In a Kongcast episode, Scott Lowe, a principal field engineer at Kong, discusses the functionality and benefits of a service mesh in modern application infrastructure. A service mesh is designed to handle communication between microservices within applications, providing features like authentication, traffic routing, and rate limiting, thus allowing developers to focus on business-specific features rather than connectivity concerns. Unlike API gateways, which manage north-south traffic (external to internal), a service mesh manages east-west traffic (internal service-to-service), offering a higher level of application awareness and functionality, such as mutual TLS for secure communication. This evolution of networking tools decouples logical networking from physical infrastructure, enhancing security and reliability without burdening developers with repetitive coding tasks. Although the industry has not yet developed an alternative to service mesh, variations exist in terms of supported technologies and platforms. The episode also features a demonstration of traffic permissions using the Kuma service mesh, highlighting its capability to enforce fine-grained access control beyond traditional methods.