East-west traffic in a cloud environment refers to the lateral communications that occur between servers, containers, or applications within the same data center or cloud network, without involving the core network or external endpoints.
East-west traffic is a key concept in modern data center and cloud network architectures, where workloads are often distributed across multiple servers or containers. This term contrasts with north-south traffic, which represents the traffic that enters and exits the data center to the wider internet or other external networks.
In detail, east-west traffic includes:
- Data replication and synchronization between servers
- Internal load balancing
- Database sharding operations
- API calls between microservices
- Internal system monitoring and management traffic
With the rise of microservices and containerization, east-west traffic has increased substantially as applications are decomposed into smaller, more granular components that frequently communicate with each other. This growth in lateral traffic patterns necessitates efficient network designs that can handle high volumes of internal traffic without bottlenecks. Software-Defined Networking (SDN) and Network Functions Virtualization (NFV) are commonly used technologies that help optimize east-west traffic flow.
Some common misconceptions include conflating east-west traffic with external network communication or underestimating its impact on network design. In reality, the efficient handling of east-west traffic is crucial for application performance, particularly in distributed systems like those found in cloud computing and large-scale virtualized environments.