The Global Data Synchronization Network (GDSN) is a network of suppliers, retailers, and data pools that allows the exchange of item information globally via the Internet. It defines a common and modular set of attributes, a set of business messages, and a messaging choreography.
As a prerequisite you need a Global Location Number (GLN) and a Machine to Machine (M2M) connection to a GDSN data pool.
If, for example, you have an M2M connection with 1WorldSync, you may choose 1WorldSync Testpool as Connection Type: