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Database Agents 1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber [email protected] +43 7236 3343 893 www.scch.at
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Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber [email protected] +43 7236 3343.

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Page 1: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 1

Mobile Agents In An Insecure Environment

Tutorial

IIWAS 2002, Bandung, 10 – 12 Sept 2002

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 2: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 2

Who am I?

Project Manager Evaluation of Mobile

Agent Platforms

Topics of research Mobile and distributed

systems

Wireless communictation technolgies

Page 3: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 3

Virtual Tutorial CD

http://www.scch.at/agents

All slides as PDF file

Source Code

Java Class Files

Grasshoppernot included due torestrictions - However, Grasshopper can be downloaded (evaluation and non-commercial licenses free) at http://www.grasshopper.de

Page 4: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 4

Overview

Introduction to agent technology Definition

Classification

Standardization

Agent capabilites Mobility

Communication and Cooperation

Security

Page 5: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 5

General Remarks

Prerequisites

None

Mobile Agents for Databases Using Grasshopper by Ludwig Klug

Conceptual 2nd part of this tutorial

Practical application of mobile agents in a database framework with demos

Page 6: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 6

Introduction

to Agent Technology

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 7: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 7

Agent-Based Computing Hype or Paradigm Shift?

“My guess is that agent-based computing will be what object-oriented programming was in the 1980s. Everybody will be in favor of it. Every manufacturer will promote his product as supporting it. Every manager will pay lip service to it. Every programmer will practice it (differently). And no one will know just what it is.” (Jennings, OOPSLA 2000)

Page 8: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 8

Strong Increase in Research Activities

1st Int. Workshop on Agent Systems and Applications (WOA2000)

1st Int. Workshop on Web Agent Systems and Applications (WASA 2000)

2nd European Agent Systems Summer School (EASS 2000)

2nd Int. Symposium on Mobile Agent Applications (MAA'2000)

2nd Int. Symposium on Agent Systems and Applications (ASA 2000)

4th Int. Symposium on Mobile Agents (MA 2000)

Page 9: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 9

Strong Increase in Research Activities

4th Int. Conference on Autonomous Agents (Agents 2000)

4th Int. Conference on Multi Agent Systems (ICMAS 2000)

4th Int. Workshop on Cooperative Information Agents (CIA 2000)

5th Int. Conference on Autonomous Agents (Agents 2000)

6th ECOOP Workshop on Mobile Object Systems (ECOOP 2000)

6th Int. Conf. on Information Systems, Analysis and Synthesis (ISAS 2000)

Agent-Oriented Information Systems (CAiSE 2000)

Page 10: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 10

Increased Availability of Systems

AgentBuilder

AgenTalk

Agentx

Aglets

Concordia

DirectIA

Gossip

Grasshopper

iGEN

Intelligent Agent Factory

JACK Intelligent Agents

JAM

Jumping Beans

LiveAgent

Page 11: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 11

Increased Availability of Systems

MadKit

Microsoft Agent

NetStepper

Pathwalker

Swarm

UMPRS

Via

Voyager

Agent Factory

D‘Agents

Agent Tcl

TACOMA

Ascape

Bee-gent

Page 12: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 12

Increased Availability of Systems

Mobiware

SOMA

MOLE

RETSINA

Zeus

Ara

EXCALIBUR

Gypsy

Hive

Inforsiders

JADE

JAT

Page 13: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 13

State of the Art: Overview

Definition and Classification Definition

Classification

Agent Types

Standardization

Basic Characteristics

Page 14: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 14

Definition

What is an agent?

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 15: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 15

Definition

No unique definition in literature Various classification schemes

Various characterizing features (mobility,...)

Page 16: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 16

Definition

Provisional Definition (Software Agents)

“Software program that can do some defined action for a user, which has some kind of intelligence to give the ability to do part of its function autonomously and which can interact with its environment.“

Page 17: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 17

Classification (I)

Classification by mobility

Mobile or not mobile?

Interaction capabilities

Deliberative or reactive?

Ideal attributes

Learning – autonomy – cooperation

Area of influence

Autonomy – intelligence - mobility

Page 18: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 18

Classification (II)

Learning – Autonomy – Cooperation

SmartAgents

CollaborativeLearningAgents

CooperationAutonomy

InterfaceAgents

CollaborativeAgents

Learning

Page 19: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 19

Classification (III)

Area of Influence

Characteristic

Decision Theory

Mobility

CommunicationNetwork

Autonomy

Psychology

Reactivity

Proactivity

LearningCapability

Character

Distributed artificialIntelligence

Cooperation

Communication

ArtificialIntelligence

Page 20: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 20

Classification (IV)

Autonomy – Intelligence - Mobility

Mobility

autonomy

intelligence

Mobile Objects

Mobile Scripting

static preferences

consequences

planning

learning

Asynchronity

User presentation

Interaction with data

Interaction with application

Interaction with services

Expert Systems

Age

nts

with

fixe

dfu

nctio

nalit

y

Page 21: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 21

Agent Types

Reactive Agents

Hybrid Agents

Heterogeneous Agents

Smart Agents

Collaborative Agents

Interface Agents

Mobile Agents

Information/Internet Agents

Page 22: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 22

Standardization

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 23: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 23

Overview

FIPA Foundation of Intelligent Physical Agents

Covers the whole range of agent software architecture

MASIF Mobile Agent System Interoperability Facility

Covers only mobile agents

Convergences and differences

Page 24: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 24

FIPA

Software Agent

Agent Platform Agent

Management System

Directory Facilitator

Agent

Communication Channel

Internal Platform Message Transport

Agent

Communication Channel

Page 25: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 25

MASIFRegion

Communication Channel (ORB)

Agent System (Agency)

Place

Agents

Agency Services

MAFAgent

System

RegionRegistrationComponent

MAFFinder

register agent/place/systemde-register agent/place/systemlookup agent/place/system

create/suspend/resume/terminate agentreceive agentlist agents/placesget MAFFinderget agent system typeget agent status,...

Page 26: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 26

Convergences & Differences

Convergence

Differences

FIPA: whole platform

MASIF: minimal definitions

Communication Channel (ORB)

Agent Platform

AgentManagement

Service

DirectoryFacilitator

AgentCommunciation

Channel

Internal Platform Message Transport

MASIF-access

part

FIPAagent

platform

Page 27: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 27

State of the Art: Overview

Definition and Classification

Basic Characteristics Mobility

Communication and cooperation

Security and authentication

Information filtering and retrieval

Learning and planning

User modeling

Open issues

Page 28: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 28

Characteristic Properties

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 29: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 29

Mobility of agents

Ability of agents to move between computers

Agents: „move“ –> „migrate“

Weak migration

Strong migration

Strong (data and control)

Weak (data only)

Page 30: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 30

Mobility of agents

Basic platform runtime required on each computer

Distribution of task when needed

Database queries within DBMS

Searching within network

Weak (data only)

Page 31: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 31

Orders

WirelessNetwork

HQ

WiredNetwork

NewsSpecsBGW

Orders

WirelessNetwork

HQHQ

WiredNetwork

NewsSpecsBGW

Communication

Communication Protocols, Procedures

Agent communication languages

– Knowledge Query and ManipulationLanguage (KQML)

– FIPA-ACL

– XML

Page 32: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 32

KQML Message

(tell :sender sellerAgent

:receiver fhBot

:in-reply-to id333-222-289

:ontology ecbk12

:language Prolog

:content “price(ISBN453276,20.98)”

)

Page 33: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 33

Cooperation

Task Processor

Local database

Contract processoror

Communication Processor Network

Contract-Net-Node Protocol

Page 34: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 34

TNT

TNT

TNT

TNTTNT

TNTTNT

TNT

TNT

TNT

TNTTNTTNTTNT

TNTTNT

Security and Authentication

Threats Unauthorized disclosure of information

(Confidentiality)

Denial of service (DoS) - availability

Corruption of information(integrity)

Page 35: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 35

TNT

TNT

TNT

TNTTNT

TNTTNT

TNT

TNT

TNT

TNTTNTTNTTNT

TNTTNT

Security and Authentication

Malicious Strategies Agent attacking platform

Agent attacking agent

Platform attacking agent

Agent system attacking

Mechanisms Encryption, SSL, PKI, Code Signing,

Trusted Third Parties

Page 36: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 36

Information Filtering and Retrieval

Basics Unstructured information

Different kinds and sources of information

Text representation Free text search

Semantic approach

Information Filtering Long-term information retrieval

Page 37: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 37

Information Filtering and Retrieval

is based on supplies

with with

stored in on

Information retrieval

Analysis of data

Principles of knowledge representation

Information during the retrieval

Transformations

Internal knowledge structure (database

structures)

analysis of data units

indexing classifying retrieval operations

documents

Page 38: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 38

Learning and Planning

Planning

Plan coordination

Single - Agent - Planning

Task-oriented Planning

distributed Multi-Agent-Planning

Multi-Agent-Planning

Central Multi-Agent-Planning

Page 39: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 39

Learning and Planning

Page 40: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 40

User Modeling

Simulation of user‘s preferences Required for information filtering and

retrieval

Creation of user profile Initial profile

Observing user patterns and preferences

=> Customized information search

user

User profile Agent

Information source

Page 41: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 41

Fundamental Questions, However, Remain

What is the essence of agent-based computing?

Why are agents an appealing computational model?

What are the drawbacks of an agent-oriented approach?

What are the implications for future software architectures?

Page 42: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 42

Ongoing Research

Learning and planning capabilities Distributed planning

Distributed knowledge collection and representation

User modeling User preferences for information retrieval

and filtering

Page 43: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 43

Ongoing Research

Communication and cooperation Agent communication

Agent negotiations

Security Encryption of data

Digital certificates

Page 44: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 44

Commercial Agent Platforms

Selection

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 45: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 45

Aglets

http://www.aglets.org WWW

many security features available

easy to use GUI for administration of the agent platform

book available; open source

Characteristics:

1.1.xJDK Version:

1.1Current Version:

Open source (formerly IBM)Manufacturer:

Page 46: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 46

Grasshopper

http://www.grasshopper.de WWW

support for the current standard security concepts

useful GUI for administration and monitoring of agents

detailed documentation

Characteristics:

1.2.2JDK Version:

2.2Current Version:

IKV++ GmbH, Berlin, GermanyManufacturer:

Page 47: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 47

Jumping Beans

http://www.jumpingbeans.com WWW

security features are on a high level of maturity

documentation not up-to-date

migration of the agents is very slow

thread problem using a GUI

Characteristics:

1.2JDK Version:

2.2Current Version:

Ad Astra EngineeringManufacturer:

Page 48: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 48

Soma

http://www-lia.deis.unibo.it WWW

main aspect in security and mobilityusing open standards like MASIF or FIPAno useful documentation available

Characteristics:

1.2JDK Version:

4.0Current Version:

Laboratory of Advanced Research on CS, University of Bologna, Italy

Manufacturer:

Page 49: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 49

Using Agents

For Real-World Applications

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at

Page 50: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 50

Why Mobile Agents?

Real Deployment

Reduce Network Load

Overcome Network Latency

Synchronity and Asynchronity

Dataset

Dataset

Dataset

Dynamically selected

proxy site

Merged and filtered data

streamDataset

Dataset

Dataset

Dynamically selected

proxy site

Merged and filtered data

stream

Server

Dataset

Text documents,numerical data, etc.

Client/Proxy

Client/Proxy

Dataset

Server

DatasetDataset

Text documents,numerical data, etc.

Client/Proxy

Client/Proxy

Dataset

Page 51: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 51

No Agents, Please!

Relative to Mobile Agents, Client/Server is Network Bound

Use mobile agents if your application does a little processing on a large dataset

Relative to Client/Server, Agents are CPU Bound

Do not use mobile agents if your application does a lot of processing on a small dataset

Page 52: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 52

Next Generation Systems

Remote communication just as fast as RPC

No penalty for stationary agent

Just-in-time compilation and software fault isolation

Execution at near-native speeds

Code caching

Low migration overhead

=> “Mobile agents will do no worse than traditional implementations, and will often do better“.

[Bob Gray, Dartmouth College, ASA/MA ‚2000]

Page 53: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 53

What is the essence of agent-based computing?

Component-based software engineering of the future.

Small pieces of code (fewer errors).

Easy “updates” because updates are not necessary.

Page 54: Database Agents1 Mobile Agents In An Insecure Environment Tutorial IIWAS 2002, Bandung, 10 – 12 Sept 2002 Franz Gruber Franz.gruber@scch.at +43 7236 3343.

Database Agents 54

Questions – Discussion

What do you think??

Franz Gruber

[email protected]

+43 7236 3343 893

www.scch.at