A. INTRANET BASICS

A1. Intranet defined

In' tra net - n. 1) a network connecting an affiliated set of clients using standard internet protocols, esp. TCP/IP and HTTP. 2) an IP-based network of nodes behind a firewall, or behind several firewalls connected by secure, possibly virtual, networks.

A2. What is an "internal web"? A corporate web?

In general, a web is an unstructured client/server network that uses HTTP as its transaction protocol. The World Wide Web comprises all HTTP nodes on the public Internet. An internal web comprises all HTTP nodes on a private network, such as an organization's LAN or WAN. If the organization is a corporation, the internal web is also a corporate web.

If a corporate web connects two or more trading partners, it is often referred to as a business-to-business web, or an extranet.

Note that internal webs - also known as intranets - are only logically "internal" to an organization. Physically they can span the globe, as long as access is limited to a defined community of interest.

Nomenclature: Throughout Intranet Design Magazine® the convention is used that the first letter of the word "Web" is capitalized only when referring to the World Wide Web. Webs on private networks are referred to as "webs," with a lowercase "w".

A3. How big can an intranet be?

As a big as a community of interest. Scale is an important factor in web implementation, but it has no bearing on the logical association of clients that make up an intranet. For example, a workgroup with one web server, a company with several hundred web servers, and a professional organization with ten thousand web servers can each be considered an intranet.

While nothing constrains these webs to be "inside" or bounded in any physical sense, size is a significant from a network design perspective. Intranet Design Magazine® refers to expansive private webs wide-area intranets or extranets to connote that WAN economics and technologies apply.

A4. How do intranets relate to groupware?

Groupware, a term coined by marketeers around 1995 to mean "software that facilitiates group work," never emerged as a well-defined software category. Today the term is used less and tends to be narrowly identified with three products: Lotus Notes, Microsoft Exchange and Novell GroupWise.

Groupware functionality is roughly synonomous with collaborative computing and embraces the following:

• document sharing
• collaborative authoring
• versioning
• messaging
• secure access
• search/retrieval
• discussion forums
• database integration.

Intranet technology is well-suited to many of these tasks, having matured in areas where it was initially weak, such as security and integrated search. The major groupware products have shifted from their early proprietary roots to internet-based architectures. For instance, Microsoft Exchange 5.5 supports POP3 and IMAP4 Internet mail, NNTP-based newsgroups, and LDAP directory services.

Perspectives. For an early, lucid explanation of groupware, see Lotus' seminal white paper, "Groupware -- Communication, Collaboration, Coordination" (1995). Lotus has since recast Notes as a type of Knowledge Management (KM) software, as has Lotus-competitor Open Text Corporation regarding its flagship product Livelink Intranet. IDM maintains a listing of additional products in the KM / Content Management / Portal space, which some consider the successor to groupware.

For a vendor-neutral discussion of web-based collaboration see NCSA's Habanero project, an investigation of "the enhancements in distributed interpersonal communication made possible when single-user computer software tools are recast as multi-user, collaborative work environments."

Resources. Intranets as Groupware (John Wiley & Sons, Nov 1996) by Mellanie Hills.

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A5. How do intranets relate to e-mail?

It's a marriage made in CyberHeaven. E-mail is networking's killer app and the foundation of Internet messaging. Intranets inherit Simple Mail Transport Protocol (SMTP, RFC-822) from the TCP/IP suite. On top of SMTP, which enables plain text messaging, intranets use Multipurpose Internet Mail Extensions (MIME, RFC-2045) to carry diverse content. In fact, the MIME content types are the Web's content types -- adding a new format such as streaming audio amounts to defining a new MIME type.

Because intranets have established Internet mail as the de facto messaging standard, they are replacing proprietary mail systems such as Lotus VIM and Microsoft MAPI in much the same way they have other proprietary network protocols.

Resources. Internet Messaging: From the Desktop to the Enterprise (Prentice-Hall, July 1998) by David Strom and Marshall T. Rose.

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A6. Are intranets compatible with my Novell network?

Yes. If your enterprise LAN is based on Netware, you have several options besides running a separate TCP/IP environment. One is Novell's own IntranetWare. Nicely integrated, IntranetWare authenticates users against Novell Directory Services (NDS), simplifying security administration. Standard NCSA-style web security is also supported. SMTP gateways are available from Novell and other vendors to enable the Web Server to process "mailto:" requests.

Unfortunately for Novell, NetWare has never been a particularly open environment, and the lack of a third-party application market has limited adoption of NetWare for new web projects. Recognizing this, Novell formed in 1997 a joint subsidiary called Novonyx, Inc. with Netscape Communications Corp. to co-develop a NetWare port of Netscape SuiteSpot. Novonyx was rolled back into Novell in early 1998.

More recently Novell has recast its application hosting strategy in terms of Java, and is emphasizing the demonstrated virtues of its security and directory services. For example, Novell hosted an impressive demonstration of the NDS [Novell Directory Server] at Fall Comdex 1997, managing a 250,000-node intranet.

For a good summary of Novell's platform vis á vis Unix and NT, see "NetWare 5: An Elegant Interoperability Solution," by Aberdeen Group, a Boston-based market research firm.

A7. We run IPX. Is TCP/IP required to create an intranet?

Yes and no. Yes, TCP/IP is required on the web server, since HTTP is a TCP/IP service. At the client, where concern about protocol explosion is greatest, you don't actually need an IP stack. Gateway products that run IP packets over IPX enable NetWare shops to build an intranet without complex additions to each desktop.

One such product is NOV*IX for NetWare from FTP Software, Inc. (Andover, MA). NOV*IX bundles a unique Winsock which preserves the application-side TCP/IP interface but speaks IPX/SPX over the network. Client IP packets are unwrapped at the server and distributed across the intranet in native form. The destination server might be a Novell WebServer, a Unix platform running HTTP, or another Novell file server running NOV*IX. The server processes the client request and returns the result via TCP/IP. Finally, to reach the originating client, result packets are encapsulated in IPX and returned using NetWare protocols. The NOV*IX Winsock passes the response to the client application layer.

On the downside, packet translation is processor intensive, and may require hardware upgrades to maintain performance. With even mainframes trafficking in TCP/IP these days, you should consider any non-IP arrangement as a stepping stone rather than a long-term solution.

A8. How do intranets relate to client/server systems?

Intranets follow a multi-tier application architecture with roughly the following correspondences:

Browser = Client.
Web server and Application servers = Business logic tiers.
CGI, proprietary server API, JDBC driver or Message Queueing = Middleware.
Component Transaction Server = Transaction Manager
Database servers = Back-end data stores.

A9. How do webs relate to object/component technology?

There are several theoretical answers to this question, all of which are still evolving and represented by aggressively marketed products. The following references should give you the insight to form your own opinions.

For more detail on distributed object computing and the Web, see "Objects and the Web" in this FAQ.

On the theory side, see the W3 Project's object-web initiative, which discusses CORBA integration and O-O applet technologies. The W3Objects Group of the Arjuna project at Newcastle University, UK, makes available some illuminating papers on O-O and the Web. ANSA, a complementary project, hosts a well-illustrated paper called A Web of Distributed Objects.

Practically speaking, today's web-object strategies fall into two camps: Microsoft DNA [Distributed interNet Architecture] and CORBA / IIOP [Internet Inter-ORB Protocol]. Earlier contenders, such as the IBM-HP-Apple alliance Taligent, have been assimilated into more marketable vehicles such as IBM's Java agenda.

Microsoft DNA.
Microsoft pitches its current approach to intranets, sketched at right, in a dedicated section of its web site. Interestingly (some might say perversely), Microsoft has never acknowledged industry-standard norms of object technology, couching its products instead in terms of a component architecture originally called OLE (pronounced o-lay'), later COM. This began with Visual Basic Controls (VBX's), the building blocks of 16-bit VB applications. VBXs graduated to 32-bit OCX's. Neither of these early technologies was networkable.

From 1995, with the rise of business internetnetworking, Microsoft recast OCX visual controls as Internet-aware ActiveX controls. At the same time, the company began expanding its Component Object Model (COM) to embrace many of the strategic features of CORBA, including transaction management, message queueing and language independence.

In late 1997 Microsoft introduced an umbrella architecture, DNA, to rationalize its growing number of Internet-related brands. DNA includes COM, Distributed COM (DCOM), Internet Information Server (IIS), Active Server Pages (ASP), Active Data Objects (ADO) and OLE DB, Microsoft Transaction Services (MTS), MSMQ, and other related brands.

One of the chief differences between DNA and CORBA is that DNA technology is optimized for Windows NT, where CORBA is designed to be platform neutral.

CORBA. Common Object Request Broker Architecture (CORBA) is an industry-wide standards initiative organized by the Object Management Group (OMG) to provide a platform neutral infrastructure for mission-critical distributed applications. Good summaries can be found on the OMG home page, in the official CORBA FAQ, and on the web site, "Distributed Object Computing with CORBA Middleware" maintained by Douglas C. Schmidt.

CORBA aims to be implementation-neutral. IBM and Sun Microsystems have thrown their considerable weight behind IIOP, a lightweight standard for object brokering on TCP/IP networks. IIOP improves on HTTP as a lingua franca for web communication, and is considered by some (though by no means all) a candidate to replace it. You can get a sense of industry interest in CORBA/IIOP from OMG's list of committed vendors.

Java^TM continues to be a hot prospect for implementing distributed objects, via a technique called Remote Method Invocation. Compare this to "Java - The Microsoft Perspective," by Roger Sessions.