in fear. It needs to be a routine, accepted, automated process. This also requires you to have your config held in more durable places than a file on an instance, which could disappear at any moment.

The dial-back type solution that could help us find missing planes doesn’t really need many of these characteristics. The data formats would be relatively static, and the loading wouldn’t peak to such levels that you needed to place it all behind a massive loadbalancer. You’d care about reliability, but I don’t see masses of room for flexing things here.

Yes dial-back is a good opportunity to improve visibility (the ACARS data from Air France flight 440 provided a  trace of the accident), but what really could have helped us in the case of Malaysian 370, would have been that something had continued to report back position information after ACARS was disabled.

We don’t know if ACARS was disabled manually by the flight crew, or by a result of electrical systems being de-powered due to a fire. We do know the Inmarsat satellite modem was still functioning for some time, and responded to a network level ping. This only gave us a confirmation that the modem was still in range of a satellite beam, and unfortunately it was a large satellite beam which covers a wide area.

Had the plane been fitted with a newer Inmarsat system, it would have been connecting to a satellite beams with smaller footprints, which could have narrowed the search area.

What might have helped  would have been if there was another GPS receiver integrated with the satellite modem, so that even without the main ACARS system, at least position could still be reported.

That isn’t in the cloud however, that’s on the plane.

Better reporting back could have helped the investigators here, but no, that is not another solution in search of “the cloud”.

Footnotes:
  1. Much to the cheers of capacity planners
  2. When more people hit your website, you launch more servers
  3. Instead of doing an operation when a request comes in, you put it on a queue. When the queues start growing too big, you start additional instances

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