[cap-talk] Capability levels

[Rob J Meijer]

>>...
>>Can we agree on
>>
>>   1. Hardware
>>   2. System language
>>   3. OS
>>   4. Application language
>>   5. Network
>>
>>?
>
> As I hope you can see from the above, for me a language is a
> language and OS and application level services exist at the
> same "level".  Capabilities can be conventions that are communicated
> within a shared memory protected domain (whether part of an
> operating system or some application) at what I consider the
> "language" level or across such protected domains within an
> IPC system (what I consider the "operating system" level)
> or across a network.  So for me the levels come down to:
>
> 1.  Hardware (if any domain separation, supported by hardware)
> 2.  Language (any separation of domains supported by shared libraries)
> 2.  IPC (any separation of domains supported by IPC mechanism)
> 3.  Network (separate domains on independent systems on the network)
>
> What do you think?  Is this just a difference of perspective (I'm
> looking at it one way, you another, but it's the same thing) or is
> there something fundamental about these distinctions and the
> "level"s.?
>
> Interesting discussion.
>
> --Jed http://www.webstart.com/jed/

I'm having a real hard time with folowing this discussion. Having given it
a few days to think about what bothers me. The first thing for what I needed
some time to sink in is terminology and the limited parsing capabilities
of my brain ;-)
The discussion often refers to 'the network layer' as the layer for network
capabilities as implemented in capability based language interpreters, but
unfortunately my brain seems to automatically parse 'network layer' in the
context of the OSI model layering sceme. Having said this, I hope you can
see that 'Network' as in OSI can be seen to define its own distinct
layering
model.
A further issue apeared to be related to the operating system and where it
should be seen in the layering. For me, as well as aparently others,
the hardware 'ring' layering that  CPU's provide, and the way they are
commonly used seems to have somehow gotten almost hardwired into my brain
adding to my confusion about the discussion.

Having come to grip with my initial confusion about the discussion I
think I must state that I believe that as there are different ways to
interleave both the CPU ring layering and the network OSI layering into a
particular layering of any capability system design, that I think any
attempt to define a 'generic' layering including hardware or network as
layers is simply useless (next to being hard on the brain)

Rob