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ASP 3.0 is the latest version of ASP, but there will never be an ASP 4.0 version. ASP.NET is the next generation ASP, but it's not an upgraded version of ASP. ASP.NET is an entirely new paradigm for server-side ASP scripting.

ASP.NET is a part of the .NET Framework. Microsoft spent three years rewriting ASP.NET from the ground up, and ASP.NET is not fully backward compatible with ASP 3.0.

.NET Framework

The .NET Framework is the infrastructure for the Microsoft .NET platform.

The .NET Framework is an environment for building, deploying, and running Web applications and Web Services.

The .NET Framework contains a common language runtime and common class libraries - like ADO.NET, ASP.NET and Windows Forms - to provide advanced standard services that can be integrated into a variety of computer systems.

The .NET Framework provides a feature-rich application environment, simplified development and easy integration between a numbers of different development languages.

Microsoft's Visual Studio.NET is a common development environment for the .NET Framework.

New in ASP .NET

 Better language support  Programmable controls  Event-driven programming  XML-based components

 User authentication, with accounts and roles  Higher scalability

 Increased performance - Compiled code  Easier configuration and deployment  Not fully ASP compatible

Microsoft Introduces C#

C# is Microsoft's new programming language for the .NET platform. It combines some of the best features of modern programming languages such as Java, C++ or Visual Basic. C# is an object-oriented language with single inheritance but multiple interfaces per class. It supports component-based programming by properties (smart fields), events and delegates (enhanced function pointers). C# is fully interoperable with other .NET languages such as VB.NET, Eiffel.NET or Oberon.NET.

C# is designed to be a platform-independent language in the tradition of Java. It's syntax is similar to C and C++ syntax, and C# is designed to be an object-oriented language. There are, for the most part, minor variations in syntax between C++ and C#. Main has no return type, there are no semicolons after class names, there are some (to C++ programmers) strange decisions regarding capitalization - such as the capitalization of Main. Other a few differences, the syntax is often the same. This decision is reasonable, in light of the fact that C syntax has been used with several other languages - notably Java.

the class is guaranteed to implement. Interfaces avoid the messy dangers of multiple inheritance while maintaining the ability to let several classes implement the same set of methods.

Another helpful feature of C# is garbage collection. Therefore, it is unnecessary to include a destructor for each class unless a class handles unmanaged resources; if so, it's necessary to release control those resources from within the class (The Finalize function is used to clear up these unmanaged resources; it can even be abbreviated with the same syntax as a C++ destructor). Of course, C# also provides direct access to memory through C++ style pointers, but these pointers are not garbage collected until specifically released by the programmer.

C#, as part of the .NET framework, is compiled to Microsoft Intermediate Language (MSIL), which is a language similar to Java's byte code. MSIL allows C# to be platform independent and runs using just in time compiling. Therefore programs running under .NET gain speed with repeated use.

Furthermore, because the other languages that make up the .NET platform (including VB and COBOL) compile to MSIL, it is possible for classes to be inherited across languages. The MSIL, like byte code, is what allows C# to be platform independent.

C# Advantages:

• XML documentation generated from source code comments. (This is coming in VB.NET with Whidbey (the code name for the next version of Visual Studio and .NET), and there are tools which will do it with existing VB.NET code already.)

• Operator overloading - again, coming to VB.NET in Whidbey.

• Language support for unsigned types (you can use them from VB.NET, but they aren't in the language itself). Again, support for these is coming to VB.NET in Whidbey.

• Explicit interface implementation, where an interface which is already implemented in a base class can be reimplemented separately in a derived class. Arguably this makes the class harder to understand, in the same way that member hiding normally does.

• Unsafe code. This allows pointer arithmetic etc, and can improve performance in some situations. However, it is not to be used lightly, as a lot of the normal safety of C# is lost (as the name implies). Note that unsafe code is still

managed code, i.e. it is compiled to IL, JITted, and run within the CLR.

Conclusion:

C# is a modern, object-oriented language that enables programmers to quickly and easily build solutions for the Microsoft .NET platform. The framework provided allows C# components to become XML Web services that are available across the Internet, from any application running on any platform.

The language enhances developer productivity while serving to eliminate programming errors that can lead to increased development costs. C# brings rapid Web development to the C and C++ programmer while maintaining the power and flexibility that those developers call for.

SQL Server 2000

SQL Server 2000 only works on Windows-based platforms, including Windows 9x, Windows NT, Windows 2000 and Windows CE.

In the case of SQL Server, authentication is handled by comparing credentials provided by a connecting user with set of entries stored in the sysxlogin table of the SQL server master database (to get familiar with its content, you might want to use sysloging view, presenting data in a more friendly format). The way these credentials

are provided depends on the authentication mode, which can be set to one of the following:

•

SQL Server authentication: in this case, SQL Server requires that a user

specifies a name and password at the time when connection is attempted. The login name and one-way hash of the password need to match one of entries in the sysxlogin table for the login attempt to be successful.

•

Windows authentication: in this case, SQL Server does not prompt a

user for credentials, but instead it uses an access token assigned at the time the user logged on using a Windows account. This can be a token generated by the Windows operating system on which SQL Server was installed (in case of a local user account) or by a Windows NT 4.0 or Active Directory domain, (if a user domain account is used). The token contains a security identifier (SID) which uniquely identifies the user, as well as SIDs of local (or domain) groups that the user is a member of. SQL compares all of the SIDs stored in the token against entries in the sysxlogin table and, depending on the outcome; it grants or denies login privileges. Presence of a matching entry is not sufficient though for logon to be allowed, since with Windows authentication, it is possible to not only grant login privileges to a specific SID but also deny them (denying rights will always take precedence over granting them). This means that you can, for example, grant login privileges to a Windows group, but still deny access to SQL server to some of its members.

SQL Server creates two default logins (entries in the sysxlogin table) at the installation time, granted the highest possible level of administrative privileges. The first one is the SA login, allowing access using SQL Server authentication, the second is the BUILTIN Administrators, representing SID of the local Administrators Windows group on the SQL Server computer and allowing every member of this group to access the server via Windows authentication.