Systems Architecture: Product Designing and Social Engineering Rebecca E. Grinter Bell Labs, Lucent Technologies 263 Shuman Blvd Naperville, IL 60566 USA [email protected] http://www.bell-labs.com/-beki ABSTRACT structure - of what was being designed. The role of The production of large and complex systems usually architect evolved to fill that gap. requires the coordination and collaboration of many At the same time as the role of architect was being individuals spread among numerous divisions of a established within some corporations, software architecture corporation. However, much research examining emergedas a researcharea. Software architecture researchers coordination has focused on the subtleties of interactions have focusedon a number of topics including architectural between individuals who may work together in the same description languagesfor expressing the design, codifying department. In this paper, I present a study of systems architectural experienceinto principles, and domain-specific architects and the work that they do to coordinate design frameworks with formal methods for reasoning about acrossorganizational and institutional boundaries. I also architectures[ 13,251. describethe processesand tools that the architects use to support their work. The implications of the social While much of the research in software architecture has processesinvolved in coordinating the design of large focusedon the outcome of the process - the architecture complex systemson the product and those involved in its itself - there is an increasing concern being shown for production are discussed. understandinghow architecturework happensin practice [ 1, 131. One reason why there has been a turn to Keywords understanding practice is it is often the relationship between Systems architecture, empirical studies of design and the design and the organization that presents challenges. development, grounded theory, coordination and As one architect in a computer company explained: collaboration.. The job (of architect} isn’t so much thinking up 1 INTRODUCTION new architecturesbut getting them accomplished. The production of large and complex systems usually That’s the larger part of the effort. Lots of people requires the coordination and collaboration of many have intellectual architectures and not too many individuals including developers, marketing staff, standards people can translate those info actions and experts, and customer representatives. Often, these agreement and creation, that’s really where the individuals are often spreadamong numerous divisions of a rubber meetsthe road. corporation. This paper focuses on one aspect of that production: the early stages of design known as Bass, Clements and Kazman [l] highlight the relationship architecture. Specifically, I examine the how architects between architectureand the organization that produces it in coordinate the design of systems across organizational something they call the architecturebusiness cycle. They boundaries. identify a number of influences on the process including the development organization, the customer organization, any The role of architect is relatively new especially when it maintenanceorganizations, the technical experience of the comesto software design. However, the idea of an architect architects, and the technical environment itself. has evolved from an older profession: systems engineering. In the late 1980s it was perceived that something was The processof building architecture also reveals these kinds missing from systems engineering, an attention on the up of influences on design (for example [3, I 11). For example, front part of the process[22]. Specifically, it was perceived there are clients who drive the design process through their that the source of failure in many systems was that no one fmancial support, governmental organizations that regulate was explicitly focusing on the overall architecture - the shape, height, and placing of buildings through laws, permits, zones, and so forth, and the architecture profession PermisSiOn to make digital or hard copies of all or part of this work for itself that sets standards for design, and encourages Personal or classroom use is granted without fee provided that copies ere not made or distributed for profit or commercial advan. innovations. This design context spans organizations and tage and that copies bear this notice and the full citation on the first page. even countries through the context of financial, legal, and TO copy otherwise, to republish. to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. professionalattachment. WACC ‘99 2/99 San Francisco, CA, USA 0 1999 ACM 1.58113-070.8/99/0002...$5.00 Systems architects face similar challenges, but little is known about how they manage them, and how they 11 produce technically working and organizationally workable going over an hour. Each interview was subsequently designs. Empirical studies of engineering design work transcribed. I used grounded theory - a method for have often taken a different focus looking what happens developing theories from qualitative data - to analyze the during meetings [7, 17, 201 and individuals’ design work data [ 141. The grounded theory approach uses cycles of [24]. Other studies have highlighted the challenges of the data gathering and analysis to develop an understanding of overall development process of which design forms one what is taking place and why. These cycles involve component [2, 9, 121, and how tools support their work collecting data, breaking it down into conceptual units, [15]. More recently, studies of design have begun to reassembling the parts into a substantive explanation of explore the challenges in coordinating work across why events occur, and then using the current understanding organizational and geographical boundaries [ 10, 193. to drive the next phasesof data gathering [27]. This paper builds on these studies by drawing on their The secondphase of the study consisted of following three insights about how design happens. However, it also architectureprojects. The projects selected were designed follows the example set by studies of building architects to to be a cross-section of the work going on, but were all expand the analysis away from the design work done by a small projects so that it would be possible to observe a team of individuals sharing common goals, to examine the substantial amount of the process unfolding. After heterogeneousnetwork of actors who shape the design of following each of the projects to conclusion, I wrote up a the architectures. In the next section, I introduce the report describing architecture work and sent it to subset of methods used to collect and analyze the data and site of the architects I interviewed for their comments and feedback study. The following sections discuss how and why the as a way of verifying whether I captured their work architects studied bring a wide variety of participants into practices. the design processand describe the technologies they use to 2.2 Site support their work. I conclude by arguing that these The data in this study are drawn from two departments of architects coordinate the work of multiple groups and that architects that work for a telecommunications equipment they do this by negotiating in an ever-changing vendor. The telecommunications domain has some environment. unusual characteristics that influence the character of the 2 THE STUDY products designed. First, reliability is critical in voice 2.1 Methods networks, and so designs have to provide fail-safe The focus of this study was understanding how one procedures, minimize downtime, and so forth. Second, corporation’s architects go about their design work, which most telecommunications systems have real-time led to a choice of qualitative researchmethods [IS]. The performancerequirements. Both reliability and real-time study itself consisted of two data gathering phases. The requirements can often stand in conflict with other first phase involved interviewing the architects. Initially I principles of good design, and part of architecture work conducted a group interview with three of the architects. involves resolving those issues as favorably as possible. The purpose of the interview was to elicit information Other characteristicsof the telecommunications domain that about the range of their activities, the people that they architects work with come from customers and regulators. interacted with, the history of their department, their place First, many of the products are configurations of smaller in the bigger organization, and other information of interest. hardware and software components that customers can The information gathered from the group-interview was purchase collectively or selectively. Further, customers used to devise a guide for the semi-structured interviews. expect to be able add more pieces to their .products over The guide developed focused on three important time. Second, telecommunications products also need to componentsof their work: be designed to work with the phone systems of many countries that have different standards. Third, the l questions about what architecture is; telecommunications market has been changing rapidly with l descriptions of the work that the architect does in the the growth of the Internet, deregulation of monopoly departmentincluding a typical project life cycle; and markets, and growth of wireless technologies. Not only is l details about the resources