EPC GS1 Standard and RFID Encoding in Supply Chain

EPC (Electronic Product Code) and GS1 are two foundational standards for encoding data on RFID chip, allowing each product in the supply chain to have a unique identifier code, enabling automatic identification and traceability throughout. In Vietnam, adoption of these standards is accelerating as enterprises seek solutions for inventory control, loss prevention, and compliance with product origin traceability requirements from business partners.

#What are EPC and GS1? Their Role in RFID Encoding

EPC (Electronic Product Code) is a numbering structure developed by GS1, used to identify each individual product unit within the supply chain. GS1 is the global standards organization managing the barcode numbering system (UPC, EAN) and extending to RFID. EPC operates based on the EPC Gen2 protocol (ISO 18000-6C), optimized for high-speed batch reading.

The primary role of EPC/GS1 in RFID is creating a common language across the entire supply chain: from manufacturing, distribution centers, logistics hubs to retail points. Each RFID tag is encoded with EPC containing information such as company code, product code, and unique serial number. When read, the system can instantly look up detailed information from the database.

Compared to traditional barcodes, EPC RFID allows batch reading (up to 200 tags/second), requires no line-of-sight, and enables data rewriting. This reduces inventory time from hours to minutes, particularly useful in warehouse management and pallet inventory verification.

#EPC Gen2 Chip Memory Structure and Data Encoding Method

EPC Gen2 compliant RFID chips have four memory banks: Reserved, EPC, TID, and User. The EPC bank is where the main identifier code is stored – typically SGTIN-96 (96 bits) for retail or SGLN-96 for logistics. Each bank can be locked separately for security.

Memory Bank	Function	Capacity (bit)	Example
Reserved	Store password (kill, access)	64	Write protection password
EPC	Product identifier code	96-496	SGTIN-96: 3M.12345.67890
TID	Chip manufacturer code (immutable)	64-96	E2 00 40 01 (NXP)
User	Supplementary data (manufacture date, batch)	0-512	Batch: 2025-08, Exp: 2027-08

Typical EPC encoding method with SGTIN-96:

1. Header (8 bit): Determines format (SGTIN-96 = 0x30).
2. Filter (3 bit): Categorizes object (pallet, case, item).
3. Partition (3 bit): Divides ratio between company code and product code.
4. Company Prefix (20-40 bit): Company code assigned by GS1.
5. Item Reference (24-4 bit): Product code within company.
6. Serial Number (38 bit): Unique serial number for each unit.

Practical encoding workflow: enterprise inputs data from ERP or POS system, RFID software converts to EPC structure, writes to chip via RFID printer (example Chainway CP30), then verifies and locks EPC bank against rewriting.

#Specific Benefits of Implementing EPC/GS1 Standard in Supply Chain

Implementing EPC/GS1 encoding delivers three main benefits: inventory verification 10-20 times faster than barcodes, precise product traceability down to individual units, and reduced receiving errors through automatic reading without manual scanning.

• Warehouse Inventory: One staff member with Chainway C66 handheld RFID reader can inventory 500 pallets in 15-25 minutes, compared to 4-6 hours with barcode.
• Goods Receiving: RFID gate at dock door automatically reads entire pallet when passing through, matches against order in 3-5 seconds. Errors drop from 3-5% to below 0.1%.
• Product Traceability: Combined with EPCIS platform, enterprise can trace entire product journey from factory to retail shelf, meeting requirements from major retail chains.
• Counterfeit Prevention: Each tag has unique TID, combined with EPC, creates effective anti-counterfeiting layer for pharmaceuticals, functional foods, and luxury fashion.

#Comparison Table: EPC RFID vs Traditional GS1 Barcode

Though both part of GS1 ecosystem, EPC RFID and barcode differ significantly in reading capability, speed, and application. Below table provides detailed comparison.

Criteria	GS1 Barcode (EAN/UPC)	EPC RFID (Gen2 UHF)
Reading Method	Laser scan each code, requires line-of-sight	Radio wave, batch read without line-of-sight
Reading Speed	1 code/second	100-200 tags/second
Read Range	0-30 cm	3-12 m (UHF)
Data Capacity	13 digits (fixed)	96-512 bit + User area
Rewriting Capability	No	Yes (multiple times, if not locked)
Contamination/Damage Resistance	Easily torn, faded	High (water/heat resistant tags)
Cost (tag/label)	~100-300 VND	~1,500-5,000 VND
Primary Application	Retail, manual inventory	Automated warehouse, logistics, traceability

RFID tag cost is higher but ROI is clear when enterprise operates 500+ SKUs or has high inbound-outbound frequency. For fashion, food packaging, and pharmaceutical sectors, payback period typically 6-12 months through loss reduction and labor savings.

#Common EPC RFID Encoding Mistakes and How to Avoid Them

Many enterprises new to RFID make mistakes: duplicate serial number encoding, lack of data synchronization with POS/ERP system, or skipping verification step after writing. These errors reduce effectiveness and cause operational confusion.

• Duplicate Serial Number Encoding: Due to lack of centralized number management. Solution: use RFID management software (like 123RFID Desktop from Việt POS) to automatically generate unique serial numbers from ERP system.
• Ignoring TID Bank: Many focus only on EPC bank, but TID is chip's unique identifier, helping prevent counterfeiting and verify tag origin. Should read and store TID in database.
• Not Locking EPC Bank After Writing: Data can be overwritten. After verification, lock EPC bank (with 32-bit password) for security.
• Software-Chip Incompatibility: Some older chips don't fully support Gen2 commands. Check chip datasheet or select equipment from reputable vendors like Chainway, Zebra, Honeywell.
• Skipping Post-Print Verification: Printed tags must be read back for data verification. Use Chainway UR4 fixed reader integrated to conveyor line for automatic verification.

#Việt POS Implements Comprehensive RFID Solution to EPC/GS1 Standard

Việt POS provides comprehensive RFID solution from current state assessment, EPC structure consulting suitable for business, equipment installation (RFID printer, fixed/handheld reader from Chainway, Zebra, Honeywell) to integration with existing POS and ERP software, staff training, and 12-24 month warranty.

Việt POS implementation workflow:

1. Site Survey: Evaluate inbound-outbound-warehouse process, SKU count, transaction frequency, network infrastructure.
2. EPC Structure Consulting: Determine EPC format (SGTIN-96, SGLN-96, GRAI-96), bit allocation for Company Prefix, Item Reference, Serial Number.
3. Equipment Selection: Based on requirements: RFID printer (Chainway CP30), fixed reader (Chainway UR4/UR8), handheld reader (Chainway C66), RFID gate.
4. Software Integration: Connect RFID data with POS/ERP via API, sync inventory real-time.
5. Training and Handover: Guide operation, troubleshoot common issues, perform preventive maintenance.

With experience deploying solutions for many retailers, logistics, and manufacturing enterprises, Việt POS commits to GS1-compliant solutions, optimized cost and ROI timeline.

#Frequently Asked Questions about EPC, GS1 and RFID Encoding