Network Topologies

| Concept | Definition | Used For | Pros | Cons | | --------------------------- | -------------------------------------- | ---------------------- | -------------------------- | ----------------------- | | Mesh | Every node connected to every other | WAN, data centers | Redundant | Expensive | | Hybrid | Mix of multiple topologies | Large networks | Flexible | Complex | | Star / Hub-and-Spoke | Central device connects all others | LAN | Simple | Central failure | | Spine-Leaf | All leafs connect to all spines. Spine switches and the core layer and interconnect all leaf switches. Leaf switches connect servers and devices. | Data centers | Scalable, low latency | Cost | | Point-to-Point | Single dedicated link | WAN or VPN | Simple | Not scalable | | Three-Tier | Core(Fast backbone, high-speed switching), Distribution(Policy enforcement, routing between VLANs), Access(Connects end devices (PCs, printers)) | Enterprise networks | Organized | Costly | | Collapsed Core | Core + Distribution merged | Small networks | Cheap | Less redundancy | | North–South Traffic | In/out of data center | Client-server | Controls external flow | Can be bottleneck | | East–West Traffic | Within data center | Server-server | Efficient internal flow | Needs fast switching |