| L4 (14)  
  
  
  L3-L4 Microkernel Family   - Lean, with fast, message-based, synchronous IPC, simply-used external paging mechanisms, security mechanism based on secure domains: tasks, clans, chiefs. Kernels try to implement only a minimal set of abstractions on which OSs can be built flexibly. L3 h - http://os.inf.tu-dresden.de/L4/        
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