Introduction

Winsock control comes with VB6 and is used to create applications that access the low-level functions of the Transmission Control Protocol/Internet Protocol (TCP/IP).

Most of you might have worked with Internet Transfer Control which is very handy control when it comes to Internet Programming but there is another control which even more robust and helps programmers creating more flexible applications. Winsock control comes with VB6 and is used to create applications that access the low-level functions of the Transmission Control Protocol/Internet Protocol (TCP/IP).

TCP/IP is a specification that defines a series of protocols used to standardize how computers exchange information with each other. TCP/IP provides communication across interconnected networks that use diverse hardware architectures and various operating systems. The protocols in TCP/IP are arranged in a series of layers known as a protocol stack. Each layer has its own functionality.

Winsock is a standard that is maintained by Microsoft. This standard is basically a set of routines that describe communications to and from the TCP/IP stack. These routines reside in a dynamic link library that runs under Windows. The winsock DLL is interfaced with TCP/IP and from there through the Internet.

In this article, I am going to show how to use the winsock in a client server environment, we will create two separate applications, one of which will be a server and the other will be a client. Both client and server will interact with each other to exchange data. Client will send a request to the server and the server which will be connected to a database will retrieve the information requested by the client from the database and will return the requested information back to the client. You will a database with this article, the database contains the item numbers and their prices. In real life situations, database might be located on a machine different from the one that hosts the client application.