AS2 (Applicability Statement 2) is a specification for secure Electronic Data Interchange (EDI) over the Internet. It uses HTTP/HTTPS for transport and provides encryption, digital signatures, and non-repudiation through MDN receipts. Major retailers like Amazon, Walmart, and Target require AS2 for vendor communications.

Frequently Asked Questions

Q: What is the difference between AS2 and SFTP?

AS2 provides built-in encryption, digital signatures, and delivery receipts (MDN), making it ideal for B2B EDI where non-repudiation is required. SFTP is simpler but lacks native receipt acknowledgment. AS2 is required by most major retailers for EDI, while SFTP is more common for general file transfers.

Q: How much does Serverless AS2 cost?

Serverless AS2 is free and open source. Running costs on AWS are $0/month on Free Tier for low-volume usage. For 1,000 messages/day, expect approximately $1-3/month. This compares to $220+/month for AWS Transfer Family or $500-2000+/month for commercial solutions.

Q: How long does it take to deploy Serverless AS2?

Serverless AS2 deploys in approximately 15 minutes using a single command. Run 'curl -fsSL https://serverlessas2.io/install.sh | bash' in AWS CloudShell to automatically provision all required AWS resources.

Q: What trading partners work with Serverless AS2?

Serverless AS2 works with any AS2-compliant trading partner. It has been production-proven with Amazon Vendor Central, Rithum (CommerceHub), Mirakl, LogicBroker, Target, OpenAS2, and many others.

Q: What is an MDN in AS2?

MDN (Message Disposition Notification) is a signed receipt that confirms successful delivery and processing of an AS2 message. It provides non-repudiation - proof that your trading partner received the message. MDNs can be synchronous (immediate) or asynchronous (delayed).

Q: How does Serverless AS2 compare to AWS Transfer Family?

Serverless AS2 costs $0 on Free Tier vs $220+/month minimum for AWS Transfer Family. Serverless AS2 is open-source with a web UI, while Transfer Family has limited configuration options. Both run on AWS with similar reliability, but Serverless AS2 uses pay-per-use pricing.

Q: Is Serverless AS2 secure?

Yes. Serverless AS2 supports industry-standard encryption (AES-128, AES-192, AES-256, 3DES) and signing algorithms (SHA-1, SHA-256, SHA-384, SHA-512). All data is encrypted in transit and at rest. Certificates and private keys are stored securely in AWS.

Find answers to common questions about AS2, EDI, and Serverless AS2.

What is AS2?

AS2 (Applicability Statement 2) is a specification for secure Electronic Data Interchange (EDI) over the Internet. It uses HTTP/HTTPS for transport and provides:

Encryption - Messages are encrypted using S/MIME (AES, 3DES)
Digital Signatures - Messages are signed to ensure authenticity
Non-repudiation - MDN receipts prove message delivery
Reliability - Built-in retry and acknowledgment mechanisms

Major retailers like Amazon, Walmart, and Target require AS2 for vendor communications because it meets compliance requirements for secure B2B data exchange.

What is the difference between AS2 and SFTP?

AS2 and SFTP are both secure file transfer protocols, but they serve different purposes:

Feature	AS2	SFTP
Delivery Receipt	Yes (MDN)	No
Non-repudiation	Yes	No
Digital Signatures	Built-in	Requires additional setup
Retailer Compliance	Required by most	Sometimes accepted
Complexity	Higher	Lower

Bottom line: Use AS2 when your trading partner requires it (most major retailers) or when you need proof of delivery. Use SFTP for simpler file transfers where receipts aren't required.

How much does Serverless AS2 cost?

Serverless AS2 is free and open source. Your only costs are AWS infrastructure usage:

Usage Level	Monthly Cost
Low volume (Free Tier eligible)	$0/month
~100 messages/day	~$0.50/month
~1,000 messages/day	~$1-3/month
~10,000 messages/day	~$10-20/month

Compare this to $220+/month for AWS Transfer Family or $500-2000+/month for commercial solutions like Cleo or IBM Sterling.

How long does it take to deploy Serverless AS2?

Serverless AS2 deploys in approximately 15 minutes using a single command:

curl -fsSL https://serverlessas2.io/install.sh | bash

The installer automatically provisions all required AWS resources:

API Gateway for HTTPS endpoints
Lambda functions for AS2 processing
DynamoDB tables for configuration and tracking
S3 buckets for message storage
CloudFront distribution for the web UI

What trading partners work with Serverless AS2?

Serverless AS2 works with any AS2-compliant trading partner. It has been production-proven with:

Amazon Vendor Central
Rithum (formerly CommerceHub)
Mirakl
LogicBroker
Target
OpenAS2
And many more...

If your trading partner supports AS2, Serverless AS2 can connect to them.

What is an MDN in AS2?

MDN (Message Disposition Notification) is a signed receipt that confirms successful delivery and processing of an AS2 message. It provides non-repudiation - cryptographic proof that your trading partner received the message.

MDNs can be:

Synchronous - Returned immediately in the HTTP response
Asynchronous - Returned later via a separate HTTP request

Serverless AS2 supports both types and automatically tracks MDN status in the TrackLog.

How does Serverless AS2 compare to AWS Transfer Family?

Feature	Serverless AS2	AWS Transfer Family
Monthly Cost (Low Volume)	$0 (Free Tier)	$220+ (always-on)
Cost per Message	~$0.001	$0.01
Open Source	Yes	No
Web UI	Full-featured	Limited (AWS Console)
Setup Time	15 minutes	Hours
Pricing Model	Pay-per-use	Always-on + per message

Is Serverless AS2 secure?

Yes. Serverless AS2 implements industry-standard security:

Encryption algorithms: AES-128, AES-192, AES-256, 3DES
Signing algorithms: SHA-1, SHA-256, SHA-384, SHA-512
Transport: HTTPS (TLS 1.2+)
Storage: Encrypted at rest in S3 and DynamoDB
Keys: Private keys stored securely in AWS

All data stays in your AWS account - we never have access to your messages or credentials.

Can I use my own domain?

Yes. You can configure a custom domain for your AS2 endpoint by:

Creating a certificate in AWS Certificate Manager
Adding your domain to CloudFront
Updating your DNS to point to CloudFront

Your AS2 URL will then be https://as2.yourdomain.com/receive instead of the default CloudFront URL.

What happens if a message fails?

Serverless AS2 handles failures gracefully:

Automatic retries - Failed outbound messages are retried with configurable intervals
Error tracking - All errors are logged in the TrackLog with detailed information
Notifications - Configure SNS alerts for failed messages
Manual retry - Resend failed messages from the web UI

What file formats are supported?

AS2 is format-agnostic - it transports any file type. Common EDI formats include:

ANSI X12 (850, 810, 856, etc.)
EDIFACT
XML
JSON
CSV
PDF, images, and other binary files

Message Tracking

Glossary