star

Each workstation has its own direct line to the server. Connections to the server are made with hubs or switches.

Hubs connect many lines together.

Switches allow the network manager to connect certain workstations to specific servers.

Advantages:
Reliable - if one connection fails, it does not affect others.
Good performance, fewer data collisions as each workstation has its own line.
Good Security - no workstation can interact with another without going through the server first.

Disadvantages:
Expensive to install - lots of cables required.
Installation is an expert job.
Extra hardware required such as hubs, switches and wiring centres.

Star networks are normally preferred because of their reliability.