Cloud networking core encompasses the fundamental building blocks of virtual network infrastructure in modern cloud platforms. VPC (Virtual Private Cloud) architecture serves as the isolated network foundation, enabling organizations to design secure, scalable, and highly available network topologies within cloud environments. Understanding CIDR planning, route propagation, and multi-tier segmentation is critical to building production-ready systems that balance security requirements with connectivity needs. Cloud networking differs from traditional on-premises networking in its software-defined nature — gateways, routes, and security policies are configured as code rather than physical hardware, allowing unprecedented flexibility but requiring mastery of new abstractions and gotchas that can silently degrade performance or expose security gaps.