Martin Geddes draws some interesting parallels between the telecom system/infrastructure and the UK railway system/infrastructure, and discusses some of the effects of economic and political incentives in both systems. He says there are no easy answers, not even easy questions.
I agree about the (lack of) easy answers, but I think there are some important questions. My first question is an architectural one - what is the geometry of the stack?
Getting the stack right isn’t easy. The UK rail system got it disastrously wrong. The rail company (formerly Railtrack, now Network Rail) bought rail maintenance services from engineering companies, and sold rail availability to train operating companies.
But the service level agreements didn’t add up. What service levels do you need from the engineering companies in order to guarantee a given level of rail availability to the train operating companies? And how do you verify that you are getting the required service levels? (These are what I call algebraic problems.)
This is an extremely complex business, for which the rail company lacked the necessary coordination capability. One of the consequences of this incompetence was a serious rail crash, caused by grossly inadequate rail maintenance. But this isn’t just a question of local incompetence. There is a fundamental architectural flaw in the design of the stack as a whole, which fails to tackle some serious and complex questions.
The architectural question here is not just the proper distribution of capability between the layers of the stack, but the bridging between radically different ontologies - the ontology of rail maintenance is quite different to the ontology of train operation.
So although I agree with Martin about the economic and political problems, I think there are some deeper structural (geometrical, architectural) problems which make it impossible to fix the system merely by tweaking the economics and politics.
Technorati Tags: architecture railway SOA service-oriented