Editing Electronic Product Code (section)

== Structure ==

The canonical representation of an EPC is a [[Uniform Resource Identifier|URI]] - the 'pure-identity URI' that is intended for use when referring to a specific physical object in communications about EPCs among information systems and business application software.

Each coding scheme within the EPC identifier framework is distinguished through the use of a separate namespace. In the URI notations, this is indicated using a URI prefix such as <code>urn:epc:id:sgtin</code> or <code>urn:epc:id:sscc</code>
In the compact binary encoding of an EPC identifier, the namespace is instead indicated using a compact binary header (typically the first 8 bits of the binary encoding of an EPC identifier). The EPCglobal Tag Data Standard provides details of the URI prefixes and corresponding binary header values.

This namespace indicator (URI prefix or compact binary header value) in turn dictates the length, type and structure of the EPC. EPC encoding schemes are used to uniquely identify one object. Most EPCs include an element within their structure that corresponds to a serial number.

EPC Version 1.3 supports the following alternative coding schemes:
* General Identifier (GID) [[GID-96]]
* a serialized version of the GS1 Global Trade Item Number (GTIN) [[SGTIN-96]] [[SGTIN-198]]
* GS1 [[Serial Shipping Container Code]] (SSCC) [[SSCC-96]]
* GS1 [[Global Location Number]] (GLN), [[SGLN-96]] [[SGLN-195]]
* GS1 Global Returnable Asset Identifier (GRAI) [[GRAI-96]] [[GRAI-170]]
* GS1 Global Individual Asset Identifier (GIAI) [[GIAI-96]] [[GIAI-202]] and
* [[United States Department of Defense|DOD]] Construct [[DoD-96]]

From Version 1.4 these new coding schemas are also additionally supported:
* Global Service Relation Number (GSRN) [[GSRN-96]]
* Global Document Type Identifier (GDTI) [[GDTI-96]]