What is AS2?

Overview

AS2 (Applicability Statement 2) is a http based protocol to transmit messages (especially EDI messages) safely, cheaply and quickly. In the last 20 years AS2 has become the most widely used protocol for EDI in many industries, such as the retail and the consumer goods industry.

How does AS2 work?

To establish an AS2 connection you need two computers, a server and a client. Both connect to the Internet via a point-to-point connection. In order to transmit the desired data, AS2 creates an ‘envelope’ that enables secure transmission via the Internet using digital certificates and encryption.

What is an AS2 MDN?

MDN (Message Disposition Notification) is an electronic acknowledgement of reception that is sent to the sender via AS2 after an electronic message has been sent. This acknowledgement of reception confirms that the message has been transmitted completely.
    
The MDN mainly checks two things:

1. Whether the AS2 transfer was successfully completed
2. The message arrived at the desired recipient without change

The process of establishing an AS2 MDN connection is as follows:

1. The sender sends an encrypted EDI message with digital signature to the desired recipient
2. Transmission of the EDI message over the Internet via AS2
3. Message is decrypted by the recipient and the digital signature of the sender is verified
4. Recipient prepares the requested MDN and applies a digital signature. It is then sent back to the sender
5. Sender receives the MDN and verifies the digital signature of the recipient

What you need for AS2?

• One AS2 identification (GLN - Global Location Number), and one certificate per participant
• The public keys of all certificates used by your partners
• AS2 capable software

What are AS2 Certificates?

AS2 certificates are important because they enable secure data exchange and meet certain security standards. You can generate and sign your certificates yourself using software of your choice, or use certificates issued and verified by a trusted certification authority. These are exchanged in advance with the partner.

However, self-signed certificates can cause security warnings and thus disrupt the exchange of EDI messages.

What are the benefits of AS2?

• High level of security, as the data is encrypted
• Cost-effective, as the transmission takes place via the Internet
• Synchronous response to a transmission (real-time status)
• Can be used almost everywhere

What can be possible disadvantages?

• Bilateral partner management (point-to-point connection, exchange of keys)
• Open ports for AS2 communication on the firewall
• High maintenance effort, due to many signed certificates of Trading Partners and/or yourself which will expire and need replacing over time.

SEEBURGER offers a solution to address the problem of expired certificates and the efficient handling of multiple connections:
B2B routing is a communication service and takes over the delivery of all EDI messages from/to your B2B partners.

The resulting advantages are:

• safety
• simplicity
• low cost

The connection to the SEEBURGER Cloud is also possible via one single AS2 connection.

What is an AS2 GLN?

GLN (Global Location Number) is a 13-digit number that uniquely identifies a company. Nowadays more and more (mostly larger companies) rely on the use of GLN numbers to prevent confusion between companies. The GLN numbers are assigned by GS1, a global non-profit organization, which ensures that no GLN number is assigned twice and thus avoids confusion.