CS 599
Current Issues in Software Architectures

Fall Semester, 1999
Location: KAP 147
Time: TTh 2 - 3:30 pm
Class number: 33632
Prerequisite: CS 612 or instructor's consent

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Instructor | Overview | Readings | Assignments | Schedule | News and Announcements

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Instructor

• Nenad Medvidovic
• Electronic Mail: neno@usc.edu
• Office: SAL 338
• Office Phone: (213) 740-5579
• Office Hours: TTh 3:30 - 4:30 pm, or by appointment.

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Overview

Software architecture has become an area of intense research in the software engineering community. A number of architecture modeling notations and support tools, as well as new architectural styles, have emerged. Architectures shift the focus of software developers from lines-of-code to coarser-grained building blocks and their overall interconnection structure. Explicit focus on architecture has shown tremendous potential to improve the current state-of-the-art in software development and alleviate many of its problems. 

However, this is still a young and relatively immature discipline that has failed to adequately address certain important issues. Architecture-based development approaches have often made simplifying assumptions in order to convey conceptual simplicity and flexibility; this has typically been done at the expense of realism and practicality. Examples of such assumptions are: 

• modeled software systems are "one of a kind;"
• software architectures exist in a vacuum, independently of system requirements, lower-level designs, and implementations; and
• preserving architectural properties in designs and implementations is beyond the scope of concern, as is ensuring that changes in a system's design and/or implementation are correctly reflected in its architecture.

Full realization of the potential of software architectures and their transition into the development mainstream will require a more realistic approach, in which systems are both modeled and implemented as members of an application family. This, in turn, requires a deeper understanding of the nature of software application families and the role architectures play in them. It also necessitates practical mechanisms for architecture-based development of application families, which leverage advances in areas like software reuse, software interoperability, or middleware, technologies (e.g., CORBA, COM/DCOM, Enterprise Java Beans), object oriented modeling and analysis (e.g., UML), extensible, portable representation (e.g., XML), and commercial software product families (e.g., Adobe Acrobat, Adobe Photoshop, Microsoft Office). 

This course will focus on the current state of software architecture research and its shortcomings, including its treatment of software connectors, application families, analysis, consistent refinement into implementation, and evolution (both at system specification-time and at run-time). Existing mechanisms and technologies, such as the ones identified above, will be discussed and their applicability to architecture-centric technologies assessed. Possible directions of future work will be identified. The course project will give each student an opportunity to pursue one such direction in more depth. 

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Readings

• Due to its nature, this course will not have a textbook.
• Students will be required to read a number of papers from recent workshops, symposia, conferences, and journals. About half of the covered papers will be short, issue papers (typically 3-4 pages); the other half will be longer, research papers (typically 10-12 pages).
  NOTE: The Department will make copies of the papers and I will distribute them in class in 3-4 installments. To purchase the papers, you must pay $20 to Amy Yung in the front office (SAL 300). Please do so promptly to make the distribution process go as smoothly as possible.

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Assignments

Name	Description	Weight
Presentations	Presentation of read research papers. Each student will be required to present multiple short and long papers during the course of the semester. Presentations of short papers should be 15 minutes long; presentations of long papers should be 30 minutes long. Each presentation should try to answer the following questions about the paper: What problem is the paper trying to solve? What open issue(s) identified in the September 7 lecture does the paper address? What approach are the authors taking? What are the results of the described approach? What are the strengths of this paper? How can the paper and the underlying work be improved?	30%
Class Participation	Paper presentations are intended to generate discussion during the class. This will require students to attend the class and keep up on the readings.	20%
Class project	In-depth treatment (possibly including implementation) of a topic highlighted in class. The project will be conducted by individual students or teams of two.	50%

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Schedule (to be updated incrementally)

NOTE: The first paper listed in each reading-and-presentation set (starting on September 9) is a short paper and the second a full-length paper.

Week	Date	Lecture/Reading Topic	Reading	Presenter	Assignment
1	Aug 31	Course introduction Overview of software architectures (PDF)	N. Medvidovic and R. N. Taylor. A Classification and Comparison Framework for Software Architecture Description Languages. IEEE Transactions on Software Engineering, 1999. (to appear) (PDF)	Medvidovic
	Sep 2	Overview of software architectures cont. (PDF)	N. Medvidovic and D. S. Rosenblum. Domains of Concern in Software Architectures and Architecture Description Languages. USENIX Conference on Domain-Specific Languages, Santa Barbara, CA, October 1997. (HTML or PDF)	Medvidovic
2	Sep 7	Open issues in software architectures (PDF) Initial reading and presentation assignments	N. Medvidovic and R. N. Taylor. Separating Fact from Fiction in Software Architecture. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998. (PDF)	Medvidovic
	Sep 9	Reengineering View integration · Slides unavailable	W. Eixelsberger et al. Software Architecture Recovery of a Program Family. 20^th International Conference on Software Engineering (ICSE98), Kyoto, Japan, April 1998.	McCraley
		Reengineering Representation Refinement View Integration · Slides (PDF)	I. T. Bowman et al. Linux as a Case Study: Its Extracted Software Architecture. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Fisher
3	Sep 14	Connectors Reuse Representation · Slides (PDF)	G. T. Heineman. Adaptation and Software Architecture. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Mehta
		Analysis Middleware Representation · Slides (PDF)	A. Borgida and P. Devanbu. Adding More "DL" to "IDL": Toward More Knowledgeable Component Inter-Operability. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Phadke
	Sep 16	Middleware Reuse View Integration · Slides (PDF)	R. Natarajan and D. S. Rosenblum. Merging Component Models and Architectural Styles. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	McCraley
		Configuration Management Evolution Analysis and Testing Connectors · Slides (PDF)	J. E. Cook and J. A. Dage. Highly Reliable Upgrading of Components. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Rakic
4	Sep 21	Application Families Representation Refinement · Slides (PDF)	D. E. Perry. Generic Architecture Descriptions for Product Lines. 2^ndInternational Workshop on Development and Evolution of Software Architectures for Product Families (ARES II), Las Palmas de Gran Canaria, Spain, February 1998.	Mehta
		Application Families Interoperability Reengineering Configuration Management · Slides (PDF)	D. J. Kasik et al. A Flexible Approach to Alliances of Complex Applications. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	McCraley
	Sep 23	Refinement Representation Analysis · Slides (PDF)	V. Stavridou and R. A. Riemenschneider. Provably Dependable Software Architectures. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Hsiao
		Representation Analysis Styles · Slides (PDF)	M. H. Klein et al. Attribute-Based Architecture Styles. 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	Mehta
5	Sep 28	Project Proposal Preparation - no class
	Sep 30	Project proposal draft presentation and discussion			5-7 minute presentation of a draft of your proposed project
6	Oct 5	Representation View Integration · Slides (PDF)	R. Hilliard and T. Rice. Expressiveness in Architecture Description Languages. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Jeoung	Project Proposals Due (2 pages) What problem will you try to solve? What is the current state-of-the-art in your problem area? What approach will you take? What is your schedule? How will you know when you are done?
		Connectors Interoperability · Slides (PDF)	R. DeLine. Avoiding Packaging Mismatch with Flexible Packaging. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Mehta
	Oct 7	Configuration Management · Slides (PDF)	A. van der Hoek et al. Versioned Software Architecture. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Jeoung
		Representation View Integration Refinement Analysis · Slides forthcoming	A. Egyed and C. Gacek. Automatically Detecting Mismatches during Component-Based and Model-Based Development. 14^th International Conference on Automated Software Engineering (ASE’99), Cocoa Beach, FL, October 1999.	Egyed
7	Oct 12	Representation View Integration · Slides (PDF)	V. Issarny et al. Multi-View Description of Software Architectures. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Yan
		Psychology Organizations · Slides (PDF)	P. Kruchten. The Software Architect – and the Software Architecture Team. 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	McCraley
	Oct 14	Extra-Functional Properties Heterogeneity Interoperability · Slides (PDF)	S. A. Butler. Security Issues with the Global Command and Control System (GCCS). 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	Phadke
		Project Discussion
8	Oct 19	Application Families Process · Slides (PDF)	J. DeBaud et al. PuLSE-DSSA – A Method for the Development of Software Reference Architectures. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Fisher
		Representation View Integration Refinement Analysis · Slides forthcoming	A. Egyed and N. Medvidovic. Extending Architectural Representation in UML with View Integration. Second International Conference on the Unified Modeling Language (UML'99), Fort Collins, CO, October 1999.	Egyed
	Oct 21	Refinement Traceability Evolution · Slides (PDF)	Z. Wang. Architectures Abstraction Tower. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Rakic
		Middleware Traceability Heterogeneity · Slides (PDF)	S. Stuurman. Software Architecture and Java Beans. 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	Jeoung
9	Oct 26	Middleware Architectural Style · Slides (PDF)	A. Carzaniga et al. Issues in Supporting Event-Based Architectural Styles. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Egyed
		Representation Architectural Style Reengineering · Slides forthcoming	N. Roodyn and W. Emmerich. An Architectural Style for Multiple Real-Time Data Feeds. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Yan
	Oct 28	UML'99 - no class
10	Nov 2	Representation Application Family · Slides (PDF)	M. Tanuan. Software Architecture in the Business Software Domain: The Descartes Experience. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Phadke
		Refinement Reuse Evolution Application Family · Slides (PDF)	L. F. Andrade et al. Architectural Concerns in Automating Code Generation. 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	Egyed
	Nov 4	Discussion and Review		Medvidovic
11	Nov 9	Process Economics · Slides (PDF)	K. J. Sullivan. Software Design: The Options Approach. 2^nd International Software Architecture Workshop (ISAW2), San Francisco, CA, October 1996.	Hsiao
		Analysis and Testing Reuse Heterogeneity Evolution · Slides (PDF)	A. Michail and D. Notkin. Assessing Software Libraries by Browsing Similar Classes, Functions and Relationships. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Rakic
	Nov 11	Application Family Reuse Heterogeneity Organizations · Slides forthcoming	J. Bosch. Product-Line Architectures in Industry: A Case Study. 21^st International Conference on Software Engineering (ICSE99), Los Angeles, CA, May 1999.	Hsiao
12	Nov 16	Application Family Representation Traceability · Slides (PDF)	J. DeBaud. Viewing a DSSA in Context: Problems versus Solutions. 2^nd International Software Architecture Workshop (ISAW2), San Francisco, CA, October 1996.	Yan
		Representation Analysis · Slides forthcoming	J. Vera et al. Event-Based Execution Architectures for Dynamic Software Systems. 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	Phadke
	Nov 18	· Slides unavailable	H. Gomaa and G. A. Farrukh. Composition of Software Architectures from Reusable Patterns. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Fisher
		Reengineering Traceability · Slides (PDF)	N. C. Mendoça and J. Kramer. Requirements for an Effective Architecture Recovery Framework. 2^nd International Software Architecture Workshop (ISAW2), San Francisco, CA, October 1996.	Rakic
13	Nov 23	Refinement Analysis Representation · Slides (PDF)	R. A. Riemenschneider. Checking the Correctness of Architectural Transformation Steps via Proof-Carrying Architectures. 1^st Working International Conference on Software Architectures (WICSA1), San Antonio, TX, February 1999.	Egyed
		Course Evaluations		Rakic
	Nov 25	Thanksgiving - no class
14	Nov 30	Case Study: 2K System · presentation of features and issues (PDF)	F. Kon et al. 2K: A Reflective, Component-Based Operating System for Rapidly Changing Environments. F. J. Ballesteros et al. Object-Orientation in Off++ - A Distributed Adaptable Microkernel. M. Roman et al. Design and Implementation of Runtime Reflection in Communication Middleware: the dynamicTAO Case.	Phadke
	Dec 2	Case Study: 2K System · elicitation of the architecture		Phadke
15	Dec 7		A. Ran. Architectural Structures and Views. 3^rd International Software Architecture Workshop (ISAW3), Orlando, FL, November 1998.	Yan
			M. C. Paulk. The Rational Planning of (Software) Projects. First World Congress for Software Quality, San Francisco, CA, June 1995.	Jeoung
	Dec 9		S. Butler et al. The Potential of Portfolio Analysis in Guiding Software Decisions. 1^st Workshop on Economics-Driven Software Engineering Research (ESER-1), Los Angeles, CA, May 1999.	Hsiao
			D. Wile. AML: An Architecture Meta-Language. 14^th International Conference on Automated Software Engineering (ASE’99), Cocoa Beach, FL, October 1999.	Fisher
		Course review, summary, and conclusions	J. Gray. What Next? A Dozen Information Technology Research Goals. Turing Award Acceptance Lecture. Technical Report MS-TR-99-50, June 1999.	Medvidovic
Finals	Dec 13,15				Project write-ups and presentations/demonstrations due

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News and Announcements

NOTE: The announcements are listed from most to least recent.

Date	Announcement
11/16	The final four presentations have been assigned.
10/14	The presentation of the Gomaa and Farrukh paper has been moved to November 16.
10/5	Alex Egyed will do a dry run of his ASE’99 paper instead of presenting the Riemenschneider paper on October 7. The Riemenschneider paper review has been moved to November 16.
9/22	The second set of papers is available for pickup from my office (SAL 338). I will also bring them to class tomorrow (9/23).
9/20	The second set of papers (October 12 through November 11) has been added to the page. They will be available for pick up from Amy Yung’s office (SAL 300) by the end of the week. Please check this page for an announcement before checking with Amy.
9/16	The order of two papers has flip-flopped: the Klein et al. paper will now be presented on September 23, while the Kasik et al. paper is moved up to September 21.
9/13	Comments by Nikunj Mehta on the September 9 papers. (PDF)
9/7	Please make sure to send me a postscript or PDF copy of your presentation by noon of the day you are presenting so that I can put it on this page and make it available to the rest of the class. If you need help with making overhead transparencies from your charts, I can arrange to do that for you provided you make the charts available to me by 10 a.m. of the day of your presentation.
9/5	Slides for the September 7 lecture have been added.
9/3	Similarly to my lectures, you should use slides printed on overhead transparencies for your presentations. If you wish to give an on-line presentation, let me know at least a week in advance so I can try to secure a projector. A good rule of thumb is to plan on spending about three minutes per slide. Thus, you should try to have no more than 5-6 slides for a 15-minute presentation and 10-12 slides for a 30-minute presentation.
9/1	Per our discussion in class, a class period has been set aside on September 30 for students to present and exchange ideas about projects.
8/31	Please email me your name, USC student ID number, and email address. You can volunteer to present a paper either in class or by sending me email. If nobody volunteers to present a given paper, I will assign it to a student. Remember to purchase course readings from Amy Yung in SAL 300.

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Last updated:  12/2/99