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|  Messaging Layer | 
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    Inherits lessons from previous systems:
    
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	X11, XNS Courier, ONC RPC, CORBA IIOP, DCOM, Java RMI, DCE RPC, TCP/IP
    
 
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    Contains a lightweight but powerful type system
    
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	Support for optional and mandatory extensions
      
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	Support for incremental deployment of independently-developed extensions
      
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	Can serve as substrate for Java RMI, CORBA, DCOM
    
 
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    Highly optimized wire protocol
    
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	Byte-efficient and low parsing overhead (XDR based)
      
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	Pipelining and batching
      
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	Caching of method and resource identifiers