WhatsApp is one of the most popular messaging apps in the world, used by over 2 billion people across 180 countries. Since it handles billions of messages per day, WhatsApp requires a complex infrastructure of servers and data centers around the world to reliably deliver messages in real time. But which servers exactly does WhatsApp use to power its global service?
In this article, we’ll take a deep dive into the technical workings of WhatsApp’s server infrastructure. We’ll look at the different types of servers used by WhatsApp, where they are located, and how they work together to enable fast and seamless messaging capabilities. Whether you’re a tech enthusiast curious about WhatsApp’s backend or someone looking to better understand modern messaging infrastructure, this guide has you covered.
WhatsApp’s Core Infrastructure
WhatsApp’s core infrastructure consists of geographically distributed clusters of servers located in data centers around the world. Here are the key components:
Application Servers
Application servers handle the core messaging logic and run the WhatsApp software. They enable essential functions like:
– Managing user accounts and profiles
– Routing and processing messages between users
– Encrypting and decrypting messages end-to-end
– Interfacing with clients apps on users’ smartphones
WhatsApp operates thousands of application servers across different data center regions. Having many distributed servers allows them to scale messaging capacity and redundancy.
Media Servers
Media servers are dedicated to managing multimedia messaging like photos, videos, audio clips, documents and other non-text content. They handle:
– Processing and optimizing media uploads from users
– Transcoding media into compatible formats
– Storing media in cloud storage systems
– Delivering media to recipients efficiently
Media servers help provide a seamless multimedia messaging experience, especially for data-heavy content.
Database Servers
WhatsApp leverages database servers running SQL and NoSQL database systems to store and manage all user data and message data. This includes:
– User profiles, contact lists, preferences
– Message histories, timestamps, delivery statuses
– Group data like participants, names
– Media metadata like hashes, captions
By leveraging specialized database servers, WhatsApp can efficiently store and query massive volumes of data generated by billions of users.
Caching Servers
Caching servers help improve performance by storing frequently accessed data in memory for low latency lookups. WhatsApp uses caching heavily for data like:
– User avatars
– Frequently accessed media
– Message data for online users
– Cryptographic keys
Caching speeds up the retrieval of common data types and reduces load on databases.
Web Servers
To support WhatsApp’s web and desktop apps, WhatsApp employs web servers like Nginx and Apache. These servers enable browser-based WhatsApp clients to seamlessly access user data and messages through a REST API. The web servers authenticate users and proxy requests between browsers and the application servers.
Supporting Cloud Infrastructure
In addition to its core servers, WhatsApp relies on an extensive cloud infrastructure for services like:
Object Storage
WhatsApp stores billions of media files like photos, videos and documents in Amazon S3 and other object storage systems across its cloud providers. Object storage allows infinitely scalable and cost-efficient storage for large amounts of unstructured data.
Load Balancers
Global load balancing across data centers helps WhatsApp distribute traffic evenly to its servers. This maintains optimal performance and uptime for users. WhatsApp uses load balancers like AWS Elastic Load Balancing.
CDN
WhatsApp leverages content delivery networks (CDNs) like Fastly to cache media, deliver it quickly to users and reduce load on its servers. Major CDNs have points of presence near users for low latency.
DNS Servers
WhatsApp relies on managed DNS servers to allow clients worldwide to discover and connect to its servers using hostnames like whatsapp.com. This includes GeoDNS for localization.
SSH Bastions
WhatsApp engineers use SSH bastions as “jump boxes” to securely manage its servers without exposing them publicly. Bastions provide an access control layer and audit trail.
| Cloud Infrastructure | Key Providers |
|---|---|
| Object Storage | Amazon S3, Google Cloud Storage |
| Load Balancers | AWS ELB, GCP LB |
| CDN | Fastly, Akamai |
| DNS | Route53, Cloudflare |
| SSH Bastions | AWS, GCP bastions |
This combination of cloud infrastructure and services supports WhatsApp’s core messaging platform.
WhatsApp’s Custom Server Software
While WhatsApp relies on standard server hardware and open source software like Linux, Erlang, FreeBSD for much of its backend, it also develops extensive custom server software to enable its unique features and scale. Some key examples include:
Custom Erlang OTP Applications
WhatsApp engineers have built many custom Erlang OTP applications that enable real-time messaging capabilities core to WhatsApp’s product. These perform functions like online/offline state management, push notifications, contact/group management and more.
Custom Extensions
To optimize performance for WhatsApp’s workloads, its engineers have developed various extensions and patches for open source tools like:
– WebRTC for multimedia messaging
– OpenSSH for secure management
– TLS for encryption
– FreeBSD for networking stack optimization
These custom extensions help WhatsApp efficiently scale its infrastructure.
Management & Monitoring Tools
WhatsApp has created internal platforms for managing and monitoring server clusters, pipelines, and application deployments. These provide insight into performance, reliability, and usage statistics.
AI/ML Services
WhatsApp employs extensive AI and ML trained on its messaging data to detect spam/abuse, match media, suggest responses and more. The custom models serve user-facing features.
Automation & Configuration Tools
WhatsApp has built advanced internal automation and configuration management tools for efficiently deploying and maintaining its massive server infrastructure.
The combination of open source software and custom code allows WhatsApp to achieve the performance, scale, and flexibility its platform requires.
WhatsApp’s Global Server Deployment
To provide low-latency connectivity worldwide, WhatsApp maintains server clusters in strategic, high-bandwidth data center regions across the globe. Some key locations include:
United States
WhatsApp operates servers extensively across the US including California, Virginia, Oregon, South Carolina and Texas. The US is WhatsApp’s largest infrastructure footprint.
Europe
Major European colocation centers like Frankfurt, Amsterdam, London, Madrid, Warsaw, Paris host WhatsApp servers to serve European users.
Asia
Significant WhatsApp deployment exists in Singapore, Mumbai, Seoul, Tokyo and Hong Kong for fast connectivity in densely populated Asian regions.
Brazil
Brazil is WhatsApp’s second largest market, and it maintains major infrastructure in São Paulo, Porto Alegre, Curitiba and other cities.
South Africa
WhatsApp has points of presence in Johannesburg, Cape Town and Durban to serve Africa’s second most populous country.
Middle East
Major Middle Eastern colocation hubs like Dubai and Abu Dhabi host WhatsApp servers to provide low latency connectivity across the Gulf region.
WhatsApp selectively deploys servers in lower density areas like Australia, China and Russia to maintain global coverage. Network peering and caching help further expand its footprint.
| Region | Major Server Locations |
|---|---|
| United States | California, Virginia, Oregon, Texas |
| Europe | Amsterdam, Frankfurt, London, Warsaw |
| Asia | Singapore, Mumbai, Seoul, Tokyo |
| South America | Sao Paulo, Porto Alegre, Curitiba |
| Middle East | Dubai, Abu Dhabi |
By deploying infrastructure close to users, WhatsApp minimizes latency for real-time messaging worldwide.
Server Counts
Exact server counts are not publicly disclosed by WhatsApp. However, experts estimate based on WhatsApp’s vast user base and data volumes that they likely operate:
– Tens of thousands of application servers
– Thousands of dedicated media servers
– Hundreds of petabytes of storage across database and storage clusters
– Thousands of memcached servers for caching
– Hundreds of load balancers
– Thousands of web servers
Their infrastructure likely spans hundreds of thousands of physical and virtual servers across their data centers worldwide. These massive server farms process over 100 billion messages per day.
As WhatsApp continues growing past 2 billion users, they need to keep scaling up their backend infrastructure proportionally to meet demand. Their next major milestone may be supporting over a trillion messages per day.
Network Infrastructure
In addition to its server infrastructure, WhatsApp’s global private network plays a critical role in keeping users connected. WhatsApp operates its own high-capacity WAN optimized for media messaging, with key technologies including:
Fiber Optic Cables
WhatsApp leverages intercontinental and intracontinental fiber cable systems for high-bandwidth, low-latency connectivity between its data centers worldwide. This includes major cables like MAREA, TAT-14 and numerous regional networks.
Points of Presence
WhatsApp maintains hundreds of points of presence globally inside top colocation data centers for proximity to users. This also enables peering with major ISPs.
Border Gateway Protocol
WhatsApp engineers use BGP to optimize routing between its data centers and leverage multiple transit providers for redundancy.
Software-Defined Networking
WhatsApp is transitioning towards a software-defined infrastructure that allows full programmatic control over routing and traffic management on its network.
Network Monitoring & Management
WhatsApp develops internal tools and platforms to monitor real-time network performance and quickly detect issues like outages, congestion and more.
WhatsApp’s well-engineered infrastructure plays a key role in keeping its service globally accessible and responsive. Their network capacity will need to grow as more countries come online and messaging volumes increase.
Security Infrastructure
Given the sensitive nature of user messaging data, security is a critical priority for WhatsApp’s infrastructure. Key measures include:
Encryption
WhatsApp deploys end-to-end encryption powered by the Signal protocol to secure messages in transit and at rest. Voice and video calls are also encrypted.
Hardened Data Centers
WhatsApp uses highly secure Tier IV data centers with strong perimeter protection and access controls. Facilities are geographically distributed to prevent single points of failure.
Web Application Firewalls
WAFs protect WhatsApp’s externally facing web endpoints from exploits like SQLi, XSS and common web application attacks. Rules and filters evolve dynamically.
DDoS Protection
WhatsApp leverages DDoS mitigation services to absorb and withstand large volumetric attacks intended to disrupt its service. This maintains uptime.
Penetration Testing
WhatsApp engages external security firms and bug bounty programs to ethically probe its infrastructure for vulnerabilities and improve defenses before malicious hackers can exploit flaws.
With so much sensitive user data, WhatsApp dedicates substantial resources to securing its systems against sophisticated cyberattacks. Maintaining user trust is imperative.
Major Technology Partners
WhatsApp relies on top cloud computing and technology vendors to power components of its infrastructure including:
Amazon Web Services
AWS provides on-demand cloud infrastructure like storage, data centers, web services and more to WhatsApp. AWS also hosts some of WhatsApp’s servers.
Google Cloud Platform
WhatsApp leverages Google’s cloud similarly to AWS for computing infrastructure, storage, networking and platform services.
Fastly
Fastly provides CDN services to WhatsApp for fast, secure delivery of media worldwide and absorption of traffic spikes.
Cloudflare
WhatsApp uses Cloudflare for managed DNS services, DDoS protection and speeding up content delivery around the globe.
Akamai
Akamai is another WhatsApp CDN partner for caching and serving high volumes of media traffic through localized edge servers.
By combining leading cloud providers, WhatsApp can flexibly scale its infrastructure without needing to build everything in-house.
Compliance Standards
As a global organization handling sensitive user data, WhatsApp conforms to various legal standards and compliance frameworks including:
GDPR
WhatsApp implemented strong data protection controls to comply with GDPR and give EU users more privacy rights and control over their information.
CCPA
For California users, WhatsApp adheres to CCPA regulations around data transparency, deletions and opt-outs.
ISO 27001
WhatsApp complies with ISO 27001 standards for information security management and best practices. Independent audits verify compliance.
SOC 2
WhatsApp undergoes SOC 2 audits to prove security, availability and confidentiality controls for user messaging data.
PCI DSS
For securing payment card data, WhatsApp complies with PCI DSS requirements around encryption, access controls and more.
Meeting global compliance standards demonstrates WhatsApp’s commitment to user privacy and responsible data practices.
Conclusion
WhatsApp operates an expansive, sophisticated technical infrastructure to provide seamless messaging capabilities to over 2 billion people worldwide. Key takeaways include:
– Thousands of geographically distributed servers optimize delivery
– A global private network connects data centers with low latency
– Leading technology vendors supply cloud infrastructure and services
– Security is a top priority from encryption to hardware hardening
– Billions of messages per day are processed across hundreds of thousands of servers
– Compliance with data regulations like GDPR and ISO standards
While most users only see the app on their smartphone, supporting ubiquitous messaging is incredibly complex behind the scenes. WhatsApp’s infrastructure team manages this complexity through engineering excellence and operational expertise. As technology and demand evolves, WhatsApp will continue innovating on infrastructure to connect people globally through immediate, secure communication.