Meta has made significant advancements in improving the quality of international calls across its platforms, including WhatsApp, Messenger, and Instagram. By redesigning their routing architecture and implementing cross relay routing, they have effectively reduced latency, improved bandwidth, and minimized packet loss, resulting in a better calling experience for users worldwide.
In the realm of real-time communication, the quality of international calls has often lagged behind the advancements in cost reduction. With the rise of calling apps like WhatsApp, Messenger, and Instagram, international calls have become more accessible, with one in five calls made on these platforms being international. However, the quality of these calls remains a challenge, with users rating international calls 20% more negatively than local calls. In this blog post, we will explore the technical challenges of international calls and the innovative solutions developed by Meta to enhance call quality.
Reflecting on the past, the experience of making international calls was often fraught with high costs and poor quality. Users would find themselves crammed into public phone booths, watching the cost of the call tick away while struggling to hear distant voices. Today, the landscape has changed dramatically, allowing users to connect with anyone around the globe at little to no cost. Despite this progress, the focus on improving call quality has not kept pace.
International calls face unique technical challenges that contribute to their lower quality:
In response to these challenges, Meta has invested significantly in improving international call quality. This effort has led to substantial advancements in reducing network latency, improving bit rates, and minimizing video freezes. The following sections will delve into the architecture of calling systems and the innovative changes implemented to enhance international call quality.
Calls consist primarily of audio and video packets exchanged between users. However, many devices are behind routers or network elements, necessitating a calling relay to facilitate communication. This relay acts as a proxy, forwarding media packets between users. The relay's position allows it to play a crucial role in improving call quality by managing packet loss and congestion.
Smart relays can significantly reduce packet loss by intercepting negative acknowledgments (NACKs) and retransmitting lost packets. This process can halve the retransmission time, enhancing the overall call experience. However, international calls introduce additional complexities due to the increased distance between users, making it more challenging to react to network conditions.
To address the challenges of international calls, Meta has implemented a new routing architecture known as cross relay routing. This approach involves using two relays instead of one, strategically chosen based on their proximity to each user.
Group calls introduce additional complexities, such as increased congestion and varying network conditions among users. Meta's architecture adapts to these challenges by assigning multiple local relays to a call, allowing for more efficient congestion control and better overall call quality.
Meta's new architecture has shown statistically significant improvements in call quality metrics across its platforms. Key results include:
Looking ahead, Meta plans to refine its congestion control algorithms and enhance the security of cross relay traffic. The goal remains clear: to continue improving the quality of international calls and connect users around the world more effectively.
Meta's commitment to enhancing international call quality through innovative architectural changes demonstrates the importance of adapting technology to meet user needs. By addressing the unique challenges of international communication, Meta is paving the way for a more connected world, ensuring that users can enjoy high-quality conversations regardless of distance.
