What is EDI ?

EDI stands for Electronic Data Interchange

To understand the need for EDI, lets take a business flow and transactions involved. Company "C" is a manufacturer and regularly buys raw material from Supplier "S" that would typically involve below transactions for each purchase done. 

1. Buyer at Customer "C" enters a Purchase Order in his computer system
2. Buyer sends the PO through email or fax or mail to Supplier "S"
3. Sales team at Supplier "S" validates the PO to ensure that required information is provided
4. Sales team at Supplier "S" enters a Sales Order in his computer system
5. Sales team at Supplier "S" sends the Sales Order acknowledgment to Customer "C" through email or fax or regular mail

Imagine the cost, cycle time, money and risks of data entry errors involved in the above process. What if computer system at Customer "C" exchanges data with computer system at Supplier "S" using an intermediate communication link ? Yes, that's the idea behind EDI.

Organizations that send or receive documents between each other are referred to as "trading partners" in EDI terminology. Trading partners are free to use any method for the transmission of documents. Few of the transmission mediums used are Value Added Network (VAN), Internet/AS and Web EDI.

EDI translation software, popularly known as Translator, validates the partner and checks if the data received meets the standard formats defined before converting it to a desired file format which can be read and imported by the receiver's computer systems (for e.g. ERP)

EDIFACT & X12 are most widely followed EDI standards. The standards prescribe the formats, character sets, and data elements used in the exchange of business documents and forms. 

Oracle e-Commerce gateway (earlier EDI gateway) module helps organizations meet their EDI requirements with flexibility to use choice of your translator, EDI standard and yet tightly integrates with other modules from Oracle.

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Oracle eCommerce Gateway Overview

The Oracle Gateway resides between the Oracle Applications and the EDI Translator. The Gateway processes data between Oracle Applications and the EDI Translator using ASCII interface flat files. The EDI Translator accommodates the standards and all the monitoring of transmitting standard formatted data between Trading Partners. For outbound data, the EDI Translator maps data from the Oracle interface flat files to any standards of choice. For inbound data, the EDI Translator maps data from the standards of choice to the Oracle interface flat file. The format and content of this flat file can be easily adjusted using the open interface definition table within the Oracle Gateway, though any changes that are made should also be implemented within the EDI Translator set-up. The Gateway processes data via an interface file which is received from or sent to the EDI Translator. The Gateway is independent of all standard formats since only the business data is found in the Oracle Gateway defined interface files. Additionally, the Oracle Gateway provides general code conversion functions for data such as Unit of Measure, Shipping Codes, Payment Terms, and determines the Trading Partner EDI validation/authorization between the Oracle application and the EDI Translator. Inbound Transactions For inbound transactions Oracle Gateway populates the Application Open Interfaces within the Oracle Application products. All of the necessary application logic to validate and load data is provided by the Application Programming Interface code (APIs), i.e. not by the Gateway. The Gateway only populates the relevant Application Open Interface tables recognized by the APIs for the specific EDI message/transaction. Process Flow The Oracle Gateway performs the following functions during an inbound transaction process after it receives an interface file from the EDI Translator or other process: • Gets Trading Partner validation processing parameters • Applies code conversions (if set up and activated). • Loads valid data into the appropriate Oracle Application Open Interface tables for the transaction. • e-Commerce Gateway captures transaction data exceptions. These exceptions can be reviewed on-line from the staging tables to examine the exception condition. The correction action is performed in a trading partner set up or other application set up. The transaction can then be revalidated. Outbound Transactions For outbound transactions, the Gateway extracts the data from the base Application tables. Also, it may optionally extract data from other files/tables using the built-in extensible architecture using ‘Extension’ tables. The use of Extension tables requires customization of standard code packages provided with the Oracle Gateway if the user has need of this function. Process Flow The Oracle Gateway outbound transaction process creates interface data files to support any EDI Standard that is available from the EDI Translator. The Oracle Gateway collects all of the business data needed to map to a standard EDI transaction/message which the receiving Trading Partner can interpret properly into their receiving application using their equivalent of the Gateway/EDI Translator set up. The Oracle Gateway does the following: • Gets Trading Partner processing parameters, e.g. location codes, allowable/enabled EDI transactions/messages, etc., • Extracts data from the Oracle base applications tables relevant to the EDI transaction/message being processed. • Optionally, retrieves data from customer defined extension tables (requires some customization). • Applies code conversions (when set up and activated). • Populates Oracle Gateway interface tables with all the data gathered. • Sets the data extract flags in the base Oracle Application table to prevent subsequent extraction. • Produces an interface data file for use by the EDI Translator. Note The Oracle Gateway does not have communication software to transmit the standard formatted data between Trading Partners. The Oracle Gateway relies on the EDI Translator being connected to third party communication service providers to transmit data to, or receive data from, Trading Partners after the data is mapped to the desired standard format. http://appsinthebox.blogspot.com/2006/05/oracle-ecommerce-gateway-overview.html