Because of the high quality of the papers written by the seminar participants, the seminar supervisors decided to officially publish the results as working paper of the Technische Universität München. You can find the link to the publication in the links-section at the end of this article.

Please feel free to share your thoughts on this paper.

Cost/Benefit-Aspects of Software Quality Assurance – Abstract:

Along with the ever more apparent importance and critically of software systems for modern societies, arises the urgent need to deal efficiently with the quality assurance of these systems. Even though the necessity of investments into software quality should not be underestimated, it seems economically unwise to invest seemingly random amounts of money into quality assurance. The precise prediction of the costs and benefits of various software quality assurance techniques within a particular project allows for economically sound decision-making.

This paper presents the cost estimation models COCOMO, its successor COCOMO II and COUALMO, which is a quality estimation model and has been derived from COCOMO II. Furthermore an analytical idealized model of defect detection techniques is presented. It provides a range of metrics: the return on investment rate (ROI) of software quality assurance for example. The method of ROI calculation is exemplified in this paper.

In conclusion an overview on the debate concerning quality and cost ascertaining in general will be given. Although today there are a number of techniques to verify the cost-effectiveness of quality assurance, the results are thus far often unsatisfactory. Since all known models make heavy use of empirically gained data, it is very important to question their results judiciously and avoid misreadings.

Download:

Cost/Benefit-Aspects of Software Quality Assurance

Presentation

Links:

• Master Seminar Software Quality – Official Website
• Selected Topics in Software Quality – Working Paper
  Technical Report TUM-I0824, Institut für Informatik, Technische Universität München, July 2008.

In the last couple of weeks I have been working a lot with different databases which I had to connect to from Java. It is sometime stressful to look up the right format of the connection string to the database. Even though, these strings should, or are meant to be standardized, they are not.

I found this very helpful website ConnectionStrings.com which lists the connection strings for open-source as well as professional commercial databases. This list includes among others, the connection strings for Microsoft SQL Server 2008, MySQL, Oracle, IBM DB2, Informix, Postgre SQL, Caché, SQLite, …

I want to share this information with you, because it can save you a lot of time, looking up those strings in tutorials or in the documentation of the different databases.

Links:

• ConnectionStrings.com

Was ist VPN und Wieso braucht man das?

Virtual Private Network (dt. virtuelles privates Netz; kurz VPN) ist ein reines Softwareprodukt (daher „virtuell“) und dient der Einbindung von entfernten Geräten eines benachbarten Netzes an das eigene (private) Netz, ohne dass die Netzwerke zueinander kompatibel sein müssen. (Wikipedia)

Oder noch vereinfachter ausgedrückt, sie können VPN verwenden um sich gesichert in ein Netzwerk einzuwählen. Ich für meinen Teil gebrauche VPN um mich an der Uni übers WLAN mit dem Internet zu verbinden. Um den Missbrauch von öffentlichen WLANs zu vermeiden, setzten nämlich viele Universitäten eine zusätzliche VPN Authentifizierung ein bevor man ins Internet gelangen kann.

Anleitung: Installation und Konfiguration der VPN Software für das Nokia E51

Zuerst werden sie mit Entsetzen feststellen, dass obwohl Nokia das E51 als VPN-fähiges Handy verkauft, leider kein VPN Client installiert ist, und es eigentlich keinen gibt. Allerdings kann man für das E51 den VPN Client des Nokia N80 verwenden. Diesen VPN-Client für das Nokia N80 gibt es allerdings nicht mehr offiziell von Nokia zu downloaden.

Ich kann an dieser Stelle den Client nicht online stellen, aber wer bei Google nach nokian80vp184809.sis oder Nokia_N80_VPN_client.sis sucht dürfte fündig werden. Dieser Client ist allerdings auch schon nicht mehr gültig (die Signatur ist abgelaufen). Der Client kann allerdings trotzdem installiert werden indem man die Uhrzeit des Handys für die Zeit der Installation zurückstellt (siehe Screenshots).

Das zweite was man braucht ist eine vpn_policy.sis. Wie man eine solche für sein VPN-Netz erstellt und signiert wird an dieser Stelle nicht erklärt. Ich verweise aber an dieser Stelle auf die exzellente Beschreibung “nokia vpn client howto” von pipip.de. Falls Sie das VPN des Münchener Leibniz Rechenzentrum der Bayrischen Akademie der Wissenschaften verwenden wollen (z.B als Student der LMU oder der TU München) können Sie sich auf dieser Seite die benötigte vpn_policy.sys downloaden. Diese Policy müssen sie dann nur wie auf der Seite vom LRZ beschrieben von http://www.symbiansigned.com/ für Ihr Handy signieren lassen.

Wenn Sie nun den Nokia N80 VPN-Client haben und auch die vpn_policy.sys erfolgreich erstellt ist die meiste Arbeit eigentlich schon getan und sie können nun beide Anwendungen mit der Nokia PC Suite auf Ihr Handy übertragen. Die weiteren Schritte zur Installation der Software auf dem Handy sind als Kommentare unter den jeweiligen Screenshots verfasst.

Screenshots der Installation des VPN Clients und der VPN Policy auf dem Nokia E51

Kommentare, Kritik, Anregungen

Falls sie Kommentare, Kritik oder Anregungen zu diesem Artikel haben, verwenden sie die Kommentarfunktion des Artikels um mir jene mitzuteilen. Somit kann nicht nur ich, sondern jeder diese lesen und etwas nützliches daraus ziehen.

Linkliste

1. Nokia vpn client howto von pipip.de
2. Wo gibt es Nokia Mobile VPN Software? (für E51)
3. VPN mit Symbian S60 Smartphones beim LRZ
4. Google Query nach nokian80vp184809.sis und Nokia_N80_VPN_client.sis könnte hilfreich sein.
5. Nokia PC Suite
6. Nokia E51 bei nokia.de

Abstact

Software systems are becoming more and more omnipresent and pervasive in our daily environment. A life without software systems is not imaginable any-more. As a matter of fact it is important that software systems meet today’s high quality requirements. To achieve those, it is of paramount importance that the evolution of existing systems as well as the construction of new systems is carried out very carefully. To deliver good software, it is a prerequisite that development teams precisely know how systems behave at runtime, thereby enabling them to check compliance between the intended and the actual system behaviour.

This thesis contributes to the comparison process between the runtime behaviour and the static architecture of a software system. In the conceptual part of this work, the different elements of a software system are partitioned into categories. Furthermore, algorithms to perform this classification are introduced. These are applied to a set of runtime traces and the resulting classification of components and relations is used to determine the architectural coverage of the traces. The architectural coverage is a metric that measures the degree to which elements in recorded runtime behaviour (e.g. in a trace) capture elements of the static structure of the software system´s architecture. Because these traces are generally created by running dynamic test cases, it is possible to indirectly make a statement on the quality of the test cases.

In the practical part of this work, the technical feasibility of the theoretical concepts is proven in form of a prototype application. This prototype is realized as an extension to the Software Architecture Visualization and Evaluation tool (SAVE), an application developed by the Fraunhofer Institute for Experimental Software Engineering in Kaiserslautern.

The prototype supports importing, visualizing and evaluating dynamic runtime data and can detect common, unique and variable components among a set of runtime traces. Based on this information, the tool computes the degree of coverage for each type of components. Furthermore, the tool enables the abstraction and visualization of traces, thus offering an approach to support architecture reconstruction.

Presentation – Colloquium

Download
Evaluating the Architectural Coverage of Runtime Traces – Thesis
Evaluating the Architectural Coverage of Runtime Traces – Presentation

SMSing is a simple client/server based application to send SMS text messages through the Internet using Clickatell as service provider. The application supports multiple users, credits, logging aso. In the current version, SMSing should not be used in a productive environment, but shall demonstrate how to use and combine different technologies to send SMS´s. Nevertheless SMSing is really interesting for people sending lots of SMS who are bored to type the text using the keyboard of their mobile phones and pay the high prices of their mobile providers. SMSing even allows you to send anonymous messages, or messages with fake sender-number.

On the server side the application uses PHP for the scripting and mySQL for the storage of the user logins, credits, logging aso. If you configure a callback URL in your Clickatell Central API account, you even get the delivery status and time of your messages.

On the client side a simple Java 5.0 GUI forwards the messages to the server application, and the server application does the logging and billing and forwards the message to the Clickatell servers.

For further information you should consult the Readme file. The software is perfectly compatible with any PHP hosting provider.

Download
SMSing – Binaries
SMSing – Sources
SMSing – Readme

WebsiteWatcher allows you to monitor a specific (static) website for changes. If the page is updated, you immediately get an SMS message as notification. This tool was initially used to monitor university websites where results of exams were published. Please notice that this simple tool only works for static pages. Clickatell is used as SMS provider. It provides a reliable, fast and cheap SMS-gateway for 578 networks in 192 countries.

Download
WebsiteWatcher – Binaries
WebsiteWatcher – Sources

* * * * * /usr/local/bin/php /home/marc/yahoo.stocks.class.php

and the cron-deamon will execute the script every minute, thus collecting the stock data.

To download the class click right here (do not forget to rename phps to php).

Note that there is no support for this tool anymore.

Download
PHP-RealtimeStats

Additinal download
If you don’t want to download and import the CSV file of IP-to-country download the complete IP-country database mySQL dump from giombetti.com (v 01.04.2004).

DynTEXTMaker