Servers
Important elements:
-  Hardware
	
	-  Internal expansion space 
-  Upgrade path 
-  Input and output 
-  Rack mounting 
-  Exclusive front access 
-  Hot swapping 
-  RAID storage 
 
-  Maintenance policy 
-  Active backup plan 
-  Installation at the computer centre 
-  Specialised software 
-  Remote access 
-  Separation of operational network from the administration network 

Rack-mounted servers