Joint Architecture Standard Overview Profile
JAS versus PROPIN Trade Study
Feature Comparison
JAS has a number of positive impacts on budget, schedule, and performance. Below is a table that illustrates these advantages when comparing a JAS-based system to a PROPIN approach.
Advantage | Benefit | Budget | Schedule | Performance |
Scalable processing systems | Ability to add/remove as many nodes as are needed to support large or small systems | Good | Best | Best |
Standard processing elements | Unique node designs with capability to expand as needed | Best | Best | Good |
Standard communication interfaces | Enabling different vendors to be able to communicate with each other | Best | Best | Good |
Reduce SWaP | Modular design allows scalability to the specific mission SWaP and performance requirements | Better | Good | Best |
M-of-N redundancy | Reduce the number of spares that are needed in case of a fault | Best | Good | Good |
Utilizing industry standards | Rather than coming up with proprietary solutions | Best | Best | Good |
Future-Proof | Ability to easily support future technology and still be backward compatible | Best | Best | Best |
JAS vs. PROPIN Feature Comparison
Trade Study Example
The below example is a trade study which took a legacy program and redesigned it using the JAS architecture. The legacy program had several teams working independently which resulted in multiple different proprietary solutions. The JAS-based program uses common design infrastructure to integrate team methodology.
Item | PROPIN | JAS | Savings | Notes |
Processing Elements | 40 | 19 | 52% | JAS –3 nodes, 16 MEZ/RTM designs; PROPIN – 40 unique board designs |
Communication Interfaces | 14 | 7 | 50% | JAS –SpaceWire & SRIO network, external interfaces; PROPIN – All internal interfaces custom |
Communication Protocols | 20 | 5 | 75% | JAS – 5, significant reuse of flight software; PROPIN – 20 custom communication links |
Flight Boxes | 17 | 7 | 59% | JAS – 7 boxes (3 node stacks w/ common electronics); PROPIN – 17 unique boxes |
Flight Cables | 132 | 65 | 51% | JAS – ~65 (45 Electrical, 20 Fiber); PROPIN – +132 ( +122 Electrical,10 Fiber) |
Payload Weight | 750lbs | 500lbs | 33% | JAS – Optimized electro-mechanical design; PROPIN – Large number of independent designs |
Payload Budget (Equivalent Year) | ~$500M | ~$350M | 30% | JAS – significant REC in electro-mechanical design; PROPIN – Large NRE cost |
Payload Schedule | 84 mo. | 48 mo. | 42% | JAS – significant reuse of hardware and software IP; PROPIN – Fully custom due to mission requirements |
JAS vs. PROPIN Trade Study
These savings were realized by adopting the following JAS methodologies:
- Minimizing node types
- Maximize reuse of nodes by utilizing both MEZ and RTM expansion modules
- Distributed node stacks connected via simple bus power and network cables
- Common interfaces and protocols simplifies payload at every level of integration (hardware, physical, logical, application….)