The Story of Siri

Photo by Omid Armin on Unsplash.

Deep-Dive Into the Most Popular AI-Assistant on the Planet

My journey started into tech with my very first PC — a 4th generation iPad, which I won in a contest at school in the 6th grade.

One of my earliest memories of that device was the time I asked Siri, “who is Steve Jobs?” just to see how it would respond. In fact, the year was 2013, and the former Apple CEO had passed away over a year ago.

But what happened next shocked me: I remember Siri bringing up the special page for “Remembering Steve” and I was floored by how thoughtful the creators of Siri must have been in their design.

Unfiltered access to tools like Siri changed the course of my life, so today I will attempt to show the technology behind how it works, and the impact it has on the planet.

Part 1: What is Siri Made Of?

With more than a billion users, chances are that readers are familiar with Siri — but makes the personal assistant work under the hood?

Hardware & The Siri Client

What Happens When You Say “Hey Siri” (Image: Siri Team, Apple Machine Learning)

Siri’s functionality makes direct use of Apple hardware. It all starts with the microphone. Taking the iPhone as an example, as the diagram above shows, Siri activates when users say “Hey Siri,” (Siri Team). The computer program that runs Siri on a customer’s device is called the “Siri Client”.

Software & Natural Language Processing

An example of what a Recurrent Neural Network, commonly used in Natural Language Processing, looks like. Image: Siri Team, Apple Machine Learning)

Once the device has listened to the user’s request, it is now time to figure out what they actually want. This is commonly performed through recurrent neural networks, a popular deep learning model that is used to bridge the gap between spoken words in human language, and instructions that Siri interprets using machine language. More generally, computer scientists call this area of artificial intelligence natural language processing (NLP).

The Server & Apple’s Data Centers

Apple’s Data Center in Sparks, Nevada (Image: David Calvert, WIRED

It is easy to miss, however there is a lot more to Siri than just what the user sees on their device. Once the Siri Client understands what the user needs, it sends a request to the Siri Server, to get whatever answer it deems useful. The Siri Server resides in the cloud. This is made by possible by data centers (Levy, WIRED), such as the one pictured above, which Apple operates in order to run the computers needed to host their online services.

Takeaways

In closing, Siri is made up of a combination of software, hardware, and the cloud. Once the response comes back from the Siri Server, the iconic voice of the Siri Client responds to the user through the speakers. This ends the user flow right back to where it began, between the user and their device.

Part 2: How Did Siri Come About?

Siri is a digital product built on top of many components. How are these pieces — some of which having a physical footprint on the planet — created and used by Apple?

The Manufacturing

A diagram illustrating Apple’s vision for a circular supply chain, which they have stated as their goal to reach sometime in the future. (“Material Impact Profiles”, Apple.com).

The devices that run Siri are the direct result of materials mined from the Earth. To prove this, Apple provides what it calls an “environmental report card” on its website for its most recent products. For example, the report card for an iPhone XR lists that it is made from 17 grams of aluminum, and 100% recycled tin (“iPhone XR Environmental Report”).

Further, Lisa Jackson — the VP of Environment, Policy & Social Initiatives at Apple, releases a company-wide environmental grade report annually. The statistics in this report tend to focus on improvements, such as Apple’s 100% carbon neutral corporate operations in 2019 (Jackson, Environmental Progress Report). The credibility of this report was assured independently by Apex and the Fraunhofer Institute.

While these reports do not include an exhaustive list of all the materials in their devices, Apple’s website does provide “Material Impact Profiles”, a PDF that lists about 45 elements on the Periodic Table which they are currently working to remove or reduce in order to reach a circular supply chain. The elements are displayed below:

Highlighted elements on the Periodic Table which Apple is focusing on, in order to reach a circular supply chain (“Material Impact Profiles”, Apple).

Distribution Across Devices

Apple installs Siri onto all their platforms, and their customers can use them across all the devices they buy.

Wouldn’t this give Apple the ability to collect massive amounts of personal voice data about its users? The answer is yes — however, Siri decreases the amount of data it sends to Apple greatly by using a privacy-promoting strategy called federated learning (Hao, “How Apple personalizes Siri”).

A diagram of how federated learning works. (A) the user’s machine learning model on-device does its own learning, (B) then it sends the result of that training to be collected with the output of other devices. © finally, these updates are combined to make a single update the machine learning model housed on the company server, so it can be sent out again across all the customers’ devices (“Federated Learning” Google AI Blog).

Federated learning is a technique for deploying AI in a way that emphasizes user privacy by maximizing on-device processing. Most companies that ship machine learning products improve them over time, as the models are exposed to more data. However, rather than send the users’ data to Apple’s server in order to improve Siri, a mini-version of Siri is installed on every device. This micro-Siri is what learns from the user’s data, allowing the device to send just the improvements to that model to Apple, which are associated with random identifiers and aggregated with the gains made by all the other devices (Bonawitz et al). Thus, Apple is able to continue making improvements to Siri based on the feedback from the crowd, while simultaneously reducing the chance of any individual’s data being exposed.

Takeaways

In this section, we have peeled back the layers behind Siri’s production. We saw how rare earth metals are used to manufacture the hardware, and how Apple distributes privacy-minded software for Siri to their users.

Part 3: Is Siri Sustainable?

At first glance, Siri seems to be the perfect product for sustainability — using it requires no additional hardware, nor does it add any physical waste when the user disposes of their device. Does this view hold true upon further inspection?

Energy Costs

A man walks through solar panels used to power Apple’s data center in Oregon (Jackson, Environmental Progress Report).

As a digital product, Siri’s main impact on the planet is the electricity used to create it. Apple reports that all of its operations are carbon neutral — this includes that the data centers that deploy Siri, and the stores that sell Siri all run on 100% renewable electricity (Jackson, Environmental Progress Report).

However, about half of Apple’s total carbon footprint comes from the electricity used in manufacturing (Apple). The most recent Environmental Report for the company shows a little over 70 of Apple’s suppliers have committed to using 100% renewable electricity as well (Jackson, Environmental Progress Report). This means Apple is not 100% carbon neutral yet, albeit it has made remarkable progress since reaching its peak carbon footprint in 2015.

Labor Practices

On the surface, Apple appears to have a stellar attitude towards workers. A quick scroll through Glassdoor will show the company has an average rating of 4.3 out of 5 stars (Reviewers at Apple), backed by more than 19,000 reviews by employees. But is that all there is to the picture?

Jenny Chan’s Dying for an iPhone (2020) reveals shocking details about the impact that the Siri manufacturer has upon factory workers in off-shore locations. The book focuses particularly on Foxconn, a Taiwanese manufacturer of iPhones and iPads who partners with Apple. Workers inside their Chinese factories report suffering under brutally long hours. They are exposed to the threats of violence, fire hazards, and metallic dust explosions to the point where some have even attempted suicide (Chan, Jenny, et al.). While Apple invests much in making sure its employees fare well, the making of products like Siri still leaves a damaging impact on workers elsewhere.

In Dying for an iPhone (2020), researchers from both the US and China team up to expose the hardships faced by Foxconn workers who help build Apple products (Chan, Jenny, et al.).

Summary and Closing

Siri is a miracle resulting from the productivity of modern energy systems and supply chains. Apple invests heavily in making sure their carbon footprint approaches carbon neutrality quickly, as well as reaching out to make their suppliers do so as well. The same can be said for their labor practices. While Apple clearly wins over their employees in terms of treatment, far more is yet to be done for workers abroad who indirectly suffer as a result of making the products that run Siri.

Works Cited

Because it’s always a good idea to fact-check!

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