The Spine-and-Leaf architecture is the preferred pod-based deployment model in modern data centers because of its high scalability and flexibility. In this topology:
Leaf switches connect to servers and act as the access layer.
Spine switches function as the core layer, interconnecting all leaf switches.
This non-blocking, highly redundant model supports predictable latency, easy horizontal scaling, and load balancing, making it ideal for cloud-scale and virtualized environments.
Top of Rack (ToR) and End of Row (EoR) are physical cabling layouts that do not inherently provide the same level of architectural scalability.
Fabric Extender models extend switch ports but depend on upstream switches for intelligence, limiting flexibility.