What does the term "north-south traffic" refer to in network architecture?

The term "north-south traffic" refers to the flow of data between external users and internal resources, such as those in the cloud. This type of traffic typically represents communication that occurs between the users accessing services over the internet and the resources those services are deployed on, such as applications or databases hosted in the cloud.

Understanding the concept of north-south traffic is crucial in network architecture because it helps in designing and managing the security and performance of connections that drive interactions between external clients and the core business services hosted in data centers or cloud environments. This distinction is particularly important for optimally configuring firewalls, load balancers, and other security measures aimed at protecting these communication pathways.

In contrast, traffic between VMs in a data center, between internal servers, or traffic within the same LAN segment are categorized differently, often referred to as "east-west traffic." This distinction highlights the differences in routing, performance analysis, and security considerations that need to be taken into account for different types of network traffic.