How Netflix Architecture Works: AWS & Open Connect CDN

Quick Answer: Netflix separates its control plane (AWS) from its data plane (Open Connect). Instead of streaming massive video files directly from AWS data centers, Netflix embeds custom hardware called Open Connect Appliances (OCAs) inside Internet Service Providers' networks. These local boxes pre-cache predicted content overnight, serving up to 70% of video traffic locally to reduce latency and ISP bandwidth costs.

When you press play on Netflix, you aren't streaming gigabytes of video data from an AWS data center halfway across the country. In fact, if Netflix attempted to route all its stream traffic directly through AWS, public cloud egress costs and internet exchange bottlenecks would render the business model unsustainable.

Here is a breakdown of how Netflix delivers petabytes of data seamlessly using a hybrid cloud and edge infrastructure.

How Does Netflix Architecture Separate Control Plane and Data Plane?

Netflix splits its system architecture into two distinct operational layers: AWS manages the control plane, while an in-house Content Delivery Network (CDN) called Open Connect handles the data plane. AWS handles lightweight API requests like user authentication, catalog browsing, and recommendations, while local Open Connect Appliances (OCAs) store and deliver actual video streams.

Think of AWS as a hotel's front desk and the Open Connect Appliance as the mini-fridge inside your guest room. You interact with the front desk to check in, get your room key, and request recommendations. However, when you want a bottle of water, you do not call the lobby to send someone up from the basement—you reach directly into the mini-fridge right next to you.

By isolating heavy payload delivery from core application logic, Netflix offloads massive bandwidth demands from public cloud providers. When a user hits play, AWS simply returns a manifest file containing the direct network address of the optimal local OCA.

System Component	Architectural Layer	Primary Responsibilities
AWS Cloud	Control Plane	User authentication, billing, search, UI rendering, recommendation engine
Open Connect Appliance (OCA)	Data Plane	Video chunk pre-caching, localized byte streaming, adaptive bitrate delivery

Why Do Internet Service Providers Allow Netflix Hardware in Their Data Centers?

Internet Service Providers (ISPs) host Netflix's custom hardware for free because it dramatically reduces their upstream bandwidth costs. Without local caching, thousands of subscribers watching the same high-definition release simultaneously would flood the ISP's internet exchange links with redundant data transfers.

Imagine a local coffee shop serving a crowd of 500 office workers every morning. Instead of sending 500 individual delivery drivers to a central bakery across town every few minutes, the bakery sends one bulk shipment to a storage rack inside the coffee shop before doors open.

For ISPs, transferring data across third-party backbones is expensive. Installing an OCA directly inside an ISP's central office transforms costly transit traffic into local network traffic. According to Netflix's figures, approximately 69% of their traffic in Central and Eastern Europe was served directly from inside ISP networks via these embedded boxes.

How Does Open Connect Pre-Cache Content Before You Press Play?

Open Connect Appliances pre-fill their local drives during off-peak hours using predictive machine learning models. Every night, typically around 2 AM local time, the appliances download the specific movies and show episodes that Netflix algorithms predict local subscribers will stream the next day.

Rather than reactively fetching a video file when a subscriber clicks play, the system operates proactively. If a popular series releases a new season, nearby OCAs have already fetched and assembled the encrypted media chunks over quiet overnight connections. By the time peak viewing hours arrive, the network load is already smoothed out, ensuring instant playback with minimal buffering.

Frequently Asked Questions

Does Netflix pay ISPs to host Open Connect Appliances?

No, Netflix provides Open Connect Appliances to qualified ISPs completely free of charge. ISPs host and power them voluntarily because the local caching saves them money on transit bandwidth costs.

What happens if a local Open Connect Appliance fails or lacks a requested title?

If a local appliance fails or does not contain the requested video file, the Netflix client automatically fails over to stream the content from a secondary regional Open Connect server located at a nearby Internet Exchange Point (IXP).

Why doesn't Netflix use commercial CDNs like Cloudflare or Fastly?

At Netflix's extreme scale, off-the-shelf CDNs are cost-prohibitive. Building custom, single-purpose hardware optimized purely for sequential video streaming allows Netflix to achieve significantly higher storage density and cost efficiency than general-purpose CDNs.