What is DEX?

DEX, Direct Exchange, is a form of electronic data interchange, EDI, used by direct store delivery, DSD, distributors to electronically send their delivery information, invoices and or credit memos, to the retailer at the time of delivery.  DEX has been around for many years and is used by all major grocery retailers as well as numerous smaller chains and convenience stores.

Benefits of DEX

DEX allows the retailer to electronically receive the invoice from the distributor at the time the product is delivered.  This eliminates the cost of manual data entry as well as the elimination of data input errors.  Additionally the electronic importing means the data is in the system at the time of delivery which is important to keep inventory accurate.  It also eliminates invoice processing times which may impact terms of payment regulations.  DEX also allows for the checking of quantities, prices and authorized products.  This will guarantee that what is on the invoice is what is received at the correct cost as well as eliminating unknown product getting to checkout.  The majority of the benefits of DEX are on the retailer’s side.  Retailers can encourage distributors to DEX by offering incentives such as giving receiving priority to those with DEX capable handhelds.  If there is a waiting line to be checked in, those distributors who can DEX move ahead of those who can not.

The DEX Process

Most DSD distributors have a handheld computer that is used to create or edit invoices at the time of delivery.  The DSD distributor creates the invoice at the retailer once they see how much product is remaining on the shelf.  This method of delivery allows the sales rep to get a more accurate count of what needs to be delivered.  Once the sales rep is finished creating the invoice on the handheld, if the sales rep’s handheld is DEX capable, it can be connected to the retailers computer and the invoice can be electronically sent across.  DEX allows for the electronic exchange of the delivery information to happen at the time of the delivery since that information is not known prior to delivery.  The DEX standard was developed so that any DSD distributor can electronically send an invoice to any retailer that supports DEX.  The DEX standard specifies the type of connection between the distributors handheld computer and the retailer, the format of the data files, the file transfer method used by both trading partners and the process.

Technical Details of DEX

At its most basic, DEX is an exchange of data between 2 computers over a serial cable.  The initial file sent from the distributor is known as an 894 record set and typically contains 1 or more invoices and or credit memos.  The retailer then creates a file called an 895 that may contain either adjustments to the data in the distributors 894 or an acknowledgment that the data in the 894 was accepted.  Once one side or the other has sent an 895 acknowledgment, the process is finished.  The physical method for exchanging the data is through a serial cable in which the distributor has a ¼ inch male stereo jack connection and the retailer provides a ¼ inch female stereo jack connection.  The computers use the ANSI X3.28 transfer protocol to send across the 894 and 895 data files.

Implementing DEX

For the retailer, implementation requires DEX receiving software that is integrated with the back end accounting system and one or more of the ¼ inch female stereo jack connections located in a place available to the sales rep.  The level of integration for the retailer can vary depending on a number of factors such as receiving staff availability.  For example most large retailers receive the 894 and a receiving clerk compares the product and quantities on the invoice with the product being brought into the store.  As part of this process, the stores computer will typically check that the products are authorized and that the cost for the product the retailer has on file matches the cost on the invoice.  If all is correct, an 895 acknowledgment is created for the distributor to receive.  If there were discrepancies, the retailer would create an 895 adjustment.  Once a vendor receives an adjustment, in most cases the vendor would then send back an 895 acknowledgment to end the DEX process.  If the retailer does not have a dedicated receiving person, which is typical in smaller retailers such as convenience stores, the retailer may setup DEX to automatically create an 895 acknowledgment file when an 894 is received.  This still allows the retailer to import in the data from the 894 without manual data entry costs or errors.  

Working With Vendors

The first step in working with vendors is to exchange DEX related information.  Both sides need to exchange a Communication ID, DUNS number and the DEX version to use.  The Communication ID is a 10 digit code supplied to both the retailer and the vendor by GS1.  The DUNS number is a 9 digit code supplied by Dun and Bradstreet.  Over the years the DEX standard has been modified and with each modification the version number is updated.  Most retailers and vendors can support multiple versions.  It is important that both trading partners are able to support a common version of the DEX standard. In most cases the retailer will specify the preferred version and potentially alternate versions they support.

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