Website Fundamentals PG#1

Active Server
Active Server Pages (ASP) technology is language-independent. Two of the most common scripting languages are supported right out of the box: VBScript and JScript. Support for other scripting languages, such as Perl, is available. Whatever scripting language you use, you can simply enclose script statements in special delimiters for ASP. The starting delimiter is <%, and the closing delimiter is %>.

VBScript: Using VBScript on the server in an ASP page isn't very different from using it in applications or on ordinary Web pages. Nearly all of the VBScript commands are available for use on the server. VBScript commands that interact with the user, however, are not available. For example, imagine a command that opens a dialog box on the server. No one is around to dismiss it, and the system can do nothing until someone dismisses it! The VBScript statements that present user interface elements are InputBox and MsgBox. In addition, the VBScript function CreateObject is replaced by a method of the Server object. This is necessary to track the object instances on the server side. You can add comments to your script just as you normally do. However, you cannot add comments inside an output expression. An output expression is an expression or value that is evaluated and written to the Web page. It is contained within the delimiters <%= and %>.

JScript: The rules for using JScript are very similar to those for VBScript. The delimiters are the same, for example. As with VBScript, you cannot use user interface statements such as the Alert statement. The way you use JScript on the server side is nearly identical to the way you use it on the client side. As on the client side, JScript on the server is case-sensitive. The rules for case in server-side scripts are:

The names of objects must be capitalized
Method and property names can be any case

You can also add support for other scripting languages, such as Perl, to IIS.

MS Internet Information Server
Internet Information Server Setup and Installation Features

Running a Web site is easy with Microsoft^®Windows NT^® Server and its built-in Web server, Internet Information Server (IIS). A new wizard gets you going quickly, and flexible administration tools let you manage the server any way you want to. IIS 4.0 provides the benefits of:

Integrated setup.
Flexible management.
Complete content control.
Configuration backup and restore.
Multiple web site hosting.
Network bandwidth allocation.
Familiar Windows NT Server administration tools.

Integrated setup
IIS 4.0 is installed as a component of the Microsoft Windows NT 4.0 Option Pack.

An integrated setup wizard makes it easy to setup and install the Web services and the various components that are part of the Windows NT 4.0 Option Pack. You simply check the items that you want to install, answer a few questions, and the installation wizard installs the desired configuration on the target machine.
When installing IIS 4.0 over the Internet, only the selected components are downloaded to your local machine. If you later decide to install other components, the installation program will automatically download the additional compressed component files and install them onto the machine.
You can automate the setup of IIS 4.0 to deploy it on many servers without remaining at the computer and stepping through the installation options. An unattended installation script can build a machine from scratch using Windows NT Server 4.0, the latest Service Pack, Internet Explorer 4.0, and selected components of the Window NT 4.0 Option Pack.

Flexible management
IIS 4.0 provides the most comprehensive set of tools for managing the Web server and its components. In addition to the rich management tools included with IIS 4.0, you can create your own custom interfaces using the IIS administration objects.

Windows-based administration
IIS 4.0 introduces the Microsoft Management Console (MMC), a Windows-based tool that enables the management of all Web services and applications from a single window.

Reduce administration time by learning a single interface.
Add Snap-in components to manage additional services and applications as your web site grows. IIS 4.0 includes snap-ins for WWW, FTP, SMTP, NNTP, Microsoft Transaction Server and Microsoft Index Server services.
The MMC lets you create custom consoles and delegate certain administration tasks while providing local and remote management capabilities for a single Web server or a farm of Web servers.

Web-based administration
An innovative Web-based administration tool designed using Active Server Pages and Jscript that can be viewed with any browser supporting scripting and frames.

Administrators can manage their Web servers remotely over the network using a standard Web browser.
Internet Service Providers (ISPs) who host many sites can provide their customers with this rich tool for managing their Web sites remotely from a Web browser.
The HTML Administration is built with Active Server Pages, so you can look at the ASP files to both understand how they were developed, and use them as a starting point for developing your own customized administration interface.

IIS Administration Objects
The IIS Administration Objects (IISAO) provide the ability to administer the entire server programmatically through a set of automation objects. Programmers can set all of the configuration parameters of IIS and to control its operation. The IISAO enable:

Command Line Administration - Administrators can automate common administration tasks by creating scripts and executing them from the command line or a Windows dialog.
Creation of Customized Administration Interfaces - Organizations can use the IISAO in an ASP or component to create a custom management interface to IIS. For example, the IISAO are used in the implementation of the Web-based administration program that ships with IIS 4.0. The IISAO can also be used in custom Visual Basic applications.

IIS 4.0 includes a set of sample scripts that automate common administrative tasks. This includes scripts to create, start, stop, pause and resume Web and ftp sites, create and remove virtual directories, control directory access settings, and utilities to display the configuration hierarchy, and search for specific configuration information.

Complete content control
IIS 4.0 provides complete flexibility and control over the property settings of the Web server and individual Web sites. You can now set properties on the Web server, Web site, virtual directory, and individual files. This flexibility gives you many performance and management benefits allowing you to:

Exclude all image files from being logged. This will increase performance, reduce the log file size and provide more accurate feedback on the number of page hits on your site.
Require SSL 3.0 security setting on a specific directory rather than an entire site. This will afford dramatic performance benefits while maintaining secure connections on appropriate pages.
Set properties at the server level and have them automatically apply to underlying directories and files on that server. This flexibility reduces the number of redundant management tasks because you will not have to set these properties individually.

Configuration backup and restore
IIS 4.0 provides a utility that saves configuration settings for all Web sites, FTP sites, virtual directories and files that are administered on the Web server.

Multiple backups include all the configuration settings and can be stored by name, version number, and date for future restoration.
To return to a previous configuration state and override the current configuration settings, an administrator simply selects one of the previously saved configurations and clicks restore.
Configuration files can be copied to other servers using the Content Replication Server, enabling a single staging server to be managed and replicated to an entire server farm.

Hosting multiple Web sites
Until recently, having multiple Web sites on a single server required each site to have a unique IP address. IIS 4.0 supports the HTTP 1.1 host header standard that allows individual Web sites on a single server to share a single IP address. Sharing an IP address makes management easier and enables IIS to support thousands of Web sites on a single server.

HTTP 1.1 is not yet supported by all browsers. IIS 4.0 provides support for these users by optionally displaying a list of all the Web sites on the server, and passing a cookie identifying the selected site.

Allocating network bandwidth
IIS 4.0 enables organizations running more than one site on the Web server to throttle, or allocate, bandwidth used by HTML files and graphics on each of the sites individually. Sites that receive high traffic can be allocated more network bandwidth than sites that receive less traffic. This eliminates the competition for bandwidth that can often delay or deny access on a busy network.

Familiar Windows NT Server administration tools
Administrators of Windows NT Server already have the basic knowledge to administer an IIS 4.0 server. Because IIS 4.0 is tightly integrated with Windows NT Server, it uses many of the existing management tools that a Windows NT Server administrator already knows and uses. These include:

User Manager for domains. Add a user to your system once and provide access to file, print, Web, and application services across all servers on your network. Single network logon means the user only has to sign-in once to access all the services.
Performance monitor. Performance Monitor is a powerful tool for monitoring the performance of any Windows NT Server on the network. IIS 4.0 includes counters for its HTTP and indexing services to monitor the performance and load on the server.
Event Viewer. Event Viewer is the tool you use to monitor various systems events on Windows NT Server. IIS takes full advantage of the Event Viewer to log application and security events pertaining to the Web server. Administrators can use Event Viewer as a second log to audit access to secure files.

WebClasses
WebClasses™ allows complete management of your training classes without leaving your browser! WebClasses™ can save hundreds of phone calls to your training center and can operate 24 hours a day, 7 days a week! Enrollment screens allow students to check course lists, search through courses, and enroll on-line.

An easy-to-use administration screen allows your training center to add, remove and modify classes and to modify class registration. A new feature of WebClasses™ allows students to fill out course evaluations on-line! No more paper handouts that are misplaced and never filled out. Course administrators can view the results on-line, or use a special "export" feature to download evaluation results for importing into Microsoft Excel or any database program.

Combined with WebSchedule™ to manage classroom and resource reservation, you can manage your entire training center through your browser!

JavaScript & Java
JavaScript: JavaScript is a compact, object-based scripting language for developing client and server Internet applications. Netscape Navigator interprets JavaScript statements embedded in an HTML page, and LiveWire enables you to create server-based applications similar to Common Gateway Interface (CGI) programs.

Java: Java, formerly known as oak, is an object-oriented programming language developed by Sun. It shares many superficial similarities with C, C++, and Objective C (for instance for loops have the same syntax in all four languages); but it is not based on any of those languages, nor have efforts been made to make it compatible with them. Java is sometimes referred to as C++ ++ --. The language was originally created because C++ proved inadequate for certain tasks. Since the designers were not burdened with compatibility with existing languages, they were able to learn from the experience and mistakes of previous object-oriented languages. They added a few things C++ doesn't have like garbage collection and multithreading; and they threw away C++ features that had proven to be better in theory than in practice like multiple inheritance and operator overloading. Even more importantly Java was designed from the ground up to allow for secure execution of code across a network, even when the source of that code was untrusted and possibly malicious. This required the elimination of more features of C and C++. Most notably there are no pointers in Java. Java programs cannot (at least in theory) access arbitrary addresses in memory. Furthermore Java was designed not only to be cross-platform in source form like C, but also in compiled binary form. Since this is frankly impossible across processor architectures, Java is compiled to an intermediate byte-code which is interpreted on the fly by the Java interpreter. Thus to port Java programs to a new platform all that is needed is a port of the interpreter and a few native code libraries. Finally Java was designed to make it a lot easier to write bug free code. Shipping C code has, on average, one bug per 55 lines of code. About half of these bugs are related to memory allocation and deallocation. Thus Java has a number of features to make bugs less common:

Strong Typing
No unsafe constructs
The language is small so its easy to become fluent.
The language is easy to read and write. Obfuscated Java isn't nearly as common as obfuscated C.
There are no undefined or architecture dependent constructs.
Java is object oriented so reuse is easy.
Java has concurrency.

Client Server
What is the difference between Client and Server?

A client is somebody who makes a request, or asks somebody for something.

A server is somebody who answers the request, or "serves".

What the three major types of software that every server must have:

An operating system


Your operating system is the software layer that directly manages your hardware and allows

your programs to function on that hardware.

TCP/IP software pacakage Trasmission Control Protocol/Internet Protocol
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The server must communicate using a protocol suite called TCP/IP, which is the stanard

format of data transmission on the Internet. This is loaded by default on Win NT 4. This is how

it is possible for various types of dissimilar computers to exchange information. Every server

converts its information to TCP/IP packets and then sends them out to the world. The computer

receiving this information then converts it to something it understands before processing the

actual data.
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TCP/IP suite supports these well-known Internet services:
1. FTP File Transfer Protocol allows the user of one computer to connect to another computer for the purpose of transferring files. While connected the user can exchange files as well as navigate around the other computer's file system
2. SMTP Simple Mail Transfer Protocol provides the mechanism for sending mail between systems.
3. NNTP Netwrok News Transport Protocol works only with Usenet news articles.
4. Telnet allows you to become a user on a remote computer. Once connected, your computer becomes a terminal directly connected to the other computer.
5. NFS the protocol for network file systems allows one computer to connect to another computer and make the files on the other computer available to users of the first computer. It is similar concept to a file server.
HTTPd the "d" stands for daemon (a system programs those runs in the background and automatically handles certain system operations.) The Web's communication mechanism.