Microsoft .NET Server Solutions for the Enterprise

In this section we present a sample application that can be used to exchange data between business partners securely, reliably, and with non-repudiation. Also contained in this section are hardware and software requirements for the utility, installation procedures, and implementation configurations. The sample application, which we will name the Web Service File Transfer (WSTF) utility, is available on the companion CD-ROM, in the \Code\Web Service File Transfer folder. The information about installing and using the WSFT is given below.

The features of the WSFT sample application are:

• WSFT is based on industry standards. The WSFT uses industry standards for exchanging data. SOAP (Simple Object Access Protocol) is used with HTTP over the Secure Sockets Layer (HTTPS) to ensure secure and reliable data transfer through corporate firewalls.
• WSFT is built on Microsoft .NET. WSFT is built entirely with .NET technologies and uses the Web services of .NET.
• Data chunking. WSFT breaks large documents and files into smaller units (hence the term "chunking"). These smaller units of data are then transmitted over the Internet in parallel. At the destination, the segments are re-assembled in proper order to recreate the document or file.
• Data flow control. A receiving partner may not be able to receive data as fast as a sending partner can send it. WSFT allows the receiving partner to tell the sending partner what the maximum transfer rate should be. WSFT will then automatically adjust the data transmission rate to ensure the maximum rate is never exceeded. In addition, WSFT will automatically detect network congestion and slow the data transmission rate accordingly. When the congestion is cleared, it will automatically speed up data transmission again.
• Restart transmission. When transmitted over the Internet, the more the document s size increases, the greater the chance of an interruption in the transmission. WSFT has the ability to restart the transmission at the point where the interruption occurred, rather than starting from the beginning again.
• Secure transmission. WSFT can provide secure and reliable transmissions by requiring authentication and authorization. Authentication is enforced by the use of user identification and password, and a digital signature. WSFT also has the ability to determine user authorization. By supporting digital signatures, WSFT can also support document non-repudiation.

  Data confidentiality can be ensured by data encryption. Data encryption can be accomplished by using data keys between the two trading partners or by using the HTTPS protocol.

• Scalability. WSFT can support a varied system range from very small installations that use a single processor computer to very large installations that use clusters of multi-processors systems. WSFT is designed to receive message segments by different processes on different machines simultaneously.
• Performance. Initial tests have shown that WSFT is able to maintain a constant data transmission and receive rate regardless of the size of the document.