🚀 go-pugleaf

Hello all,

I would like to know of other people's thoughts in using Estelle, LOTOS or Z
in the specification and implementation of OSI application layer services. 
The idea is to use these languages is not just in the specification of the 
services and protocols, but also in the implementation by the use of a
compiler to C or C++ (for example). The discussion should not be mainly 
concerned with the availability of a good compiler, but with the 
suitability of these languages in the implementation of the layer 7 services. 

Regarding the Estelle option, the software design should consider 
whether a mixed implementation should be used (i.e. there would  
be external data types and functions defined in another language), or would
Estelle be used completely as an implementation language. A mixed
implementation could use the strengths of Estelle to specify and implement
the components that it is especially good at, while using another language
for other operations. This appraoch may apply to other specification languages
as well (is this possible?).

Some specific questions which could be answered are:

	* Is a mixed implementation the best approach, or should the
	implementation be based entirely on the specification language.

	* If a mixed implementation is a good idea then what parts should the
	specification language be used for? How much of the software
	would this be approximately (e.g. 10%, 50%, 90%)?

	* How suitable are the languages for the implementation of
	OSI application layer services? For example, the implementation must 
	consider the protocol specification (a finite state machine)
	and the service specification. How useful are Estelle, etc., for
	these parts. Note that experiences in the lower layers may not
	necessarily apply directly to the application layer where there
	is perhaps a relatively smaller protocol specification, and a 
	greater service aspect.

	* Would anybody seriuosly consider implementing an application
	layer service using one of these specification languages?

	* Has anybody implemented an application
	layer service using one of these languages?

Please present other ideas if they are relevant. Also, refer to journal 
articles or other documents if they are useful in the discussion.


If there is plenty of interest then I will summarise the responses.


			-- thanks for your time, John Gottschalk

===================================================================== 
     John Gottschalk (john@citr.uq.oz) 
     Centre for Information Technology Research,
     The University of Queensland, 4072, 
     Brisbane, Queensland, Australia,
     +61 7 365 4321 (phone), +61 7 365 4399 (fax)
=====================================================================