Centralized Multiuser Architecture
Vulnerabilities due to Disasters:- Loss of data in one data base
- Loss of one main (central) processor
- Loss of individual functions at many points
- Loss of applications systems at one point (main)
- Loss of stable, well-supported technology
Client/Server Architecture
Vulnerabilities due to Disasters:- Loss of data in multiple data base
- Loss of multiple servers/processors
- Loss of interdependent functions at many points
- Loss of application systems at many points
- Loss of a wide variety of ever-changing technology
Table 1 on the following page shows that even though the migration to a client/server architecture provides several advantages over a centralized multiuser architecture, the same technological advantages may become significant disadvantages in the event of a disaster, if appropriate disaster recovery and business continuity plans are not made.
Disaster Recovery
& Business Continuity Considerations
for the Client/Server Environment
& Business Continuity Considerations
for the Client/Server Environment
Business functions implemented in client-server environments may be severely impacted by natural disasters such as tornadoes, earthquakes, and hurricanes, or by man-made disasters such as fire, power outage, and equipment failures. Most of these disasters are unpredictable and may occur at any time without any prior warning. Being prepared to handle these situations is imperative in most organizations in order to ensure survival and business continuity subsequent to a disaster. Client/server environments, implemented on local, metropolitan, and wide area networks (LAN, MAN, and WANs) pose particularly challenging problems for disaster recovery and business continuity.
Challenges in client/server environments include the following characteristics that distinguish these environments from traditional, legacy systems, such as a centralized multi-user architecture. See table 2.
Disaster Recovery
& Business Continuity Planning:
& Business Continuity Planning:
Some Strategic &
Operational Considerations
Whether an organization implements a centralized multiuser architecture or a client/ server architecture, there are some fundamental strategic and operational considerations that are essential for disaster recovery and business continuity planning. These considerations are organized as follows:
Strategic Considerations: Organizations need to recognize how critically dependent they are on information processing versus information utilization. This distinction is essential in order to emphasize information processing versus information utilization in the DRBC plan. An organization’s critical need in the event of a disaster may be to recover information processing, which may include the combination of one or more processors as well as telecommunications. An example of this type of an organization is a firm which provides outsourcing services, which are critical for a large number of its customers. On the other hand, an organization’s critical need may be business recovery operations, such as order-taking and order entry in a mail-order firm, where the recovery of business operations utilizing information has a higher priority over information processing per se. In these cases, the recovery of operations takes precedence over recovery of information processing. Note that in both cases, communications, both voice and data, are critical needs for business recovery and continuity. This dichotomy is shown in Figure 1 on the following page. It should, therefore, be clear that business impact analysis (BIA), as the foundation for disaster recovery planning, must include these strategic considerations.
Operational Considerations: Contextual DRBC Development
When organizations decentralize their computing resources, such as in a client/ server environment, it is possible that many client/server networks may all be connected to a mainframe processor consisting of one or more enterprise-level data bases or data warehouses. This type of decentralization also creates the need for contextual development of disaster recovery and business continuity plans, as shown in Figure 2 on the following page.
Concluding Remarks
Distributed computing and client-server environments present unique challenges to the business continuity professionals. While technical challenges can and should, in most instances, find many existing and developing solutions in the disaster recovery industry, strategic, managerial, and operational challenges must be examined from the perspective of the essential support by technologies for organizational mission and core competencies. In this context, developing cost-effective disaster recovery and business continuity strategies requires that the professional business continuity planners and senior managers collaborate on "contextual development of DRBC strategies" to leverage "the type of critical dependency on technology: information processing versus information utilization."
Dr. Raja Iyer, Ph.D., CBCP, is Business Development Manager with Sprint Paranet (Dallas Fort Worth Area), a leading provider of network management and disaster recovery services. Dr. Iyer also serves as a member of the Certification Board of DRI International, and has taught the DRI certification courses for the past five years through out the United States and Canada. He has published over 50 articles in leading professional and academic journals and provided DRBC consulting services worldwide. Dr. Iyer currently serves as an Adjunct Professor of Information Systems at the University of Texas at Arlington.




