Re: High-integrity networking

[Maciej Sobczak <see.my.homepage@gmail.com>]

On 8 Pa , 18:03, Colin Paul Gloster <Colin_Paul_Glos...@ACM.org>
wrote:

> |----------------------------------------------------------------------|
> |"Ravenscar describes the language subset and the usage patterns for   |
> |multitasking within a single process."                                |
> |----------------------------------------------------------------------|
>
> RAVENSCAR is not about patterns. I do not believe that even Tullio
> Vardanega claimed that in his paper "Ravenscar design patterns?:
> reflections on use of the Ravenscar profile".

I didn't mean "design patterns", but "usage patterns" in the sense
that some things are discouraged/forbidden and some others are
promoted/enforced.

> A RAVENSCAR task is a process. Multiple threads inside one process are
> not possible in RAVENSCAR.

Could you please throw some references? A relevant citation from the
Ravescar document itself would be perfect.

I have found *one* paragraph indicating that tasks are single-threaded
and *many* paragraphs about shared variables, global data, and so on.

As far as I'm concerned it does not really matter how the program is
deployed on the given system - and if it's deployed on bare metal (no
OS underneath), then the distinction between processes and threads
does not make any sense anyway.

The only thing I find important is that the complete Ravenscar
program, comprising potentially many tasks, is a *single entity* from
the deployment point of view - whatever that means on the given target
platform.

But I'm not asking about Ravenscar.

> |----------------------------------------------------------------------|
> |"I'm interested in patterns and solutions for high-reliability        |
> |networking/middleware.                                                |
> |                                                                      |
> |Just "extrapolating" Ravenscar to the distributed environment can lead|
> |to some imaginably constrained environment where [..]                 |
> |[..], the types (and lengths) of messages are                         |
> |known up front, etc.                                                  |
> |There are some start-up issues with ensuring all these constraints    |
> |(for example, the locations of other nodes would need to be first read|
> |from some configuration file/database before the connections can be   |
> |established, etc., [..]                                               |
> |                                                                      |
> |[..]"                                                                 |
> |----------------------------------------------------------------------|
>
> RAVENSCAR is not intrinsically specific to the packet-switching
> paradigm.

I'm not asking about Ravenscar. I'm asking about recommended reading
in the area of high-integrity networking and middleware. I have
mentioned Ravenscar to give you a hint on what is the kind of document
that could be the closest analogy to what I'm looking for.

Any recommendations?

--
Maciej Sobczak * www.msobczak.com * www.inspirel.com