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IBM and the Internet

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1.5 IBM and the Internet

To the casual observer of a decade or so ago, it may have appeared that IBM had little interest in the Internet or TCP/IP. It is true that for a long period of time, certain parts of IBM involved in the development and marketing of SNA networks and protocols did consider TCP/IP to be a competitor. In fact, IBM has been practically involved in the development of the Internet for a long time, supplying software and hardware to NSFNET, for example. More importantly, IBM has long been involved in the various organizations, committees and task forces responsible for establishing open standards. IBM is currently represented on over 130 IETF Working Groups, helping to shape the future development of TCP/IP.

In March 1992, IBM introduced the Networking Blueprint (later expanded to become the Open Blueprint). The Open Blueprint is a framework, based on open and industry standards, for creating network solutions without concern for underlying networking components and services. It allows the incorporation of multiple

network protocols (including TCP/IP and SNA) into a single network. For details on the Open Blueprint, please refer to the Open Blueprint homepage at:

http://www.software.ibm.com/openblue

1.5.1 The Network Computing Framework

Today, Network Computing, the Internet and TCP/IP are at the core of IBM's strategy. IBM has developed a model for designing business solutions in the network computing environment - the Network Computing Framework for

e-business (NCF). NCF is based on an n-tier distributed environment where any number of tiers of application logic and business services are separated into components that communicate with each other across a network. In its most basic form, NCF can be depicted as a "logical" three-tier computing model, meaning that there is a logical, but not necessarily physical, separation of processes. This model is designed to support "thin clients" with high-function Web application and

enterprise servers.

A prototypical NCF three-tier architecture consists of:

1. A client tier containing logic related to the presentation of information (that is, the graphical user interface) and requests to applications through a browser or Java applet.

2. Web application servers containing the business logic and processes that control the reading and writing of data.

3. Servers that provide the data storage and transactional applications used by the Web application server processes.

The application elements residing in these three logical tiers are connected through a set of industry-standard protocols, services, and software connectors.

1.5.1.1 NCF Architecture

The NCF architecture provides a full range of services for developing and deploying e-business applications. Because it is based on industry standards, NCF has the ability to plug-and-play multiple components provided by any vendor. The NCF architecture is shown graphically in Figure 6.

Content Thin Clients

Tools

External Services e-business Application Services

Foundation Services Connectors

Systems Management Network Infrastructure Web Application Programming

Environment

Web Application Servers

3376E\3376F1DZ Figure 6. Network Computing Framework Architecture

The NCF architecture is composed of the following key elements:

Clients

NCF clients are "thin clients", meaning that little or no application logic is executed on the client and therefore relatively little software is required to be

installed on the client. In this model, applications are managed on the server and dynamically downloaded "on-demand" to requesting clients. As such, the client portions of new applications should be implemented in HTML, Dynamic HTML, XML, and Java applets. NCF supports a broad range of fixed, mobile, and "Tier 0" clients from IBM and other industry leaders, based on industry initiatives such as the Network Computer Profile, and the Mobile Network Computer Reference Specification.

Network infrastructure

The NCF network infrastructure provides a platform for the entire framework.

It includes the following services, all based on open standards:

Ÿ TCP/IP and network services, such as DHCP, that dynamically assign IP addresses as devices enter and leave the network.

Ÿ Security services based on public key technology that support user identification and authentication, access control, confidentiality, data integrity, and non-repudiation of transactions.

Ÿ Directory services that locate users, services, and resources in the network.

Ÿ Mobile services that provide access to valuable corporate data to the nomadic computing user.

Ÿ Client management services that support the setup, customization, and management of network computers, managed PCs, and in the future Tier 0 devices such as smartcards, digital cellphones, etc.

Ÿ File and print services that are accessed and managed via a standard Web browser interface.

Foundation Services

NCF foundation services provide the core functionality required to develop and support the business logic of e-business applications running on the Web application server. It includes the following services:

Ÿ An HTTP server that coordinates, collects, and assembles Web pages composed of static and dynamic content and delivers them to NCF clients.

Ÿ Mail and community services that provide e-mail messaging, calendaring and group scheduling, chat, and newsgroup discussions.

Ÿ Groupware services that provide a rich shared virtual workspace and support the coordination of business workflow processes.

Ÿ Database services that integrate the features and functions of an object-relational database with those of the Web application server.

Ÿ Transaction services that extend the Web application server by providing a highly available, robust, expandable and secure transactional

application execution environment.

Ÿ Messaging services that provide robust, asynchronous communication and message brokering facilities that support a publish/subscribe model of communication and message transformations.

Connectors

The bulk of today's critical data and application (especially transactional) programs reside on and use existing enterprise systems. NCF connectors allow existing data and application programs to work together with Web

clients and servers, seamlessly linking the strength of the Internet with the strength of the enterprise. At the core, connectors are software that provide linkage between the NCF Web server programming model environment and systems, applications, and services that are reached through the use of application specific protocols.

Web Application Programming Environment

The NCF Web application programming environment, based on Java servlets, Enterprise Java services and Enterprise JavaBean components, provides an environment for writing dynamic, transactional, secure business applications on Web application servers. Services are provided that promote separation of business and presentation logic enabling applications to dynamically adapt and tailor content based on user interests and client device.

e-business Application Services

NCF e-business application services are building blocks that facilitate the creation of e-business solutions. They are higher level application-oriented components that conform to the NCF programming model. They build on and extend the underlying NCF infrastructure and foundation services with

functions required for specific types of applications, for example, e-commerce applications. As a result, e-business solutions can be developed faster with higher quality. Examples of NCF e-business application services include payment services, catalog services, and order management services.

Systems Management

Within an enterprise, NCF systems management services provide the core functionality that supports end-to-end management across networks, systems, middleware and applications. NCF provides the tools and services that support management of the complete lifecycle of an application from installation and configuration, to the monitoring of its operational

characteristics such as availability and security, to the controlled update of changes. Across multiple enterprises, NCF provides a collaborative management approach for establishing and following procedures to share information and coordinate problem resolution with business partners. This collaborative approach includes policy management, data repository, scheduling and report generation.

Development Tools

NCF provides a broad range of tools to enable creation, deployment and management of e-business applications for Internet, extranet and intranet environments. It also supports integrating third-party tools into the development process. NCF supports the different skill sets involved in developing Web applications, providing tools that target specific skill sets, and facilitates collaboration among members of the development team.

1.5.1.2 API and Protocol Support

The following table summarizes the standard protocols and APIs supported by each component of the NCF architecture. While IBM will provide a complete and

competitive set of products that implement the framework, other implementations can also work within it. Thus, customers can choose from providers that support these open standards. Likewise, solution providers can build their solutions using a variety of software products sourced from different vendors.

Table 2. NCF - API and Protocol Support

Service Protocol Standard API

Network Infrastructure

Directory LDAP JNDI

Security CDSA, SSL, IPsec, x.509v3 certificates JSSL, JCE

Network TCP/IP JDK java.net

File AFS/DFS JDK java.io

Print IPP JDK java.2d, JNPAPI

Mobile MNCRP n/a

Foundation Services

Mail and Community SMTP, POP3, IMAP4, IRC, NNTP, FTP, iCalendar Java Notes API

Groupware n/a Java Notes API

Data ODBC, DRDA JDBC, JSQL, EJB

Transactions CORBA OTS/IIOP EJB, JTS

Message Queuing BMQS JMS

Web Application Programming Environment

Web Server HTTP, HTML, XML Servlets, Server-side-includes

Web Browser HTTP, HTML, XML Applets, DOM Level 1

Component Model CORBA IIOP JavaBeans

Business Component Model CORBA IIOP EJB, RMI

Scripting ECMAScript JSP (Java Server Pages)

Systems Management

Distribution (Install/Config) DMTF-CIM AMS

Operations (Fix/Change) DMTF-CIM AMS

Performance (Monitor) SNMP ARM

Events (Alarms) SNMP TEC

Development Tools

Authoring and Versioning WebDAV n/a

For a discussion of some of the protocols mentioned in Table 2 and IBM e-business solutions based upon them, please refer to Chapter 8, “Internet Protocols and Applications” on page 437.

For further details on NCF, please refer to the following IBM redbooks:

Ÿ SG24-5296 IBM Network Computing Framework for e-business Guide

Ÿ SG24-5220 Internet Security in the Network Computing Framework

Ÿ SG24-5205 Publishing Tools in the Network Computing Framework

Ÿ SG24-2119 Network Computing Framework Component Guide or refer to the Network Computing Framework home page at:

http://www.software.ibm.com/ebusiness

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