Celsius Tech Bass Ch 15 Lecture by a

Celsius Tech Bass Ch 15 Lecture by a team from 2008 -9

Introduction • Celsius. Tech was a leading Swedish defense supplier – Owned by Saab AB • Main product line was Ship System 2000 (Mk 3) • Typically 1 to 1. 5 million lines of Ada running on 30 to 70 processors • Differing operator displays, hardware, and presentation languages • Sensors and weapons + interfaces vary • Runs on OS 2000, AIX, POSIX, Ultrix

Product Schedules

Code Reuse

Requirements and Qualities • Product line architecture • SS 2000 Qualities – Performance: Real-time – Modifiability: replacement of weapons/sensors, etc. – Safety, reliability, and availability – Testability: isolate errors quickly.

Physical Architecture

Process View • Multi-processing – Each CPU runs several Ada programs – Up to 300 programs total • Message Interface – Strong typing – Components are independent • Interprocess communication – Processes can run on any processor – Ada tasks for multithreading

Process View – Data Production • • Data is sent only when altered Data is presented as OO abstractions A component owns a given piece of data All data is accessible by all parts of the system Data is distributed Long-term data is kept consistent Data is checked for errors before being sent out

Process View

Layered View

Module Decomposition View • System function groups – Assignment for a particular development team – Each has its own requirements spec. – Consist of system functions • Software that implements some requirements – 30 groups, each with ~20 functions

Applying the Architecture • Architecture as the Foundation • Maintaining the Asset Base as New Systems are Produced • Maintaining Large Pre-integrated Chunks • Parameterized modules 1`

Summary • Celsius. Tech became a vendor of COTS naval systems • Architecture achieved “conceptual integrity” • Architecture evolve during validation • Overall a successful turnaround from a one-ata-time to a product line