Another designed three different telephone stations in various sizes, while AXE could be made smaller or larger as required.
One competitor believed that it was impossible to deliver systems as quickly as modularly tested, bug-free software modules allowed. As if that was not enough, modules could be switched from analog to digital, a change that came more quickly than expected.Įven competitors and researchers found it difficult to understand why AXE appeared to be able to handle everything. Another objective was that it should be possible to replace physical modules with new ones, since technology continued to advance and processors, for example, got faster and more powerful. That meant that these building blocks could be tested where they were manufactured, for example in Sweden, and if they worked there, they could then be shipped to Saudi Arabia or anyplace else. If a module had been made bug-free, it was safe.Īnother aspect of modular design was that the system should consist of standardized building blocks, even from a mechanical standpoint. No signal could be introduced that would result in changes in another module. And for every fault corrected, a popular rule of thumb held that two new ones would appear.Īn important aspect of the AXE project was therefore creating independent program modules that only communicated with each other in a standardized manner. A fault or a bug might result in a serious malfunction, but the visible fault did not necessarily reveal where the bug was located.
The result was called spaghetti code – if a change was made it one place, it could have effects in a completely different place. The problem was that with so many people involved, no one could maintain an overview.
These were also not your ordinary tailors. The software for a complete telephone station was not the job of one person, but hundreds. Designing software and hardware in modules, making square pegs to fit round holes, was regarded as wasteful.Ĭomputer programs were the custom-tailored component. The processors, the units that counted, structured and handled the signals, had limited capacity.
Processing power was still limited and data storage was expensive. The unique qualities of the AXE system’s design must be viewed against the background of what technology permitted when it was conceived. Modules are like factory clothing, predictably sized, good enough, but never as good as custom-tailored. Standards risk paralyzing technology by preventing innovative leaps that create new features. Scania, however, had few followers of its philosophy. With hindsight, nearly everything seems self-evident. Surely it must be better to distinguish between routine tasks and more specialized functions? After all, wasn’t that the key to Scania’s success as a relatively small truck manufacturer? Standardization, scalability and integration are also time-honored concepts that imply capacity for upgrades, an ability for the system to grow or contract without problems and for its ability to prevent faults from spreading.