JP, what do you mean by 'SOA-based designs introduce agility'? 'agility' to what? Why SOA-based designs introduce it while it is known for years in the form of Adapters? I did the same thing (for market quotes) with Reuters and Morning Star 5 years ago in plain J2EE w/o any services...
- Michael ________________________________ From: jp_morgenthal <[email protected]> To: [email protected] Sent: Wednesday, May 13, 2009 12:26:52 PM Subject: [service-orientated-architecture] Re: JP on defining SOA Well, since the thread was based on my blog entry, let me reiterate the part of my definition that is pertient here: "SOA-based designs introduce agility by enabling interchangeability of service providers without requiring process changes in the consumers" This is exactly the example I gave with UPS and FedEx for shipping. The overall process does not need to change. I intimated nothing about the implications within a single step. Returning to my UPS/FedEx example, there is an impact in which shipper to choose, but even that can be parceled out as a service that decides for you and fills in the correct shipping label. Ultimately, tho, you have to hand the box to the right shipper, which means something will change at the task level, but it need not impact the entire process. JP --- In service-orientated- architecture@ yahoogroups. com, "Rob Eamon" <rea...@...> wrote: > > JP, > > That's a good example. I suppose there may be others as well. > > I wonder how many such identical (or close enough) services might a typical > company encounter in their service portfolio. > > But I think I erected a strawman anyway. The original point by Ashraf was to > be able to change the implementation, which is different from swapping one > out for another. > > -Rob > > > --- In service-orientated- architecture@ yahoogroups. com, "jp_morgenthal" > <jpmorgenthal@ > wrote: > > > > Rob, > > > > Your pragmatism is partially correct here, but the effort need not be > > significant. From my favorite example, consider switching from FedEx to > > UPS for shipping. Most companies do this hundreds of times a day and the > > difference is how they prepare the package for shipping, which ultimately > > comes down to prepping the shipping label information. Yet, you can run > > the shipping process identically and choose a different shipping provider > > based on price with minimal overhead and effort as a single step. > > > > JP > > > > --- In service-orientated- architecture@ yahoogroups. com, "Rob Eamon" > > <reamon@> wrote: > > > > > > In other words, service interface is separate from service > > > implementation? This is the core SO principle. > > > > > > I'm still bearish on the notion that a service implementation can be > > > swapped out for another with zero consumer impact. I've never seen a > > > meaningful implementation of anything be swapped out without significant > > > effort. Some low-level technical components can and have been swapped out > > > but that's not the level we're addressing here? > > > > > > -Rob > > > > > >
