Real-Time Communications at Scale

For every successful technology, there is a moment where its time comes. Something happens, usually external, to catalyze it — shifting it from being a good idea with promise, to a reality that we can’t imagine living without. Perhaps the best recent example was what happened to the cloud as a result of the introduction of the iPhone in 2007. Smartphones created a huge addressable market for small developers; and even big developers found their customer base could explode in a way that they couldn’t handle without access to public cloud infrastructure. Both wanted to be able to focus on building amazing applications, without having to worry about what lay underneath.

Last year, during the outbreak of COVID-19, a similar moment happened to real time communication. Being able to communicate is the lifeblood of any organization. Before 2020, much of it happened in meeting rooms in offices all around the world. But in March last year — that changed dramatically. Those meeting rooms suddenly were emptied. Fast-forward 18 months, and that massive shift in how we work has persisted.

While, undoubtedly, many organizations would not have been able to get by without the likes of Slack, Zoom and Teams as real time collaboration tools, we think today’s iteration of communication tools is just the tip of the iceberg. Looking around, it’s hard to escape the feeling there is going to be an explosion in innovation that is about to take place to enable organizations to communicate in a remote, or at least hybrid, world.

With this in mind, today we’re excited to be introducing Cloudflare’s Real Time Communications platform. This is a new suite of products designed to help you build the next generation of real-time, interactive applications. Whether it’s one-to-one video calling, group audio or video-conferencing, the demand for real-time communications only continues to grow.

Running a reliable and scalable real-time communications platform requires building out a large-scale network. You need to get your network edge within milliseconds of your users in multiple geographies to make sure everyone can always connect with low latency, low packet loss and low jitter. A backbone to route around Internet traffic jams. Infrastructure that can efficiently scale to serve thousands of participants at once. And then you need to deploy media servers, write business logic, manage multiple client platforms, and keep it all running smoothly. We think we can help with this.

Launching today, you will be able to leverage Cloudflare’s global edge network to improve connectivity for any existing WebRTC-based video and audio application, with what we’re calling “WebRTC Components”.  This includes scaling to (tens of) thousands of participants, leveraging our DDoS mitigation to protect your services from attacks, and enforce IP and ASN-based access policies in just a few clicks.

Real-time typically refers to communication that happens in under 500ms: that is, as fast as packets can traverse the fibre optic networks that connect the world together. In 2021, most real-time audio and video applications use WebRTC, a set of open standards and browser APIs that define how to connect, secure, and transfer both media and data over UDP. It was designed to bring better, more flexible bi-directional communication when compared to the primary browser-based communication protocol we rely on today, HTTP. And because WebRTC is supported in the browser, it means that users don’t need custom clients, nor do developers need to build them: all they need is a browser.

Importantly, we’ve seen the need for reliable, real-time communication across time-zones and geographies increase dramatically, as organizations change the way they work (yes, including us).

So where is real-time important in practice?

• One-to-one calls (think FaceTime). We’re used to almost instantaneous communication over traditional telephone lines, and there’s no reason for us to head backwards.

• Group calling and conferencing (Zoom or Google Meet), where even just a few seconds of delay results in everyone talking over each other.

• Social video, gaming and sports. You don’t want to be 10 seconds behind the action or miss that key moment in a game because the stream dropped a few frames or decided to buffer.

• Interactive applications: from 3D modeling in the browser, Augmented Reality on your phone, and even game streaming need to be in real-time.

We believe that we’ve only collectively scratched the surface when it comes to real-time applications — and part of that is because scaling real-time applications to even thousands of users requires new infrastructure paradigms and demands more from the network than traditional HTTP-based communication.

Today, we’re launching our closed beta WebRTC Components, allowing teams running centralized WebRTC TURN servers to offload it to Cloudflare’s distributed, global network and improve reliability, scale to more users, and spend less time managing infrastructure.

TURN, or Traversal Using Relays Around NAT (Network Address Translation), was designed to navigate the practical shortcomings of WebRTC’s peer-to-peer origins. WebRTC was (and is!) a peer-to-peer technology, but in practice, establishing reliable peer-to-peer connections remains hard due to Carrier-Grade NAT, corporate NATs and firewalls. Further, each peer is limited by its own network connectivity — in a traditional peer-to-peer mesh, participants can quickly find their network connections saturated because they have to receive data from every other peer. In a mixed environment with different devices (mobile, desktops), networks (high-latency 3G through to fast fiber), scaling to more than a handful of peers becomes extremely challenging.

Running a TURN service at the edge instead of your own infrastructure gets you a better connection. Cloudflare operates an anycast network spanning 250+ cities, meaning we’re very close to wherever your users are. This means that when users connect to Cloudflare’s TURN service, they get a really good connection to the Cloudflare network. Once it’s on there, we leverage our network and private backbone to get you superior connectivity, all the way back to the other user on the call.

But even better: stop worrying about scale. WebRTC infrastructure is notoriously difficult to scale: you need to make sure you have the right capacity in the right location. Cloudflare’s TURN service scales automatically and if you want more endpoints they’re just an API call away.

Of course WebRTC Components is built on the Cloudflare network, benefiting from the DDoS protection that it’s 100 Tbps network offers. From now on deploying scalable, secure, production-grade WebRTC relays globally is only a couple of API calls away.

But, as we like to say at Cloudflare: we’re just getting started. Managed, scalable TURN infrastructure is a critical building block to building real-time services for one-to-one and small group calling, especially for teams who have been managing their own infrastructure, but things become rapidly more complex when you start adding more participants.

Whether that’s managing the quality of the streams (“tracks”, in WebRTC parlance) each client is sending and receiving to keep call quality up, permissions systems to determine who can speak or broadcast in large-scale events, and/or building signalling infrastructure with support chat and interactivity on top of the media experience, one thing is clear: it there’s a lot to bite off.

With that in mind, here’s a sneak peek at where we’re headed:

• Developer-first APIs that abstract the need to manage and configure low-level infrastructure, authentication, authorization and participant permissions. Think in terms of your participants, rooms and channels, without having to learn the intricacies of ICE, peer connections and media tracks.

• Integration with Cloudflare for Teams to support organizational access policies: great for when your company town hall meetings are now conducted remotely.

• Making it easy to connect any input and output source, including broadcasting to traditional HTTP streaming clients and recording for on-demand playback with Stream Live, and ingesting from RTMP sources with Stream Connect, or future protocols such as WHIP.

• Embedded serverless capabilities via Cloudflare Workers, from triggering Workers on participant events (e.g. join, leave) through to building stateful chat and collaboration tools with Durable Objects and WebSockets.

… and this is just the beginning.

We’re also looking for ambitious engineers who want to play a role in building our RTC platform. If you’re an engineer interested in building the next generation of real-time, interactive applications, join us!

If you’re interested in working with us to help connect more of the world together, and are struggling with scaling your existing 1-to-1 real-time video & audio platform beyond a few hundred or thousand concurrent users, sign up for the closed beta of WebRTC Components. We’re especially interested in partnering with teams at the beginning of their real-time journeys and who are keen to iterate closely with us.