Familiarize yourself with AS2 to help you decide whether this set of protocols is the right approach for your B2B data exchange needs.
There are numerous electronic data interchange protocols and frameworks, each designed to facilitate streamlined communication between trading partners. One of the most widely used protocols is Applicability Statement 2, commonly called “AS2.”
In this guide, we’ll discuss AS2 to help you determine whether this framework aligns with the needs of your organization and the requirements of your trading partners.
Q: What is AS2?
Applicability Statement 2 (AS2) is a protocol for securely exchanging EDI documents over the internet. It uses encryption and digital signatures to protect data, and provides a Message Disposition Notification (MDN) as a receipt, confirming delivery. AS2 is popular for its cost savings and reliability compared to older EDI methods.
Overview
Familiarize yourself with AS2, a secure data exchange standard that operates over HTTP or HTTPS. It ensures end-to-end encryption and reliability for B2B integrations.
What is the AS2 protocol?
AS2 is a transmission protocol. It uses HTTP or HTTPS to send EDI messages quickly and securely. ...
Retail and consumer goods businesses often rely on AS2 as their preferred EDI communication protocol due to its widespread adoption, notably led by Walmart. ...
You need an AS2 certificate to use these protocols. You can generate your own certificate with your preferred software. You can also use certificates from a third-party certification authority. Third-party certificates show you comply with the American National Standards Institute’s EDI communication standards.
ANSI creates and vets standards used in various industries, including the EDI protocols facilitating B2B communication between trading partners. This particular set of protocols is known as X12 EDI protocols.
AS2 vs. FTP, SFTP, and EDI VAN
Let's examine how AS2 compares to other common EDI communication frameworks:
AS2 vs. FTP
AS2 supplies built-in encryption and digital signatures, while standard FTP sends files in plain text. This immediate difference highlights AS2’s stronger security posture for data transfers.
File transfer protocol (FTP) is one of the most basic frameworks for exchanging data between two computers. Under this framework, users send and receive data in an unencrypted state.
FTP requires password and username authentication. It does not guarantee a secure connection. To secure your connection, you can use a virtual private network (VPN) or another security mechanism.
AS2 has more built-in security features than FTP. Many trading partners prefer AS2 for this reason. AS2 is often more cost-effective. You do not need to add extra security mechanisms.
AS2 vs. SFTP
Compared to FTP, secure file transfer protocol (SFTP) offers additional security by encrypting your data during transfer — similar to AS2. However, AS2 provides a few notable advantages, including the use of Message Disposition Notifications (MDNs) for non-repudiation, meaning both parties receive cryptographic proof that a document arrived intact.
Namely, SFTP doesn’t require you and your trading partners to share digital certificates before opening a connection. Instead, it relies on public or private keys for authentication.
EDI VAN vs. AS2
AS2 facilitates communication between two devices or systems on different networks by providing a unified set of standards and rules, and it is often adopted to bypass the high fees associated with traditional value-added networks (VANs). Conversely, EDI value-added networks (VANs) provide trading partners with a dedicated, secure communication network.
With an EDI VAN, each authorized company has its own mailbox for exchanging various EDI documents, including invoices and purchase orders.
AS2 offers solid security and cost-effective implementation. While VANs provide enhanced security, they typically involve lengthy, complex implementations that can delay your trading partner connections.
How does AS2 Work?
AS2 provides an envelope of security and reliability for file transfers between trading partners.
- Configure your AS2 software.
- Exchange certificates for encryption and signing.
- Send and receive EDI messages via HTTPS.
- Verify receipt with MDNs and logs.
Key Takeaways
The AS2 protocol offers a standardized, cost-effective solution that ensures secure transfers and non-repudiation.
What is an AS2 MDN?
An AS2 MDN (Message Disposition Notification) is a digital receipt confirming the recipient received your message. It can include a Message Integrity Check (MIC) and a digital signature, supporting non-repudiation and retries if needed.
Both parties must be online during an AS2 exchange, as undelivered messages can’t be stored on a server or digital mailbox. If one party is offline, the message is lost and must be resent.
AS2 requirements
AS2-based communication requires several tools and credentials:
- An AS2 identification (Global Location Number, or GLN)
- Public keys for each of your partners’ certificates
- AS2-capable software
- AS2 certificates
What are AS2 certificates?
AS2 certificates facilitate secure data exchange and ensure you meet certain security standards. As mentioned, you can obtain third-party AS2 certificates or issue and sign your own. Third-party certificates are generally considered more secure than certificates you issue and sign yourself.
AS2 benefits
AS2 is widely used in the retail and consumer goods sectors due to its interoperability, cost-effectiveness, and high security (including 256-bit encryption and non-repudiation).
- Secure transport (HTTPS/S/MIME)
- Traceability with message disposition notifications
- Compliance with industry regulations
AS2 disadvantages
Potential disadvantages of AS2 include the following:
Direct, continuous internet connection required; Need to exchange keys; Labor-intensive maintenance processes; Regular certificate renewal; Firewall configuration complexity
- The need to exchange keys
- Labor-intensive maintenance processes
These potential drawbacks will also impact your trading partners. You should also consider their needs when determining the best solution.
The role of AS2 in EDI
AS2 is often mentioned in the same breath as EDI due to its ubiquity in the retail and consumer goods industries. To maintain interoperability, many software providers submit their implementations for Drummond certification — an independent test suite that verifies conformance to the AS2 standard. AS2 is a communication protocol that facilitates the secure transmission of EDI documents, but it isn’t the only framework available. It’s not even the most recent applicability statement.
Released just over a decade ago, Applicability Statement 4 (AS4) became an ISO standard in 2020. This modern iteration of the applicability statement protocol set includes additional provisions to enhance security and streamline communication, including SOAP-based receipt acknowledgments with XML digital signatures.
AS4 became an ISO standard in 2020 (ISO 19845:2020). For more on X12 standards, see ANSI X12 (ANSI 2024). Recent data shows retail adoption of AS2 remains high (Gartner 2024).
Is AS2 the right solution for your business?
AS2 and AS4 protocols are widely used in retail and consumer goods for EDI transmissions. For supply chain and logistics companies, the key considerations are how quickly you can onboard trading partners and how much integration overhead these protocols require.
Leveraging a modern EDI solution like Orderful’s can transform your business and allow you to overcome the limitations of the AS2 protocol.
Contact us today to talk to an expert and learn more about our EDI solutions. Our knowledgeable team will help you proactively avoid major time-wasters during your EDI implementation so you can enjoy the benefits in days, not months.
AS2 FAQs
What is AS2 in EDI?
AS2, or Applicability Statement 2, is a secure communication protocol used to exchange EDI documents such as purchase orders and invoices over the internet. It provides encryption, digital signatures, and message receipts to ensure data security and integrity.
What is an AS2 Identifier (GLN)?
An AS2 Identifier, often the same as your GLN, is a unique string used to identify a trading partner’s AS2 endpoint. It ensures messages are routed correctly and helps validate partner identity.
How does AS2 work?
AS2 transmits business documents over HTTPS using certificates for encryption and authentication. When a document is sent, the receiving system returns a Message Disposition Notification (MDN) to confirm receipt. This process makes AS2 highly reliable for EDI communication.
Why do companies use AS2 for EDI?
Companies use AS2 because it is secure, standardized, and widely adopted by large retailers, logistics providers, and manufacturers. It reduces reliance on third-party networks and allows businesses to exchange data directly with their partners in real time.
What is an AS2 MDN?
An AS2 MDN, or Message Disposition Notification, is a receipt sent back to the sender confirming that the message was received successfully. MDNs are critical for ensuring compliance and for validating that no data was lost in transmission.
How is AS2 different from SFTP or FTP?
AS2 provides stronger security features than FTP or SFTP. While FTP and SFTP focus on file transfer, AS2 adds encryption, digital signatures, and signed receipts, making it the preferred choice for industries with strict compliance requirements.
What are common AS2 errors and how can they be fixed?
Common AS2 issues include certificate mismatches, expired certificates, incorrect AS2 identifiers, or connectivity problems. These are usually resolved by updating certificates, verifying identifiers, and checking communication channel configurations.
What is required to set up an AS2 connection?
To set up AS2, you need an AS2 identifier, digital certificates for encryption and signatures, and an internet connection over HTTPS. Both trading partners must agree on configuration details, such as endpoint URLs and security settings.
To better understand the basics of how these protocols facilitate business-to-business data exchange, see our guide on communication channel basics.
There are several types of EDI protocols and frameworks, each designed for different business needs and technical environments.
For more information about identifying and selecting the right communication methods for your integration, refer to identifying communication channels.
If you are troubleshooting issues with AS2 connections, consult our AS2 troubleshooting documentation.
For organizations exchanging documents using FTP or SFTP, see our resources for inbound FTP and SFTP and outbound FTP and SFTP integrations.
If you need to share Orderful's AS2 information with non-Orderful users, review our Orderful AS2 information for non-Orderful users.
For more insights and updates, explore our blog archive.
