Suggest an editImprove this articleRefine the answer for “What types of topologies exist?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)Network topologies can be divided into **classic (basic)** ones and **modern** ones (used in large networks and data centers). **Key point:** in practice, star and tree structures are used most often, while data centers use modern topologies such as Spine-Leaf or Clos.Shown above the full answer for quick recall.Answer (EN)ImageNetwork topologies can be divided into **classic (basic)** ones and **modern ones (used in large networks and data centers)**. Below are all the main types that are important to know for an interview. --- ## Classic topologies ### 1. "Bus" topology All devices are connected to a single shared cable. **Pros:** - simple and cheap - minimal cable usage **Cons:** - cable damage breaks the whole network - many collisions - almost never used today **Where it was used:** old versions of Ethernet (10BASE2/5). --- ### 2. "Star" topology - the main topology of modern Ethernet All nodes are connected to a central device - a **switch (less often a hub)**. **Pros:** - a failure of one node does not affect the network - easy to scale - high performance **Cons:** - a failure of the central device → the network becomes unavailable **Where it is used:** practically all home and office LANs. --- ### 3. "Ring" topology Devices are connected in a chain forming a ring. **Pros:** - no collisions (Token Ring, FDDI) **Cons:** - a break in the ring causes problems - difficult to upgrade **Where it was used:** in old corporate networks. --- ### 4. "Fully connected" / "Mesh" topology Each node is connected to several others. Can be: - **full mesh** - every node with every other - **partial mesh** - only important nodes have many connections **Pros:** - maximum fault tolerance - high bandwidth **Cons:** - expensive - hard to manage and scale **Where it is used:** Wi-Fi Mesh systems, provider backbones. --- ### 5. "Tree" topology A hierarchy of devices: root switch → distribution switches → access switches. **Pros:** - clear structure - convenient for scaling **Cons:** - dependency on top-level equipment **Where it is used:** the classic structure of corporate LANs. --- ## Combined topologies In practice, real networks almost always use **mixed topologies**, for example: #### Star-bus several stars joined by a shared bus (looked like stars connected by hubs in the 90s). #### Star-ring switching equipment forms a ring, while end stations form a star. #### Hybrid Mesh/Tree modern networks of telecom operators. --- ## Modern data center topologies (if you want to stand out in an interview) ### 1. Clos topology A hierarchical, multi-level mesh structure with equal paths between nodes. ### 2. Fat-Tree A variant of the tree, but with increased bandwidth at the upper levels. ### 3. Spine-Leaf A two-level topology: - **Leaf** - switches that servers connect to - **Spine** - core switches **Every Leaf is connected to every Spine**. This is the standard in modern data centers. --- ## How to answer correctly in an interview > **There are several types of topologies: bus, star, ring, tree, and mesh.** > **In practice, star and tree structures are used most often, while data centers use modern topologies such as Spine-Leaf or Clos.** --- ## Cheat sheet (5 seconds before the interview) - **Bus** - a shared cable (outdated). - **Star** - the most common option. - **Ring** - rare, historical. - **Tree** - corporate LANs. - **Mesh** - high fault tolerance, DC and Wi-Fi mesh. - **Spine-Leaf / Clos** - modern data centers.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.