The Global Location Number (GLN) is a structured Identification of a physical location, legal or functional entity within an enterprise. The GLN is the primary party identifier. Each party identified in the trading relationship must have a primary party Identification.
Message-specific definition:
A data pool that supports the functionality required by a Data Source such as Data Loading, Publication, Notification, Registration, etc.
External references:
More information about the Global Location Numbers can be found here: http://www.gs1.org/productssolutions/barcodes/technical/idkeys/gln.html