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What Does It Take to Track a Million Cell Phones?

thehftguy.com

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Re: What Does It Take to Track a Million Cell Phones?

#61
post #59

I did the math a while back, don't have the notes at the moment, but scaling an AWS system I built enough to collect 600m points of data each minute and compute on data within 100ms and retain it for a few minutes would run a bit over $10k usd/mo to operate. I operated it at about 3m events/min with a good amount of compute per including ip to geo lookup... Zookeeper would be the only bottleneck in this case assuming…

Using AWS is the problem here, and that's why it's so expensive. You could do this on bare metal WAY faster and more efficiently, and then you own the hardware forever, for the price you paid to do it for a month with a third party. AWS does not scale this way, you can't just throw more resources at a problem and expect to be profitable.

Put everything in Google BigQuery or Google DataProc.

Cheaper than both and hardly any maintenance required.

Re: What Does It Take to Track a Million Cell Phones?

#62

Earlier quoted context omitted.

I have not written about it. Most of the difficulty and complexity, from my perspective, is in the data science and processing required to construct an accurate population model, which requires additional data sources beyond the mobile telemetry. I designed the custom database platforms (easy for me) underneath which supported the online data processing. It isn't that difficult technically, if you have experts doing…

I'm gonna take a wild guess, and say that the NSA has a monopoly on the talent for this field.

Most of this talent is in the private sector. Primarily around traffic.

Re: What Does It Take to Track a Million Cell Phones?

#63

Earlier quoted context omitted.

I have not written about it. Most of the difficulty and complexity, from my perspective, is in the data science and processing required to construct an accurate population model, which requires additional data sources beyond the mobile telemetry. I designed the custom database platforms (easy for me) underneath which supported the online data processing. It isn't that difficult technically, if you have experts doing…

I'm gonna take a wild guess, and say that the NSA has a monopoly on the talent for this field.

The handful of people I know that are real experts at the data science are all in the private sector.

Re: What Does It Take to Track a Million Cell Phones?

#64
post #59

I did the math a while back, don't have the notes at the moment, but scaling an AWS system I built enough to collect 600m points of data each minute and compute on data within 100ms and retain it for a few minutes would run a bit over $10k usd/mo to operate. I operated it at about 3m events/min with a good amount of compute per including ip to geo lookup... Zookeeper would be the only bottleneck in this case assuming…

Using AWS is the problem here, and that's why it's so expensive. You could do this on bare metal WAY faster and more efficiently, and then you own the hardware forever, for the price you paid to do it for a month with a third party. AWS does not scale this way, you can't just throw more resources at a problem and expect to be profitable.

Agreed it could be done cheaper over long term, just wanted to share about an actual prod system. This also had 3x replication via Kafka to avoid stampedes etc if anything failed and keep going with an at-least-once guarantee.

In my opinion tho, even that price point is pretty accessible to keep tabs on all citizens with that resolution which was my hypothetical case.

Re: What Does It Take to Track a Million Cell Phones?

#65
post #55

Earlier quoted context omitted.

I'm gonna take a wild guess, and say that the NSA has a monopoly on the talent for this field.

The Snowden leaks confirmed NSA has the ability to conduct co-traveler inference.[0] In other words: finding mobile devices proximate to a targeted mobile device, based on similar vectors. Perhaps even making associations in absence of targeting via patterns in device proximity over time. It probably gets real interesting when they're trying to distinguish between various modes of transit, such as a city bus, an Uber…

Graph reconstruction from space-time event data goes far beyond the above in terms of capability. You can infer relationships between people that never co-travel, infer that people have been places that are not in the event data, etc by stitching together large numbers of orthogonal event streams over long periods of time. It is straightforward to distinguish between various modes of transit analytically. The "metadata" that simply indicates an event in space-time is far more valuable analytically than the data because it is possible to reconstruct so much with it that isn't contained within the data per se.

I was doing all of this five years ago, the capability has been around for a while.

Re: What Does It Take to Track a Million Cell Phones?

#66

A: A deeply sociopathic mindset. See the requirements section for details.

I have no intention of contradicting that, but if so, that makes it all the more disturbing the organizations where this if not only standard operating procedure but just one tool among many similar ones.

Re: What Does It Take to Track a Million Cell Phones?

#67
post #55

Earlier quoted context omitted.

The Snowden leaks confirmed NSA has the ability to conduct co-traveler inference.[0] In other words: finding mobile devices proximate to a targeted mobile device, based on similar vectors. Perhaps even making associations in absence of targeting via patterns in device proximity over time. It probably gets real interesting when they're trying to distinguish between various modes of transit, such as a city bus, an Uber…

Graph reconstruction from space-time event data goes far beyond the above in terms of capability. You can infer relationships between people that never co-travel, infer that people have been places that are not in the event data, etc by stitching together large numbers of orthogonal event streams over long periods of time. It is straightforward to distinguish between various modes of transit analytically. The "metada…

Do you ever worry that this data might be used for bad purposes?

Re: What Does It Take to Track a Million Cell Phones?

#68

I've designed systems that do this on continental scales (i.e. hundreds of millions of cell phones simultaneously, in real-time). The devil is in the details and non-trivial; this is not a "an intern and 6 months" job. Mobile telemetry is not nearly as ideal in practice as assumed here and it typically takes a couple years to learn how to handle the numerous peculiar artifacts of that data that will damage the qualit…

> the numerous peculiar artifacts of that data that will damage the quality of a naive implementation.

Do you have examples (or a link/reference to something that has such examples) of those types of artifacts?

Re: What Does It Take to Track a Million Cell Phones?

#69

Earlier quoted context omitted.

Have you posted about this at length somewhere? If not, care to elaborate on what it took to design this system?

I have not written about it. Most of the difficulty and complexity, from my perspective, is in the data science and processing required to construct an accurate population model, which requires additional data sources beyond the mobile telemetry. I designed the custom database platforms (easy for me) underneath which supported the online data processing. It isn't that difficult technically, if you have experts doing…

> which requires additional data sources beyond the mobile telemetry.

So it really isn't technically difficult. It's just lacking in data?

In your original post, you made it seem like it was extremely difficult. From my perspective, it seems like child's play from a technical standpoint.

> It isn't that difficult technically, if you have experts doing it

But your top comment implied it was extremely technically difficult.

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