Presentation about the academic project submitted as part of the "Distributed Systems" course at Politecnico di Milano (Academic Year 2007-08): a hierarchical, flat naming service implemented using CORBA-compliant services offered by J2SE.

1. Hierarchical Flat
Naming Service
Paolo Somaglia Rocco Giovanni Versaci
(708683) (708259)
Academic year 2007-2008

2. Assignment description
• Implement a hierarchical naming service (for
flat names).
– The system needs to support:
• Insertion
• Deletion of any resource given its name
• Search
• Insertion of new processes (name servers) in the hierarchy
– Assumptions:
• Reliable processes
• Reliable channels
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3. Introductory Overview
• Chosen middleware:
• Chosen implementation: J2SE ORB
– Why not JacORB?
• Recurrent errors, especially on Windows
• Most of the offered services wasn’t needed for our problem
• After some research, we decided to draw
inspiration from the name service described in:
– Gerco Ballintijn, Locating Objects in a Wide-Area
System, Ph.D. thesis, Vrije Universiteit Amsterdam,
2003
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4. How the solution works
• The administrator can add nodes to the name
server hierarchy, which is stored in the Name
Service embedded in the ORB.
• Each client can:
– Register a resource (i.e. its proxy) under any name;
– Unregister a resource given its name;
– Search a resource by name (as in the DNS);
– Search for all the resources having the same name.
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5. Class diagram
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6. Deployment view
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7. Node insertion
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8. Node hierarchy visualization
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9. Choice of the node to be queried
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10. Registration of a resource by its name
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11. Search for a resource by its name
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12. Search for all resources with name N
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13. The end
Thanks for watching!
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