Journal of Systems Integration, 10, 329±354, 2001 # 2001 Kluwer Academic Publishers. Manufactured in The Netherlands.
Implementation of the Telecom Management Network (TMN) at WorldComÐStrategic Information Systems Methodology Focus KEN DICK
[email protected] Telecom Cluster, College of Information Science and Technology, University of Nebraska at Omaha, Omaha, NE 68182 BONGSIK SHIN
[email protected] Information and Decision Systems, College of Business Administration, San Diego State University, San Diego, CA 92182 Abstract. The telecom industry is experiencing massive technological changes in which a new technology today quickly becomes an old one tomorrow. Telecom Management Network (TMN) was developed as a network management framework to enable innovative management of telecom networks. It is a reference model that provides a uni®ed framework for administration, operation, management and makes provision for services in today's complex telecom environment. It is an innovation that requires the re-engineering of organizational structures, procedures, and even cultures. This study investigated WorldCom, the global telecom powerhouse that has established TMN as the backbone of their long-term business strategy. One of the authors participated in the project, as a key ®gure throughout the planning and implementation cycle. The focus of this manuscript is on capturing the methodical approach WorldCom adopted to revitalize information systems planning and implementation based on the TMN framework. The alignment between the technological architecture and business goals at an organization constitutes the main theoretical basis of the study. Relevant discussions are made on the TMN framework as a general business model for telecom industry, on the functional relationship between integrated systems (IS) and business organizations at WorldCom, and on the motivational factors that triggered TMN adoption at WorldCom. Also discussed are detailed descriptions of information (data) and technical architectures de®ned on the basis of TMN model and different approaches taken for integration and migration of existing systems. Finally, lessons learned from the TMN implementation are discussed. Keywords: Telecom Management Network (TMN), systems integration, IT strategy, technology architecture
1.
Introduction
The telecom industry is experiencing massive technological changes in which a new technology today quickly becomes an old one tomorrow. Likewise, telecom networks are becoming more intelligent, distributed, and larger every day. Voice services are giving way to data and multimedia, low-speed transport is losing out to high-speed networks, closed architecture is being replaced by open standards, closed access is bowing to open access, and integrated systems (IS) are supplanting equipmentspeci®c con®gurations. Furthermore, new networking opportunities from Internet and intense global market competition caused by industry deregulations are fueling cross-
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border mergers and acquisitions on a massive scale and making the business more volatile. Telecom service providers (or telcos) keep adding new services to reduce business risks, to capitalize such strategic opportunities, and to increase revenue. Their goal is to excel in competition and to be able to provide quality services to prospective customers at low cost. The basic business principle mandates is that service providers must be ef®cient in their internal operations and must be ¯exible enough to quickly adapt to new technologies and ever-changing customer demands. It also requires that investment, system development, and management activities be effectively geared to these ends. Such technological and non-technological factors are making effective network management of telecom service carriers complex but critically important. Accordingly, telcos should establish a management system with a holistic view of their operational network to stay ahead of the rapid changes. This becomes more dif®cult when much of the organizational growth is fueled by acquisitions. The merging companies are forced to undertake large-scale system integration of their respective support systems in order to provide universally available services in a consistent manner. Telecom Management Network (TMN) was developed as a network management framework for the innovative management of telecom networks. It is a reference model that provides a uni®ed framework for the administration, operation, management, and provisioning services in today's complex telecom environment. It de®nes a functional hierarchy in which management objectives are broken down into four clearly de®ned logical layers of management: business, service, network, and element. TMN, in this sense, is a body of standards that de®ne the functions and capabilities of the different levels of telecom management and their inter-relationships. Accordingly, organizational adoption of the TMN framework demands a painful paradigm shift in the way business gets done. It is an innovation that requires the re-engineering of organizational structures, procedures, and even cultures. It constitutes an effort to respond to the highly competitive telecom service market that forces frequent and faster business innovations. This study investigated WorldCom, the global telecom powerhouse, which has established TMN as the backbone of their long-term business strategy. The focus was on capturing the approach WorldCom adopted to revitalize information systems planning and implementation based on the TMN framework. The manuscript is organized as follows. After the introduction in Section 1, Section 2 brie¯y introduces competing business models (TMN, TOM, and TINA-C) available for telcos and offers a detailed explanation on the TMN architecture. The research method of this empirical study and relevant theories are described in Section 3. Introduction on WorldCom and its approach in designing IS organization are made in Section 4. Section 5 discusses motivational factors of TMN adoption at WorldCom. The methods taken for the information systems planning based on the TMN architecture are discussed in Section 6. Then, three different paths taken for the necessary integration and migration of existing systems are described in Section 7. Important lessons learned during the implementation of the TMN architecture are discussed in Section 8, which is followed by the conclusion.
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TMN as a Business Model
The business model of a company renders a common understanding of the work processes. It is the high-level process architecture that shows the pro®le of major business functions undertaken, their sequence and data¯ow among them [1]. It becomes an operational vehicle for business drivers that include business strategies, critical success factors, and essential business metrics. In business modeling, developing diagrams that are simple and intuitive is an effective means to describe the complex concepts of the business process as a whole. Documentation of the information associated with jobs and collaborations that implement business processes is also performed. The main goal of a business model is the optimization of the whole and not just the individual parts. This aids in understanding that some decisions may have to be made to sub-optimize certain parts in order to achieve greater optimization of the whole. Currently there are three main competing business models for telecom service carriers: Telecom Information Network Arch-Consortium (TINA-C), Telecom Operations Map (TOM), and Telecom Management Networks (TMN). The logical model of TINA-C speci®es modeling concepts for the information, computational, and engineering viewpoints de®ned by the Open Distributed Process standard [2]. Instead of giving modeling concepts for the enterprise viewpoint, high-level requirements imposed by telecom applications are described and considered at the mission level of the service design methodology. It provides the basis for interoperability and reuse of the telecom software and an open platform that supports distributed processing of application programs. TOM stands for Telecom Operations Map. It is a model of how telecom providers can help assure that they are managing their customer relationships in a comprehensive and appropriate manner. There are 15 process components, including such things as quality of service, con®guration, inventory management, and data management. These 15 components are positioned on a grid. The dimensions on one axis are ful®llment, assurance, and billing. The dimensions on the other axis are customer care, service development and operations, and network planning and development. As an example of the positioning, inventory management is related to network planning and development. This involves both ful®llment and assurance. Likewise, data management is related to network planning and development, and involves both assurance and billing. TMN was introduced by the Network Management Forum (NMF), which is a work group under the International Telecom Union/European Telecom Standards Institute (formerly CCITT). TMN has begun to receive increasing attention from telecom industry as businesses model for the long-term IT planning and deployment. Its emerging importance was well recognized when TMN was selected as one of ten hottest issues in telecom [3]. TMN provides uni®ed management framework for the administration, operation, management, and provisioning services in today's complex telecom environment. TMN de®nes the functions and capabilities in different levels of communications management and how they all inter-relate [4, 5] (Figure 1). It was meant to promulgate ¯exibility, scalability, manageability, reusability, and ef®ciency of telecom management by de®ning detailed implementation requirements.
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Figure 1. TMN pyramid.
The business management layer (BML) manages overall as well as speci®c business goals for an enterprise such as high-level business planning, product planning, budgeting, asset management, legal and regulatory support, external relationships and legal arrangements, return on investment, market share, employee satisfaction, community, and environmental goals. It is responsible for achieving optimal investment and use of new resources. It normally carries out goal setting tasks and supports the decision-making processes rather than goal achievement. The service management layer (SML) deals with managing services offered to customers such as meeting customer service levels, service quality, cost, and time-tomarket objectives. This is the basic point of contact with customers for provisioning, accounts, quality of service, and fault management. This layer is also the key point for interaction with service providers and with other administrative domains. It maintains statistical data to support quality of service etc. NMF sub-divided this into three sublayers of ``customer interface management,'' ``customer care,'' and ``service/product development and operations'' (see Appendix 1). The network management layer (NML) manages the networks and systems that deliver telecom services. It handles the maintenance of network capabilities, the preservation of statistical logs or other data about the network, and the interfaceing with the SML on performance, usage, availability, etc. It has the ®rst ``managed view'' of a network. Five main processes are de®ned in this layer: network planning and development, network provisioning, network inventory management, network maintenance and restoration, and network data management. The element management layer (EML) is responsible for managing the elements comprising the networks and systems such as switches and transmission systems. This is done mostly through actual network element data from logs and activities. This layer controls and coordinates a subset of network elements (either collectively or on an individual basis) to support interaction between the NML and the network element layer (NEL) and perform mediation. This contains ®ve management activities as a form of fault management, con®guration management, accounting management, performance management, and security management.
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Finally, the NEL deals with telecom equipments and any item or groups of items considered belonging to the telecom environment. Routers and switches are the representative items. 3.
Research Method and Theories
This study intends to address implementation approaches [6] that were taken for the deployment of the TMN business model at WorldCom. One of the authors participated in the project as a key ®gure throughout the planning and implementation cycle. His position during the tenure at WorldCom was the Director of Strategic Enterprise Direction. He was involved in all major technical initiatives at WorldCom that included the design and implementation of the technical enterprise architecture. As a consultant for all large-scale systems projects at WorldCom, he reported directly to the CIO. Since the author in¯uenced the outcome of the project, this study belongs to an action research. TMN directs design and deployment of IT in the telecom industry to effectively support business goals and processes. It is a strategic innovation to improve the organizational effectiveness on a long-term basis rather than a remedy that solves shortterm problems. Naturally, both innovation and the alignment between IT architecture and business goals constituted theoretical bases of the study [6±9]. Adoption of TMN ®ts to the frame of organizational innovation. The innovation perspective enables a broad view of the relationship between an organization and the adoption of TMN [10]. Innovation is ``an idea, practice, or object that is perceived as new by unit of adoption'' [9]. TMN is an innovation that brings changes in the organization's structure and business processes. It is a planned strategic organizational change that responds to the internal or external opportunities and challenges resulting from the rapid development of communication/networking technology, telecom industry deregulation, and globalization of telecom service. Many innovation theories assume that identi®able stages exist in the life cycle of organizational innovations [9±13]. Despite the slight differences, they generally share initiation, adoption, implementation, and institutionalization as the common stages. Initiation of an innovation involves processes such as awareness of the innovation, matching with organizational needs and appraisal of trade-off [13]. Naturally, awareness of TMN bene®ts and the effective matching with organizational problems or strategic opportunities will increase the chance of its initiation. Adoption of an innovation such as TMN requires an in¯uence for the decision-making [13] and management support constitutes a primary in¯uencing force at this stage. At the implementation stage, implementation details for TMN would be decided by re¯ecting organizational contingencies. When management and employees successfully adapt to the TMN paradigm, it becomes routine and institutionalized at an organization [10, 13]. As another appropriate theoretical basis, the alignment between business strategy and IT strategy requires that the IT mission, objectives and plans support the business mission, objectives and plans [8]. It emphasizes the importance of linkage [8] and ®t [14] between the two. IT planning and deployment should be carried out so that (1) the business scope is internally aligned between its elements; (2) all internal business units
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are aligned with each other; and (3) the internal business functions are aligned with the needs of the external marketplace [15]. IT architecture should reinforce the effectiveness of business strategy and the business strategy should drive the continual evolution of IT architecture. Information system planning is a process that the business strategy/goals of a ®rm is (are) translated into IT strategy [16, 17]. Boar [15] suggested that, as IT improves its state of alignment, it passes through four stages of business impact: functional automation, cross-functional integration, process automation, and process transformation. He also emphasized importance of IT in supporting business through maximum reach (anyone or any processor, any time or anywhere, can access authorized IT resources), maximum range (all information objects such as information, process or services can be shared), and maximum maneuverability (i.e., scalability, adaptability, and ¯exibility). Venkatraman [18] characterized the degree of alignment in terms of localized exploitation, internal integration, business process redesign, business network re-design, and business scope re-de®nition. Henderson and Venkatraman's [14] model further expanded the alignment scope by emphasizing the ®t and functional linkage among business strategy, IT strategy, organizational infrastructure and processes, and IT infrastructure and processes. 4. 4.1.
WorldCom Company Background
WorldCom is an international telco that offers both wholesale and retail telecom services for local, long distance, data transmission, and Internet access. The company has rapidly grown to its current size as a result of 40 mergers and acquisitions in ®ve years, which included UUNET, MFS, CompuServe/AOL ANS and Brooks Fiber. Gaining MCI has created the approximately $40 billion behemoth MCI/WorldCom Inc. that vastly changed the landscape of global competition in the telecom industry. This case study is based on WorldCom before its merger with MCI. Through the constant mergers and acquisitions, WorldCom rapidly increased its market shares in traditional local service, long-distance service, data services, and Internet access. Its growth in Internet services has been spectacularÐit acquired three large Internet backbone providers (UUNet, ANS, and CNS) making it one of the largest service providers with approximately 23% of total Internet service provider (ISP) connections. It also owned ®ve Network Access Points (NAPs), including two public NAPs in East and West that provided major interconnections between smaller backbones and the major national networks [19]. One of the keys to making an acquisition successful is the seamless assimilation of the acquired company [20]. In order to optimize the synergy effect, the support systems between two old companies have to be quickly integrated and products/services overlapping has to be addressed. The redundancy resulting from the series of acquisitions can not only create confusion among customers but also engender inconsistencies in available products/services and account management. Dif®culties in the consolidation of systems, services/products, customer accounts can create much trouble in the service
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provisioning, installation, and coordination [21]. Naturally, large-scale mergers need to start with a well-de®ned, common business model that all individuals in the new entity will understand business focus and operations [22]. WorldCom's main business strategy was to be a facility-based provider of end-to-end services for local, long distance, data, and Internet access. This would allow WorldCom to provide one-stop shopping to serve the global market where international enterprises were pressing for a single source for telecom services. It also consolidated different types of services so that they could be delivered via one account set-up regardless of residential or business customers (e.g., On-Net service). Internally, WorldCom maintained a single inventory policy so that different business units could sell the same products/services from a common network inventory to different customers. The common inventory consisted of the elements utilized in the network to deliver the basic service building blocks for producing the products and services sold to customers.
4.2.
IS/IT Organization
The focus of IT management should be on attaining functional ¯exibility of the organization through tight alignment of IT and business operations [7]. The IT function of WorldCom was centralized, with dotted line reporting to the business units so that centralized IT management could be in touch with each disparate line of businesses (Figure 2). For this, a vice president/director level IT group that was responsible for each business unit/function was created. It reported directly to the CIO and had a dotted line relationship to the business unit supported. Certain IT support functions that were not speci®c to any business unit (e.g., data center operations, internal data communications, data management, system architecture etc.) reported directly to the CIO.
Figure 2. IS organization.
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With this organizational design, WorldCom was able to maintain consistency in information systems deployment and management. People in each IT group negotiated with the central IT authority to meet the needs of their internal IT customers. The tension to keep a degree of architectural purity was always balanced against the business need, with the business taking top priority. This approach overall enabled tight and continuous integration between the IT function and the business operation in which business strategies and information system strategies could be developed concurrently and reciprocally [23, 24]. The organizational approach in information systems planning [6] forced tight alignment of organization-wide IT strategy with each business unit. The internal standards of information systems should be ¯exible enough to address a wide variety of situations and needs [15]. The ®rst step is to establish a common and high-level view of the business that is acceptable across the enterprise. At WorldCom, this high-level view was accomplished by adopting the TMN model, where each component of the model was mapped to an internal business unit. With the deployment of the TMN framework, everyone knew their sphere of responsibility and their points of interaction with other units. It also helped de®ne the rules for that interaction. The business unit (and associated IS organization) could not dictate broad new standards in an ad hoc manner. When there was tension between a business group and its IS group, it was managed by a small group of IT professionals that had direct reporting responsibility to the CIO. This group was often referred to as the organization's ``technical consciousness.'' WorldCom's information systems approach was to leverage common systems and ensure that when the system was turned up to production, it was ready for operation. For this, it established a few core systems, such as inventory, call mediation and rating, provisioning etc. to support the enterprise. New services and products were worked into these systems. Hence, WorldCom would enter markets with minimal additions to its system inventory. The responsibility of system turnover was in the operations department to increase system stability. Operations department was held accountable for the stability of all the software running in the data center. This had the potential of creating an adversarial role between the applications developers and the operations organization. Through much work and cooperation, this set up provided WorldCom with a fairly stable operating environment. 5.
Motivations of TMN
While the TMN model does not provide a detailed description of business system implementation at a company, it does provide a framework to divide functional responsibilities across business processes (both automated and manual) in a consistent manner. The planning and implementation of information systems based on the TMN is, therefore, expected to facilitate dynamic stability [25] in the organization though better integration vertically and horizontally. An enterprise with the TMN in place can cope with quickly changing markets and products though better horizontal, cross-functional and cross-organizational ¯ow of information [25]. WorldCom adopted a business model that was derived from TMN (Figure 3). The company segmented its business units based
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Figure 3. TMN layers and IS organization at worldcom.
on customers (e.g., wholesale, retail, large businesses, small businesses, and ISP) with all units having access to available products and services. The adoption of the TMN not only de®ned roles and responsibilities of constituents but also provided necessary structure to facilitate communication across the enterprise. Information system speci®cation, design, construction, and operation were then aligned with the business model. Naturally, the TMN reference model became a baseline for system requirement de®nition and organizational structuring. It offered a comprehensive methodology that effectively enabled harmonious combination of IT planning with all of the organization's hierarchical levels and with overall business and corporate strategies [26]. With TMN, WorldCom could establish a baseline of common terminology for all employees. All new project proposals were required to use the terminology to de®ne the functional role of the proposed system(s) within the TMN framework. As discussed, the TMN model is comprised of management layers with each layer representing a portion of the functional architecture of the telecom operations system. Figure 3 shows the relationship between the current information services and engineering development organizations in terms of TMN layers at WorldCom. Engineering's focus was on the network element and its interface into the EML. The focus of information services was from the EML up into ensuing levels of the TMN architecture. This made the EML the point of exchange, cooperation, and coordination between the two organizations. This is where the common functionality was de®ned and where interfaces were created to allow any new network element to plug into the existing network fabric. The standard procedure was to acquire the element manager from the network element vendor, thus further simplifying the process. The TMN model, with de®ned functions and interfaces, made it possible to require network element vendors to address the needs of the EML.
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The TMN compliant global network management offers other strategic bene®ts [27, 28]. It can signi®cantly cut system maintenance costs by reducing the number of dispatches, by dealing with issues from a centralized control center and by minimizing ``one off'' installations. It offers improved maneuverability in the allocation of available bandwidth, introduction of new services, and recon®guration of affected network devices. Network capacity can be dynamically moved to services that are drawing the greatest demand or are producing the greatest margins. A service provider can lower the cost of equipment acquisition by considering multi-vendor products that support the standard. This ¯exibility allows for a multi-vendor network and facilitates competitive biding for the network elements. More effective re-routing of customer data becomes possible because of enhanced network availability and cross-network compatibility. By comparing the TMN layered operational support system (OSS) environment to the typical OSS environments today, any missing applications and systems to support business needs can be identi®ed. For example, the logical partitioning of the billing process identi®es the need for systems to perform the task of call record management that is network element independent. Finally, investment on hardware elements guarantees longer life expectancy. TMN rendered a consolidated view (micro and macro) between service customers (market focus) and available technology (technology focus) by de®ning them as a hierarchical relation (Figure 4). For this, the business model was divided into customer facing, network-facing models to focus on managing the translation between technology focused network-facing systems, and market focused customer-facing systems. The customer-facing model focused on presenting customized products and billing options to subsets of customers divided by market segments: commercial, wholesale, national, and
Figure 4. TMN strategy and hands-off between LOBSS and OSS.
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international. The network-facing model focused on monitoring and controlling network technology while providing a cohesive representation of this technology for use by the customer-facing model. The provisioning and mediation functions represented the demarcation between these two models. Here, the market focus and the technology focus changed at different paces. In fact, business competition was changing faster than IT in the telecom marketplace was. TMN facilitated understanding of what was customer facing and what was network facing (e.g., where there is greater ¯exibility to the customer and where there is limitations of technology) and WorldCom was able to respond to each at the appropriate time. Line of business support systems (LOBSS) were line of business speci®c and differing line of businesses had differing needsÐone size did not ®t all. Therefore, multiple customer-facing systems were needed (e.g., customer care, revenue), but the OSS was the same across the enterprise because all services were selling out of the same bucket. There were other situational factors that motivated the introduction of TMN as the business model at WorldCom. First, the company was seeking new markets to expand the business and become more competitive. This necessitated that internal operation be aligned and organized to effectively deal with the changing business paradigm. Especially, customers increasingly drive the business relationship by demanding companies to understand/respect their needs and expectations [29]. Movement from product orientation to customer orientation, mass customization, and relationship marketing represent organizational reactions for the chaining business paradigm. From the IT/IS strategy perspective, it would be better to avoid extending existing mis-aligned systems via series of point solutions to address immediate customer needs [30]. Second, increasing deregulation, mergers, and acquisitions not only blurred the relationship with suppliers and customers, but also increased competition and complexity in the marketplace [31]. The 1996 bill passed by the Congress opened up the telecom service market for unlimited competition and created huge opportunities as well as challenges to service providers. The change required corporate ability to anticipate needs of the marketplace and refocus on enhancing a product mix in response to the burgeoning competition. Naturally, the corporate ability to quickly restructure parts or all of the enterprise without losing competitiveness in the process was becoming more important than ever [15]. Having an integrated business model and information architecture was crucial to effectively meet the challenges. Third, there was an increasing demand for operating ef®ciency. When service providers are selling similar products/services to customers just like telecom industry, the advantage of timing could be signi®cant [32]. When engineering introduces new technology constantly, any company that can quickly deploy the technology into the marketplace will be in a position to outperform its competitors. Also, telcos are required to quickly determine the most ef®cient customer contact channels, the best product mix and any new product opportunities. Optimizing and targeting the most pro®table use of available resources in an ef®cient manner is crucial as well. Here, having a consistent framework such as TMN, could enable necessary changes as ef®cient and painless as possible.
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TMN-based IS/IT Planning
The effective alignment of IT/IS to the business at an organization requires systematic planning that evaluates various IT and non-IT factors including business strategy, IT strategy, organizational infrastructure and processes and IS infrastructure and processes [14]. Due to the complexity in translating established business processes to the TMN paradigm, a procedural approach was taken to make the transition smooth and at the same time, more systematic. It included the evaluation of business drivers, de®nition of adequate information architecture, determination of requirements for systems characteristics, formalization of general as well as speci®ed technical architectures that will support the information architecture, and establishment of appropriate migration planning (Figure 5).
6.1.
Business Drivers
The business drivers of IT/IS were assessed; these included long- and short-term strategic decisions, tactical business decisions, marketplace opportunities, regulatory issues, planning challenges, performance goals, and competition and supplier issues. For the long-term strategies, outlines of global business model, principles of business management, growth strategy in different product categories, stakeholders (e.g., customers, shareholders) relationship, market strategy, product strategy (e.g., diversi®cation, differentiation and quality enhancement), and business chain management were
Figure 5. TMN as the driver for IS plan.
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evaluated. Short-term strategic initiatives covered such issues as improvement of the network management capability, development of IS plan and of IS disaster recovery plan, expansion of decision support systems capability, and enhancement of billing effectiveness. Besides, other business views such as the critical success factors and the essential business metrics were captured at the business unit level as well as at the enterprise level. 6.2.
Information Architecture
Information architecture is a high-level map of information requirements that are independent of personnel and technology [15]. It is a data plan that de®nes enterprise level data models, their functions, and processes [33]. At WorldCom, the main focus of the enterprise-wide information architecture was on de®ning the logical information/data ¯ow between customers and the telecom network(s). Its brief description is as follows. Data was collected as business events occurred on the network (see Figure 6). All gathered data was directed through the Mediation system. The Mediation system performed functions to ®lter, format, and forward (i.e., route) event data to downstream subscriber systems. Events were pushed to downstream systems as soon as they were available. In order to route the events to the appropriate subscriber system, Mediation used reference information that allowed the identi®cation of the event with a customer context. This context identi®ed the appropriate line of business (LOB) billing environment(s) for the receipt of the event. The common information used to establish these contexts, such as customer and inventory, was provided in a consistent manner via the domain servers in order to assure accuracy and availability across all business processes. The domain sServers provided an authoritative access mechanism for business reference information. Events routed via Mediation were also pushed to monitoring (i.e.,
Figure 6. Call processing information architecture.
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fraud detection) and decision support systems. The responsibility for long-term storage, rating, and invoicing of business events was delegated to the speci®c LOB supporting environment. Orders were processed within the LOB systems based on customer market (Figure 7). Orders could be for complex products/services that spanned many network technologies or have complex interdependencies. Provisioning was divided into two functional layers. First, each network technology area (e.g., switched long distance) had its own provisioning engine(s) that could communicate with the EML. Second, across the technology-oriented provisioning engines was a provisioning work¯ow environment that managed long running transactions for complex services across multiple network technologies. It created the demarcation between the customer-centric LOB order management facilities and the network-centric provisioning engines. Context information was derived from domain servers for business objects such as customer, inventory, and products/services catalog. 6.3.
Systems Requirements
At this stage, important conditions and characteristics of organizational IT/IS that had to be satis®ed to implement the information architecture effectively, were decided with traceability back to the fundamental business drivers. These conditions and characteristics represented factors that would ultimately improve the ¯exibility [7] of IT/IS at WorldCom. Scalability: Scalability is the ability of a system to grow in its size without changing an application or its data ®les [15]. Especially, it should effectively handle any rapid expansion of database volume. At WorldCom, it was decided that conforming systems
Figure 7. Order/provisioning information architecture.
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must be able to scale ten times today's volumes with little re-engineering of the basic system designs. System of systems: Information systems planning and implementation need to adopt a toolkit approach in which common building blocks can be re-assembled and quickly adapted as business conditions changes and new services are introduced. For this, the number and types of interfaces must be reduced and standardized. Also, methods to leverage existing legacy systems should be de®ned so that they can participate as building blocks in the enterprise wide IT/IS architecture. Information access and quality: Critical information should be available as quickly as business events occur. Systems must be able to respond and operate at the same rates at which business events happen. Information must be consistent across systems and across the corporate to improve responsiveness and quality of customer service and must allow for better decision-making. Support the operational model: The IT architecture must support a common global view of information and controls for operational support and ®nancial functions. At the same time it should enable different lines of business to support their respective customer sets differently in external representations of the systems. Simplicity: Simplify development by using a minimum number of well-understood tools and delivery platforms across projects. Reduce the number of vendor relationships. Simplify development by providing immediate access to critical common data. Simplify system management by engineering in global monitoring and control mechanisms that will allow operations staff to view and manage business processes. Globalization: It is critical that IT architecture and design practices allow for appropriate geographic partitioning. Geopolitics, response time, wide area networks and data-center costs will drive many of these decisions. This means that application services and data management partitioning are crucial. Without partitioning in logical designs, physical partitioning becomes dif®cult; without physical partitioning, it is not possible to partition geographically as business needs warrant. Service management: The IT architecture needs to be able to support a wide range of service levels through design practices and systems engineering. These service levels range from low impact, decision support type systems to continuous operations for business affecting operational systems. Provisions must be made to support disaster recovery strategies as they are needed. Data processing environments: IT architecture must provide for different styles of data processing. The design and implementation of a system that supports billing or network mediation is very different from a system where an employee or customer is interacting directly with an application service. OSS have different characteristics from decision support environments. The architectural model needs to account for these different data processing environments. In addition to the architectural requirements, various rules and principles that guide the technical development of the IT/IS were developed in this stage. Relationships and dependencies between the various IT elements, and roles and responsibilities of IS planners; builders and managers of these elements were de®ned. Best practices for design, implementation and management decisions were established to ensure that a
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common set of principles is maintained to reduce any risks in deploying the enterprise architecture. Rules of engagement were developed to govern the interaction (e.g., information push vs. pull) of disparate processes and systems in the business enterprise. Operations established clear operational requirements for managing information systems in such areas as the con®guration management, process controls, security, audit, controls, event services, and performance. 6.4.
IS/IT Conceptual Architecture
A systematic IS development based on the technical architecture renders a number of bene®ts to an enterprise. It aligns IS/IT investment with business goals and directs effective management of IS/IT resources [6], which can lead to sustainable competitive advantages [34]. It facilitates effective change management by linking strategic requirements to IS/IT planning, designing and development [35]. By improving linkage, interoperability, and modularity among systems, it not only facilitates effective data sharing and strategic use of data resources, but also reduces data redundancy and maintenance costs [15]. It can promote systems openness through a common set of adopted standards. It also improves the quality of software development and facilitates building a responsive and ¯exible IS/IT infrastructure [7]. Without the common wellunderstood architectural model, developers will either invent total solutions from scratch or build variants of earlier work that may not be consistent with long-term business and IT strategies [36, 37]. For this, a high-level conceptual IS/IT map was designed and detailed principles and requirements for deploying each component within the map were introduced. The conceptual map was composed of 11 architectural components that represented particular functions and applications of the IS/IT infrastructure (Figure 8). The components were conveniently divided into data (or information), application, and infrastructure categories. Guidelines for objects, transaction data, and data warehousing belong to the data architectural category. The object architecture is the internally consistent set of relationships between business-relevant entities that de®ne how real world ``things'' (e.g., invoices, orders, products, customers etc.) interact and describe expected behaviors from each object class. The transaction data architecture, as a subset of the enterprise's overall data architecture, represents those relevant to operational activities that must be recorded and accounted for in a business information environment. The data warehouse architecture provides the standards for accessing decision support and on-line analytical processing (OLAP) data. The application category details architectures of applications, collaborative/work¯ow, middleware, and systems management. The application architecture de®nes the development strategy of how applications are designed, how they cooperate, and where they reside to enable a high level of distributed system integration, reuse of components, rapid deployment of applications and high responsiveness to changing business requirements. The collaborative/work¯ow architecture de®nes the environment for automating conversation-focused and activity-focused aspects of human/computer
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Figure 8. Conceptual architecture and components interactions.
interactions and human behavior. The middleware architecture determines the components that create an integration environment between the user workstations and legacy and server environments to improve the overall usability of the distributed infrastructure to the user. The systems management architecture describes how the hardware and software components will be controlled in terms of con®guration management, fault detection and isolation, testing, performance measurement, problems reporting, and software upgrades and control. The infrastructure category elaborates details of platforms, Intranet, e-commerce/ Internet and network architectures. The platform architecture de®nes the technical components of the structure, including the client and server hardware platforms, the operating systems used and the database environments, and interfaces supported. The Intranet architecture deals with issues of internal business communications and access to business information. The e-commerce/Internet architecture addresses the technologies, standards and guidelines for seamless, platform independent, inter-enterprise business communications, and global access to business information. The network architecture provides the communication infrastructure for the distributed computing environment and consists of logical elements (e.g., structure, topology, bandwidth, management), physical hardware components (e.g., wiring, LANs, hubs), carrier services (e.g., frame relay, leased channels, ATM), and protocols (e.g., access routing, naming). Reference information regarding the main interactions among primary components was also de®ned (see Figure 8). Primary interactions in the symmetric matrix indicated that selected components were closely associated at WorldCom and their cross-referencing during the system planning and implementation was crucial. Once the high-level IS/IT architecture was completed, each architectural component was elaborated in terms of
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1.
Design standards that guide IT decision-making;
2.
Agreed upon technologies for implementation;
3.
Policy and industry standards adopted within its IS/IT organization; and
4.
Products and sample con®gurations that illustrate the application of the agreed architectural principle.
By containing such common set of principles and speci®cations, the technical architecture provided holistic guidance in the design, selection, construction, implementation, deployment, support, and management of information technologies. On the completion of the architectural details, migration approaches were de®ned to move or adapt existing systems to the new environment governed by the uni®ed IS/IT architecture. 6.5.
Migration Planning
Three main activities were de®ned in the stage of planning for system and architectural migration. First, as an initial step, analysis was done to determine the difference between where they had been and where they were collectively heading. In the gap analysis, an ``as-is'' model of existing IS/IT environment was produced and an attempt was made to understand the amount of time, money, and effort that would be required in order to implement systems based on the new architectural paradigm. Second, documentation was made on projects and project phasing required implementing systems within the new enterprise-wide architecture. In addition, roadmap phasing and critical interdependencies between projects were identi®ed. Third, organizational issues that the migration would inevitably create were addressed as a form of change management for employees. These issues included the documentation of new roles and technical skill-sets needed, recommendations to minimize negative reactions and re-enforce positive behavior and establishment of programs and necessary training to familiarize staff with elements of the technical architecture. 7.
Systems Integration and Migration
The company adopted three different strategies for the necessary integration and migration of information systems under the new technology architecture: handshaking, borrowing, and translation. The choice of the strategy was based on the data dependence inherent in the existing systems. For those systems where the data and associated rules were buried deep within the system, the handshake approach best expedited the migration (Figure 9). Handshake integration strategy is the easiest way of system migration. This approach enables combined functionality by building a duplicate ``live'' copy of common data in both systems. It, therefore, requires constant synchronization and
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Figure 9. Handshake integration strategy.
exchanges of control and, depending on system logic, updates may be required at multiple levels. Also, storage requirements may double, and data integrity issues are usually impossible to solve. It, therefore, works only when there is little overlap between systems and systems are small scale (since integration is complex and sometimes manually intensive). In that sense, although promoting rapid startup, it lacks sustainability and scalability. It also does not facilitate migration or reuse, but instead increases dependence on combined ``system'' by retaining all existing interfaces. Where data and associated rules were more easily accessed, but yet were still embedded in the system logic, the borrowing strategy was most suited (Figure 10). Borrowing integration strategy delineates system functionality and, therefore, can consolidate interface, but it is not sustainable as a migration strategy. In that sense, it is a better approach than handshake but is also a relatively harder strategy. This approach allows one system to be the source or lender of data and have the other system borrow it as needed, usually in batches. It typically involves modi®cations to lender in order to collect batches of data or provide for updates. This mode of integration, however, does not work well unless there is clear separation between existing functions in the lender and new requirements in the borrower. In addition, it does not work well if there are multiple borrowers since data integrity cannot be maintained while data is ``lent out''. This does not facilitate effective migration because data is not permitted to move permanently away from the lender; it requires ``big bang'' to move. For those systems where clear logical partitioning existed, it was possible to simply translate formats for the downstream existing systems (Figure 11). Translation integration technology establishes priorities of system partitioning and begins with sustainable migration strategy. This approach ®rst carves out coherent chunks of the database with related functionality and translates from old interfaces to capture data into new data store
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Figure 10. Borrowing integration strategy.
and allow migration of application functionality in chunks. Migration is then done for users (or their roles) to new or alternate interfaces as functionality evolves. It is dif®cult if legacy systems do not allow access to functions via application programming interface
Figure 11. Translation integration technology.
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(API) without user interface. In addition, new applications must use the new data model to promote migration. It supports continuous migration by assuming the existence or introduction of ``old'' systems is ongoing (e.g., via acquisitions). Although translation integration was the best approach from long-term perspective, it was most dif®cult and time-consuming process. Accordingly, compromise was taken as needed to ascertain the fast migration into the new information architecture. The biggest issue in the migration to TMN-based business model was data management. The integration and migration of databases was a challenging process that could cause dif®culties in successful implementation of strategic information systems planning (SISP) [38]. Abstracting the data level, extracting the data and affect how the systems operate, were extremely dif®cult. The centrality of the data was key for the success of systems integration and migration. It required common de®nitions and common source points supporting diverse usage. Clari®cation of data/system owners, users and caretakers immensely helped in effective data management. Each data element was assigned a single owner and a single originating source. This provided for some interesting debates as the organizations sorted out who actually owned and originated the key data elements. At that point, subsequent users of the data could not change the value of the element in any system other than the originating or owner system. This prevented multiple generations of data with variations in the ®eld. It also provided a de®nitive source for all key elements. User systems, if required, could add an additional ®eld to the record, but could not change the original value or use of the key element. The caretaker had the responsibility to ensure that the data was available to the users in a timely, accurate, and usable manner, while protecting the integrity of the data values. This structure enabled WorldCom to increase the integrity of the company's core data elements. 8.
Lessons Learned
The main lessons learned during the implementation of the TMN model are summarized in this section. First, aligning the IT organization to the functional business units meant breaking down certain silos and moving them across departments [35]. Management had to get the rest of the corporation ( particularly engineering and marketing) to agree with the process ¯ow and view of the world. A good example was the approach to multiple billing systems in which each line of business had a speci®c set of needs. These needs put different functional and technical demands on the billing system. The system used to support mid-sized businesses did not have the same requirements as the system to support wholesale. The former had a great number of customers with a smaller number of billable records with less demand for detail. The latter had smaller customer base with an insatiable desire for call detail to support their business. The previous IS organization had each billing system reporting independently up through the chain of command. With that structure, each did what they saw ®t and it ended up with diversity of design and redundancy of certain processing. In the new IS organization, these units reported to a single vice president who could oversee the operations and move towards commonality in design and leverage common processes. These billing groups still had a dotted line
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responsibility into their respective lines of business to ensure that the functionality required by the business was met. This reorganization, with some commonality in design and processing, also allowed for the moving of resources between the billing groups for special projects. For the TMN business model to be successfully implemented, each department had to learn to trust the other departments for the provision of infrastructure, data, processing and others. They had to overcome certain pre-established animosities and biases because con¯icts could signi®cantly affect organizational or team performance in a negative fashion [39]. For instance, in a stove-piped organization, it is convenient for all to claim ownership of all data they use in their processes. Thus, if all have ownership, none have control. The process of de®ning relationships of ``owner, user, and caretaker'' forced the negotiation and mutual interdependence between various business units. It also con®rmed that successful implementation of information systems based on the integrated and holistic business model must address the cultural and behavioral issues stemming from the changes in power [26]. A common set of infrastructure tools and services had to be de®ned. One of the key components to creating and maintaining logical partitions in the application arena is to provide consistent communications between the applications. If organizations are to share data, they need to be able to communicate between applications in such a way that each application has no knowledge of what function the other performs, but has only knowledge of the data. For this to take place, the infrastructure must exist that can facilitate and manage the inter-process communications. This infrastructure should include some if not all of the following: messaging, transaction process monitoring, and object request brokers. The selection will depend upon the architecture of the application environment. In addition, there needs to be a reliable internal network to support the moving of data. To adopt the TMN model, everyone had to agree to a certain logical partitioning of the application arena as well as certain data ¯ows. As an example, call rating was taking place far too early in the process. In the existing system, ¯ow rating was occurring right after the call collection process. In most cases, the calls were being re-rated a second time further down stream where they were assigned to a customer and received special contractual rating and/or discounting. The partitioning of the applications and data ¯ow diagrams accentuated this issue and rating was moved. The concept of single generic operation support systems (OSS) dies hard; but, TMN helped people see that with the number of network elements and with the rate they were changed (independently), it became impossible to maintain a single generic provision system that could con®gure all the various network elements for all the various services. It became clear that a ``system of systems'' was the only feasible solution for maintaining pace of change. Utilizing the TMN model, they could develop a provisioning stream that was initiated by a service order and then broke down into the steps and associated systems as they related to the individual network elements necessary to provide the service. This allowed for a loosely coupled system of systems where additions and changes could be quickly implemented. In order to make this workable, it was essential to minimize the amount of knowledge each component must have of the other components within this system of systems. This
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translated into a concept quickly became one of common inventory and work¯ows feeding multiple provisioning systems. However, it was important to note that the provision systems would be unique by network elements. The key was network inventory and work¯ow. The network inventory contained all elements on the network, both logical and physical, that are utilized in the provision of telecom services. A common network inventory was important because of the fact that certain products and services utilized the same network elements. If separate inventories had been kept, an element could be provisioned twice and yet only used once, producing a con¯ict and a disruption of services. It was important to having people see the whole process, not just their part of it (i.e., think globally while they working locally). They had to see that the optimization of the whole was more important than the optimization of any individual part. That was an educational process to help teams see where they ®t and how what they did in¯uenced the company in total. This was accomplished, in part, through achieving a common consensus on the de®ned work¯ow. Information systems are business enablers and their forms must follow the function and structure of the company. Once the business model is starting to jell, it is then time to start the selection of the surviving systems. It is important in this selection process not to take a ``best of breed'' approach with the systems. The goal is to optimize the processes and their enabling systems across the whole business model. In order to do that some suboptimal system components (due to their functionality, or ease of integration etc.) may have to be selected in order to optimize the overall process ¯ow in the total business model. This principle took some adjustment by certain business units that wanted to always be doing the latest and greatest technologies. People had to start seeing their silo systems in logical parts that ®t into various levels in this model. 9.
Concluding Remarks
WorldCom developed an enterprise-wide information systems architecture that contained both information and technology architectures based on the TMN reference model. For effective delivery of the architecture plan, WorldCom re-organized its IT to line up with business strategies, in which the organization itself was centralized in technology management but it remained in touch with disparate line of businesses. Naturally, the focus of information system speci®cation, design, implementation, and operation was aligned with the business model as much as possible. The TMN model furnished external ``expertise'' by helping in de®ning the requirements, dependencies, and the rules of engagement. The IT architecture built around TMN allowed the IS organization to leverage existing skills and resources while making it responsive to the rapid changes in the telecom market. WorldCom's growth strategy has been through acquisitions. One of the keys to making that strategy viable has been the effective assimilation of the acquired company. In order to fuel the growth of WorldCom in international services, Internet services and domestic services and to continuously achieve the improvements in operating ef®ciencies, the OSS at the company had to be integrated. The architecture built on TMN aided in the
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assimilation of new technology into the fabric as well as new people into the organization. TMN-based IS/IT architecture was shown to be a structural innovation on which planning, deployment, and management of information technologies could lead to a competitive advantage via improved service provisions, reduced cost and procedural redundancies, and better operational ef®ciency and effectiveness.
Appendix 1.
NMF framework (Source: http://www.nmf.org/).
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