Technical Design
Subphonic Transact is Azure native, designed for scale and resilience. Transact utilises the latest cloud-hosted technologies to deliver its platform and solutions. Transact is designed from the ground up with both massive scale and global reach as core design requirements.
The solution features:
- Multiple SBCs (no SPOF) in each region
- Resources to support 100% of the throughput in a single region
- Auto scaling or manual scaling at the click of a button within a region
- Incredibly efficient SIP Proxy service, only adding circa 3ms
- Redundant Azure services comprising of the public API, message processors, and PSP proxy services
- Native Azure services for Cache, Service Bus messages, real time capture state updates and logging
Application Overview
A step-by-step walkthrough of the Transact agent and customer experience — covering authorisation, Pay by Phone and Pay by Link journeys — along with the full configuration reference and every supported launch parameter.
Application Architecture
How Transact is built on Azure as a set of microservices behind an Application Gateway, with event-driven messaging, PSP adapter abstraction, and support for both phone and digital payment channels.
Telephony Architecture
The telephony deployment options, SBC topologies, and media handling strategies that secure live calls during card capture across public and private connectivity.
API Overview
The Transact API surface for programmatic integrations — authentication, card capture session management, and IVR-driven payment flows without the agent UI.
Security and Compliance
PCI DSS 4.0 compliance controls across the platform — scope minimisation, network segmentation, encryption in transit and at rest, access controls, secrets management, vulnerability scanning, and continuous monitoring.