Hierarchical FlatNaming Service

Rocco Giovanni Versaci

(708259)

Paolo Somaglia

(708683)

Academic year 2007-2008

Academic year 2007-2008Paolo Somaglia and Rocco Giovanni Versaci 1

Assignment description

• Implement a hierarchical naming service (for

flat names).

– The system needs to support:

• Insertion

• Deletion

• Search

• Insertion of new processes (name servers) in the hierarchy

– Assumptions:

• Reliable processes

• Reliable channels

of any resource given its name

Academic year 2007-2008Paolo Somaglia and Rocco Giovanni Versaci 2

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

Academic year 2007-2008Paolo Somaglia and Rocco Giovanni Versaci 3

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.

Academic year 2007-2008Paolo Somaglia and Rocco Giovanni Versaci 4

Class diagram

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Deployment view

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Node insertion

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Node hierarchy visualization

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Choice of the node to be queried

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Registration of a resource by its name

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Search for a resource by its name

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Search for all resources with name N

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The end

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