Ashley, On Sep 26, 2005, at 12:20 AM, Ashley at Metamaxim wrote:
> Jan Algermissed wrote: > > > While I had thought there were only two possibilities, I actually > now > > see three: > > > > (1) The client knows the state machine of the service, > > that way knwoing what operations to call in what sequence > > > > (2) The client discovers the possible operations at runtime, using > > the message semantics (which it of course must understand) to > > choose what operations to call. (REST's application model) > > > > (3) [the new one] The client knows the sequence of operations the > > service will accept; in fact, the services are categorized > (typed) by > > these sequences and the client derives behavioral equivalence of > > the services from these types (the pi-/CSS-calculus approach). > > I am not sure I see any difference between (1) and (3). In (3), the > sequence of operations the service will accept must be specified by > a state machine (or something equivalent). This seems to make it > the same as (1). > > Or am I missing something? > Hmm...I guess you are right. I was thinking about the client making assumptions about the internal state, too (in 1) but now that you say it, I cannot remember why I thought that might be significant. But the question rally is: does the client have to know about the sequence of state operations in order to enable those complex business processes - I just cannot see why. All that happens is that the application logic gets hard-coded in the client and if the process changes, one needs to update the client. If the client determines the sequnce of operations at runtime, changes to the process do not affect the client *at all*. Jan > Rgds > Ashley > > > SPONSORED LINKS > Service-oriented architectureComputer monitoring softwareComputer > and internet software > Free computer monitoring software > > YAHOO! GROUPS LINKS > > Visit your group "service-orientated-architecture" on the web. > > To unsubscribe from this group, send an email to: > [EMAIL PROTECTED] > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. > > ________________________________________________________________________ _______________ Jan Algermissen, Consultant & Programmer http://jalgermissen.com Tugboat Consulting, 'Applying Web technology to enterprise IT' http://www.tugboat.de ------------------------ Yahoo! Groups Sponsor --------------------~--> Fair play? Video games influencing politics. Click and talk back! http://us.click.yahoo.com/T8sf5C/tzNLAA/TtwFAA/NhFolB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/service-orientated-architecture/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
