Golem's architecture is based on a modular design with the aim of providing decoupled and replaceable components. The primary building block is the Provider Agent application (ya-provider), which can be extended using pluggable ExeUnits.
ExeUnits are responsible for executing Requestors' code. Although conceptually similar to virtual machines, ExeUnits offer a broader range of utility.
Provider application consists of following components:
- Yagna daemon: It serves as the entry point to the Golem Network, providing APIs for communication between Nodes, handling market interactions, executing computations, and managing payments. It exposes a REST API for agent applications.
- Provider agent: This component is responsible for implementing the provider's business logic. It handles negotiation of Agreements on the market, spawns ExeUnits, and manages invoicing and payment reception.
- ExeUnit Supervisor: The ExeUnit Supervisor controls the ExeUnit Runtime and facilitates communication with the Yagna daemon.
- ExeUnit Runtime: This component is the implementation-specific part of the execution environment.
| From | To | Protocol |
|---|---|---|
| Provider Agent | Yagna daemon | REST API |
| Provider Agent | ExeUnit Supervisor | No communication (process is only spawned) |
| Yagna daemon | ExeUnit Supervisor | GSB (Unix socket / TCP depending on configuration) |
| ExeUnit Supervisor | ExeUnit Runtime | Unix socket, UDP or TCP (UDP by default) |
There are 3 communication channels between ExeUnit Supervisor and Runtime:
- Status and stdout/stderr channel output
- Outbound networking
- VPN traffic