Do I need a VAN, or can I use AS2?

Either works; the trading partner decides what it accepts. A VAN is a managed network that routes EDI between partners and charges by document or kilocharacter. AS2 is a direct point-to-point protocol over the internet with no per-document fee, but it requires certificate management and a connection configured per partner.

VAN costs scale with volume and AS2 costs scale with the number of partners. A brand trading heavily with three retailers usually prefers AS2; one trading lightly with twenty usually prefers a VAN.

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