Advantages.

Easy implementation

If we want to diagnose a problem directly check the specific layer.

Performance increase.

Instead of divide into module divide into layers.

Reliability bcz of visiting whole layer for specific task.

Disadvantages.

If you want to diagnose the CPU, have to check kernel.

Layer working divide into layer is difficult task.

No layer can call services except its own.

Implementation of Layers working is tough.

No services can invoke from another layer.