1. RDA3 high-level – API & architecture 26th JUNE 2013
Ilia Yastrebov BE-CO-IN

2. RDA3 High-Level - API & Architecture
RDA3 Design Principles
Functional aspects
Controls Middleware based on Device/Property model
Operations: GET, SET (sync and async), SUBSCRIBE
Enhanced runtime diagnostics & statistics
Technical aspects
C++ & Java support
Lightweight (minimum dependencies, small footprint)
Non-blocking communication
QoS guarantees (priorities for clients & subscriptions)
Scalable Half-Sync/Half-Async threading pattern
Sync: Event demultiplexer (Reactor)
Async: Message priority queue + Threadpool (Scheduler)
API based on interfaces and Dependency Injection
26th June 2013
RDA3 High-Level - API & Architecture

3. RDA3 High-Level - API & Architecture
RDA3 Architecture
Transport Layer
Implements P2P non-blocking request-reply communication
Wraps ZeroMQ behind the interface
Detects disconnections / Provides reconnection facilities
High Layer
Client and Server API
Maintains connection state & client sessions
Extensible protocol independent of TL
Serialization
Subscriptions (with notifications ordering)
Processing engine (scheduler)
Integrates with Directory Service and RBAC (authorization)
Implements QoS (client & subscription priorities)
Application
RDA3
High Layer
Transport
ZeroMQ
26th June 2013
RDA3 High-Level - API & Architecture

4. Client API: Request-Reply (GET & SET)
26th June 2013
RDA3 High-Level - API & Architecture

5. Client API: Subscriptions
26th June 2013
RDA3 High-Level - API & Architecture

6. RDA3 High-Level - API & Architecture
Client Flow Diagram
26th June 2013
RDA3 High-Level - API & Architecture

7. RDA3 High-Level - API & Architecture
Subscription States
26th June 2013
RDA3 High-Level - API & Architecture

8. Server API: Request-Reply
26th June 2013
RDA3 High-Level - API & Architecture

9. Server API: Subscriptions
26th June 2013
RDA3 High-Level - API & Architecture

10. RDA3 High-Level - API & Architecture
Server Flow Diagram
26th June 2013
RDA3 High-Level - API & Architecture

11. RDA3 High-Level - API & Architecture
Serialization
Evaluated several 3rd party solutions
Google Protobuf (IDL based, huge project)
MessagePack (no IDL, many deps, slow for double arrays)
Ended up with home-made serialization
Small project, easy to implement
No dependencies
Performance gain
Data object with 3 arrays (int[], double[], String[]) of 40 elements each. Results for serialization+deserialization iterations
26th June 2013
RDA3 High-Level - API & Architecture

12. RDA3 High-Level - API & Architecture
Conclusions
Alpha version of RDA3 Client & Server is done for Java
Work on RDA3 C++ Server is in progress
Plan to release alpha version in July 2013
Work in close collaboration with users
Regular meetings with most important users
Presented all components of RDA3, approved by clients
API was reviewed and approved by all major users
Questions?
26th June 2013
RDA3 High-Level - API & Architecture