OpenFL 1.2

The OpenFL v1.2 release contains the following updates:

• Long-living entities: Director/Envoy for supporting multiple experiments within the same Federation
• Scalable PKI: semi-automatic mechanism for certificates distribution via step-ca
• Examples with new Interactive API + Director/Envoy: TensorFlow Next Word Prediction, PyTorch Re-ID on Market, PyTorch MobileNet v2 on TinyImageNet
• 3D U-Net TensorFlow workspace for BraTS 2020 for CLI-based workflow
• AggregationFunction interface for custom aggregation functions in new Interactive API
• Autocomplete of fx CLI
• Bug fixes and documentation improvements