Microsoft® SQL Server™ Net-Library architecture for client/server applications is based on the Net-Library concept that abstracts the client and server applications from the underlying network protocols being used.
Tabular Data Stream (TDS) is the data stream protocol used by SQL Server to transfer requests and responses between the client and the server. TDS is a logical data stream protocol and must be supported by a physical network interprocess communication mechanism (IPC). The Net-Library architecture provides a method of sending TDS across a physical network connection, and it provides a transparent interface to DB-Library for C.