Understanding and Deploying LDAP Directory Services > 12. Choosing Directory Products > Categories of Directory Software |
Categories of Directory SoftwareBecause it is difficult to provide all things to all people, software vendors tend to focus their product development efforts on serving specific needs. By comparing a vendor's focus to your directory needs, you can often narrow down your list of candidate products very quickly. Although LDAP is a general-purpose protocol, the needs of one directory deployment may be quite different than those of another. For example, an LDAP server implementation that provides strong security features might be well suited for deployment on the public Internet, whereas another product that provides minimal security may be a great product for small workgroups. These two implementations would thus require different directory software. There are many ways to categorize the available products. One of the most useful ways to sort them is by looking at the various applications they aim to support:
Each of these categories is described in the following sections. Network Operating System ApplicationsFrom the directory software perspective, a NOS is just another application with a specific set of needs. Directories that work well with NOSs are generally focused on basic network services such as logon, access control, and management of LAN services (such as file servers and printers). In most cases, a directory that works with a specific NOS is not separable from the NOS itself, and LDAP is typically grafted onto existing products (although the current trend is toward better support for LDAP and other open standards). For products in this category, integration and ease of management are very important, and performance, scalability, and support for multiple platforms are de- emphasized . Intranet ApplicationsIn recent years , the term intranet has been adopted to describe networks inside organizations that are based entirely on open Internet technology. This trend started with the adoption of Web servers and browsers inside the corporate firewall and has moved on to encompass messaging, groupware, and directory products. Directory software that is suitable for use within intranets is typically designed to support a wide variety of end user and server applications, such as corporate phone books and high-volume messaging servers. Ease of management, performance, and scalability are all important within this category. Extranet ApplicationsThe term extranet is used to describe business-to-business and business-to- consumer communication networks that are based on open, Internet technology. Extranets are almost always virtual networks in the sense that they are typically formed by making secure connections over public networks such as the Internet itself rather than by pulling cable. Extranets are gaining momentum because they can be used to deploy completely new applications and replace expensive, proprietary electronic data interchange (EDI) networks. Extranet directory-enabled applications typically serve very large numbers of people. In addition, many of the people served may not be directly employed by the organization that hosts the application. For example, extranet applications often connect manufacturing organizations to their suppliers. This leads to a need to store information about people who work for both the supplier and the consumer (the company hosting the extranet application). This kind of extranet procurement application is shown in Figure 12.1. Figure 12.1 An extranet procurement application.Security and privacy are often the most critical directory features required of extranet applications because the application and its directory service may be accessible through the public Internet. Good performance and scalability of a directory product are also critical for large-scale extranet applications. Table 12.1. Directory product categories
Internet and Hosted ApplicationsThe business of an Internet service provider (ISP) is to provide Internet application access for end users and host applications on behalf of other organizations. ISPs typically provide services for very large numbers of users, and some ISPs provide hosting services for thousands of organizations. As Internet applications such as electronic mail increasingly depend on directory services, ISPs find themselves providing directory services too. Recently, more large organizations that do not consider themselves ISPs are finding that the most efficient way to streamline their own business processes is to act as a service provider for their divisions, departments, external partners , and suppliers. These enterprises that have many of the same needs as traditional ISPs have been dubbed enterprise service providers (ESPs). For ISP and ESP directory services to work well, they must meet a wide variety of application needs and be inexpensive to manage. Flexibility, scalability, performance, and automatable management are all very important in this segment of the market. Lightweight Database ApplicationsA relatively new role for LDAP directories is as a replacement for traditional database systems. The typical application being serviced is lightweight and query- intensive . Usually the data is widely distributed and actually shared by many applications. For example, a bank may need to share profile information about employees , customers, and partners among a wide variety of applications at thousands of distinct locations. High-performance, standards-based access to any kind of data can be achieved by placing the data in an LDAP directory and replicating it widely. Directory scalability (up to tens of millions of entries!), reliability, and write performance may all be very important for these kinds of applications. Table 12.1 provides a summary of these application categories and lists the typical needs that must be met by directory products. Just looking at the category that a specific directory product claims to address is no substitute for using the comprehensive evaluation criteria we help you create in the next section. However, it can help you quickly weed out products that are unlikely to meet your needs.
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Index terms contained in this sectionapplicationsdirectory software comparison table databases;lightweight;directory software ESPs (Enterprise Service Providers) extranet 2nd 3rd Internet and host 2nd intranet lightweight database network operating system choosing directory software 2nd comparison table ESPs (Enterprise Service providers extranet applications 2nd 3rd Internet and host applications 2nd intranet applications lightweight database applications 2nd network operating system applications databases lightweight directory software directories software 2nd comparison table ESPs (Enterprise Service Providers) extranet applications 2nd 3rd Internet and host applications 2nd intranet applications lightweight applications 2nd network operating system applications Enterprise Service Providers, see ESPs ESPs (Enterprise Service Providers) directory applications extranets directory software 2nd security and privacy hosts directory applications 2nd Internet directory software 2nd ESPs (Enterprise Service Providers) intranets directory software ISPs application software 2nd ESPs (Enterprise Service Providers) lightweight databases directory software 2nd networks extranets directory software 2nd 3rd Internet directory software 2nd 3rd intranets directory software operating system applications virtual extranets operating systems network applications privacy directory software privacy security directory software extranets software directory 2nd comparison table ESPs (Enterprise Service Providers extranet applications 2nd 3rd Internet and host applications 2nd intranet applications lightweight database applications 2nd network operating system applications tables directory software comparisons virtual networks extranets |
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