GDSN vs EDI: what's the difference?

What is GDSN?

GDSN stands for Global Data Synchronization Network. It's an internet-based, interconnected network of interoperable data pools governed by GS1 standards that lets manufacturers and retailers keep one shared, accurate version of a product's master data instead of chasing spreadsheets between them.

Practically, the GDSN is an internet-based, interconnected network of interoperable data pools governed by GS1 standards that enables companies around the globe to exchange standardized product master data with their trading partners. The mechanism behind it is publish-subscribe, not file transfer. The GDSN operates using a publish-subscribe pattern between two trading partners, each of which are registered with and access the GDSN via a data pool, and the GS1 Global Registry acts as a directory to point to the data pool where data is housed, matching subscription to registrations.

Notice what's missing from that description: purchase orders, invoices, shipment notices. That's the point. GDSN syncs dimensions, GTINs, images, and packaging hierarchy. It never carries a transaction.

GDSN vs EDI: what's actually different

The short answer to GDSN vs EDI: EDI moves transactions (POs, invoices, ASNs) between two specific parties for a specific event, while GDSN moves static master data records that those transactions later reference. One is about "what happened," the other is about "what this item is."

EDI's whole architecture is built around the transaction set. One or more data segments framed by a header and trailer form a transaction set, which is the EDI unit of transmission, equivalent to a message, and often consists of what is usually contained in a typical business document or form. An X12 850 or an EDIFACT ORDERS message exists because a business event occurred: someone placed an order. GDSN has no equivalent event trigger. A GTIN's case pack dimensions don't change because a truck left a dock; they change because someone updated the item record and republished it.

GS1's own account of how data exchange evolved makes the relationship clear: it moved through unstructured messaging, then national EDI such as Tradacom, then global EDI through EANCOM, before arriving at the Global Data Synchronisation Network built on GDSN-certified data pools. GDSN didn't replace EDI in that timeline. It was layered on top, as a separate network solving a separate problem: keeping master data consistent before the transactions that depend on it ever fire.

The building blocks: GLN, GTIN, and data pools

Two identifiers make GDSN and EDI interoperate at all. The Global Location Number (GLN) and the Global Trade Item Number (GTIN) are the global identification numbers in the GDSN, with the GLN identifying legal entities, trading partners and locations, and the GTIN identifying trade items. Once a GTIN exists in GDSN, that same number shows up inside your EDI documents. Once a GLN identifies a distribution center, that same number shows up as a ship-to qualifier in an 856 ASN.

You don't connect to "GDSN" directly. You subscribe to a certified data pool, and there are currently 44 GDSN-certified data pools, all offering GDSN storage and synchronization but differing by additional information managed, supportive services, and pricing models. 1WorldSync and Syndigo are the two names you'll hear most often in retail and grocery onboarding conversations, but Commport and dozens of regional providers run certified pools too.

Worked example: onboarding a supplier to Walmart

Here's how the two systems actually stack, using the retailer most EDI teams have dealt with directly. Walmart has partnered with 1WorldSync to implement Global Data Synchronization, so a new supplier's first move is registering the item there, not in an EDI test environment.

1. The supplier publishes a new SKU into 1WorldSync: GTIN, case pack, dimensions, weight, images.
2. Walmart's systems, subscribed via the GS1 Global Registry, pull that item record automatically once the publish/subscribe match fires.
3. Only once the item exists in Walmart's system does the commercial relationship start over EDI: an 850 purchase order references the GTIN, an 856 ASN carries the GLN for ship-to, and an 810 invoice ties back to the same identifiers.

Skip step one and step three breaks immediately. Buyers can't cut a PO against a GTIN their system has never seen.

One thing worth knowing before you assume GDSN is mandatory everywhere: it isn't universal. Walmart stopped requiring GDSN capabilities from brands, and Amazon, W. W. Grainger, and The Home Depot have never required them. Some retailers and grocers still mandate a specific certified pool as a condition of doing business. Others will accept item data through a portal or a spreadsheet upload instead. Check the specific retailer's onboarding packet before you assume you need a data pool subscription at all.

Where this connects to transport and carrier data

The same GLNs that identify a ship-to location in GDSN reappear downstream in transport execution. Once an item and its locations exist as clean master data, that same GLN feeds the ship-from/ship-to fields in an 856 ASN or an IFTMIN transport instruction, and gets consumed by TMS and carrier-connectivity platforms when a load actually gets tendered and tracked. Systems like MercuryGate, Descartes, Blue Yonder, Oracle Transportation Management, and lighter-weight platforms such as Cargoson don't create these identifiers, they consume them, using the location and item data that GDSN and EDI already established to execute the physical shipment.

Common mistakes teams make

• Treating GDSN certification as a substitute for EDI capability. Retailers that require GDSN almost always still require full EDI compliance for the transactional side.
• Letting master data go stale after go-live. GDSN isn't set-and-forget: a GTIN attribute change has to be republished, or your 850s and 856s keep referencing outdated case dimensions and weights.
• Assuming one data pool subscription covers every retailer. Because only 33 percent of data pools work together, suppliers must decipher and use the ones that do, so a pool that syncs cleanly with one buying organization may not sync with another at all.

FAQ

Is GDSN a type of EDI?
No. They're governed by different standard bodies (GS1 versus X12/EDIFACT), move different content (master data versus transactions), and typically run through entirely separate systems, even though many companies need both.

Do I need GDSN if I already do EDI with a retailer?
Depends on the mandate. Some grocery and CPG retailers require both a GDSN subscription and full EDI compliance. Others, as the Walmart and Amazon examples above show, never required GDSN at all. Check the trading partner's onboarding guide, not a general assumption.

What's the difference between GDSN and a PIM system?
PIM (Product Information Management) is a centralized system for managing product data across various channels, ensuring consistency and accuracy in product information, and it focuses on internal management and distribution of product data across multiple platforms, while GDSN is the external network used to publish that data to trading partners. Most large suppliers run PIM internally and feed a GDSN data pool from it.

Who certifies GDSN data pools?
Drummond Group, LLC is GS1's official GDSN testing and certification agency. Any data pool provider you're evaluating should be able to point to that certification directly.