WS Transportation Brought AS2 In House On Files.com To Prove Failures And Onboard Partners Directly

WS Transportation is a British road transport and logistics group operating across the UK and Europe. Its consumer-facing arm, WS Home Delivery, handles warehousing and final-mile delivery for retail customers: retail orders flow into WS's systems, and confirmation documents and proof-of-delivery returns flow back out as files exchanged with each retailer's own systems.

That exchange is EDI, and in retail, EDI usually means AS2: the signed, encrypted, receipted protocol large retailers require of their trading partners. WS ran its partner SFTP exchange on Files.com. Its AS2 connections lived somewhere else, with a third-party hosted EDI supplier hired to carry the protocol. That arrangement made sense for a small IT team, because running AS2 in house has traditionally meant operating an AS2 server and managing certificates with every counterparty. It also meant that the connections WS's retail business traded on sat in a vendor's hands.

To keep growing, WS needed those AS2 connections on the Files.com site it already operated: under its own control, independently testable when failures were disputed, and ready for its two-person team to extend to new partners.

A Broken AS2 Connection The Supplier Would Not Fix

The supplier's AS2 configuration was not working correctly, and the supplier was unwilling to troubleshoot its own setup. That left WS in the worst position a trading partner can occupy. AS2 is a two-party protocol: certificates, signatures, encryption and delivery receipts all have to line up with each counterparty, and when a transfer fails, each side can see only its own end. There is no neutral evidence for whose configuration is broken. So when partner traffic failed, the retail customers on the other end blamed WS for a fault inside a service WS was paying someone else to run, and WS had no way to prove otherwise.

WS wanted AS2 to support growth, not constrain it. The point was commercial: offer AS2 as an option to new retail customers and expand the base, with its own team standing up each new trading relationship.

An AS2 Endpoint WS Could Operate And Prove

The replacement had to be an AS2 endpoint WS controlled outright. Certificates it could generate, exchange and rotate itself. A signed receipt on every message, so delivery could never be disputed. A setup WS could test independently, so a failing connection could be pinned to the correct side before anyone assigned blame. And it had to sit beside the SFTP exchange WS's EDI already ran on, rather than adding a second platform for a two-person team to operate.

Files.com already carried that SFTP exchange, so WS Transportation stood AS2 up on the same site.

A Parallel Cutover, One Certificate At A Time

Stephen Hewertson, WS's Lead IT Engineer, generated and self-signed the certificates and exchanged them with each trading partner directly. The new endpoint came up in parallel with the failing supplier, and partner traffic moved across as each connection proved out. Files.com signed and encrypted every AS2 transmission and returned the MDN receipt the partner's software expected, so every message either came back confirmed or showed up as a failure to act on. WS put the endpoint behind its own domain and allowlisted dedicated Files.com IP addresses through the corporate firewall, giving the team an endpoint it could operate and test itself.

The team also adopted a validation step that became standard practice: before engaging a trading partner about a failing connection, run a test AS2 transfer against Files.com to prove WS's own side works, then take that proof to the partner. The first time it settled a dispute, the effect was immediate.

“Clearly the setup works, so just need to find out why they can't get it to connect”

Live Traffic, Provable Endpoints, And Direct Partner Onboarding

With AS2 running on Files.com, WS Transportation replaced a supplier it could not fix with a capability it operates itself.

• AS2 partner traffic was live and bidirectional by April 2023, moved across from the supplier to support the order, confirmation and POD flows running with retail customers.
• Fault disputes now open with evidence instead of blame. Ahead of the April 2024 certificate rotation, WS ran its validation step again: a working test transfer against Files.com proved its own certificate was correct, the trading partner produced the right certificate on its side, and the connection started working.
• Onboarding a new trading partner is now work WS does itself, by standing up an AS2 connection or an SFTP location on the same Files.com site. WS widened its protocol coverage from SFTP-only to SFTP plus AS2, and offers AS2 as an option when winning new retail customers.

AS2 As A Protocol, Not A Subscription

AS2 is usually treated as something a company buys from a specialist: an appliance in a rack or a hosted EDI service. WS Transportation treated it as one more protocol on the platform it already ran and took direct control of the connections its retail business trades on.