FIPA-OS

This talk introduces the basic architecture for FIPA-OS. It summarizes the material from:

P. Buckle and R. Hadingham. FIPA-OS: FIPA Everywhere. [1] 1999. Presentation.
FIPA-OS Developer's Guide. [2]
FIPA-OS Tutorials. [3]
The FIPA-OS homepage [4].
The FIPA-OS Javadocs [5].

FIPA-OS is an open source implementation of the FIPA standards.
It is currently being developed mostly by Emorphia corporation. It was originally developed by Nortel networks.
Written in Java 2.
There is also a MicroFIPA-OS version available that runs on the iPaq.
You will need to install it yourself, so get going.

fipaos.agent
The agent package is used exclusively for any mandatory components of an agent. For example, the Conversation Factory, State Manager etc. Classes that form a large component should be grouped into a sub-package as seems most logical and appropriate (e.g. The State Manager is placed in fipaos.agent.state). Classes in this package are required to run the platform.
fipaos.comm
This package is for the communications and transport classes of the platform. Classes exclusively of this type should be put into this package as appropriate (see existing package structure for guidance). Developers not working on comms layer classes should not need to use this package. Classes in this package are required to run the platform.
fipaos.fipa
The fipa package is for FIPA specific classes. Any classes that define or handle FIPA specific data or objects should be placed in this package. Classes in this package are required to run the platform.
fipaos.ont
The ont package is for ontology specific classes. If a class belongs to an ontology component then it should be placed in a sub-package named after the ontology that it applies to. For example, the fipa-agent-management ontology classes are in fipaos.ont.fipaman. Classes in these sub-packages are required to run any components of the platform that use the specific ontology in the sub-package. Classes in the ont package (but not in a sub-package) and the ont.fipaman package are required to run the platform.
fipaos.parser
The parser package is for classes that form language specific parsers. Parser components should be in sub-packages named by the language that they apply to. Classes in this package are required to run the platform.
fipaos.platform
The platform package is for platform specific classes that are not agent components. This includes platform agent classes. Classes in this package are required to run the platform.
fipaos.skill
The skill package is used for optional agent components that can be plugged-into the agent to provide it with a specific skill. For example, database access is a sub-package of the skill package. Classes in this package are not required to run the platform in general, although any platform agents that use specific skills will introduce a requirement for those specific skill classes.
fipaos.tool
The tools package is for platform and agent level tools that are not required for the use of the platform. This includes such tools as testing harnesses, information tools etc.
fipaos.util
The util package is used for agent classes that are not mandatory for use in an agent, but are provided as helper classes that are not application specific, and are not part of a skill component. Classes in the util package are required for correct operation of the platform. Examples of util classes are UTC time handlers and diagnostics output handlers.

An Envelope wraps an ACL message. Its constructor takes as a parameter the ACL message.
A Message is a wrapper for the Envelope and the ACL object.
The DIAGNOSTICS class provides the API for printing debugging messages to screen and file.

The FIPAOSAgent is the class you will extend when implementing an agent.
Upon initialization it creates:
1. A Message Transport Service (MTS)
2. A Task Manager
3. A Conversation Manager
It provides many useful member functions (see below).

The TaskManager class stores task objects with their associated conversation IDs for an agent.
Tasks are self-contained (reusable) pieces of code that carry out some task and (optionally) return a result, can send or receive messages, and have little dependance on the agent they are executed in.
The agent must add it's tasks during initialisation.
Each task can be used to handle the messages for a particular conversation that an agent participates in. The agent can be executing many tasks.
- For example. if an agent registers with a DF on startup, one task object can be used to handle this conversation without having to store any state for other conversations - even if they have the same protocol.
Tasks can spawn child tasks.
You extend the Task class for each task you want. The important methods are:
- newTask: Initialises the given task.
- startTask: is invoked mmediately after the task has been initialised by newTask().
- done: When invoked, parent task will have the appropriate doneX() method invoked.
- forward: Sends a Message.
- handleX: as in handleInform. These methods must be overriden by your class.
- newTask: Initialises the given task, and invokes its start method

Provides the ability to track conversation state at the performative level.
Can make sure a protocol (IP) is followed. The protocol is passed as a String using a special encoding language.

The Ping Agent will try to ping all the other ping agents that it knows about every 5 minutes, and will respond to any pings it receives. It does this with tasks:

IdleTask: Is started first. Gets all other agents from DF. After 5mins it starts pinging (PingALLTask). It also responds to any pings it receives (PingResponseTask).
PingAllTask: Sends a ping to all agents (PingTask).
PingTask: Sends a ping.
PingResponseTask: Replies to pings.

FIPA-OS

1 Introduction

2 Architecture

3 Packages

4 Core Class: ACL

5 Core Class: Envelope, Message, Diagnostics

6 FIPAOSAgent

7 TaskManager

8 ConversationManager

9 GenericAgent

10 Ping Agent Example

11 PingAgent

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