Position paper

[Neal H. Walfield]

Marcus and I have written a short position paper [1] which we have
submitted to HotOS XI [2].

The goal of the paper is to articulate the problems we are trying to
solve (security, resource management and integration) and to outline a
framework for their solution.

The system we propose is capability based.  Such systems, it has been
shown, can be used to straightforwardly realize dynamic POLA and, when
designed carefully, can be made relatively extensible.  The fine
granularity attainable with capabilities is also desirable for
resource management.

To fix the resource management problems, we introduce an abstraction,
resource pools, which is similar to EROS's space banks or resource
containers.  Resource pools account resources and encapsulate a
resource scheduling policy.  Resource pools form a policy hierarchy
allowing tighter constraints to be placed on derived pools.  This
allows applications to decompose access to resources and refine policy
without having to resort to full-scale interposition.  In this way,
policy can be set according to the process hierarchy but realized by
the resource manager.  A practical implication is that the central
server can only implement a static number of policies reducing
generality.  We argue that, in practice, only a small number of
policies are actually required.  Finally, we introduce mechanisms to
allow applications to control multiplexing giving applications, in
particular, more control over the eviction policy.

Although the paper has already been submitted, we are still interested
in comments on how to improve it for the final version (if it is
accepted).  We are also very interested in discussing reactions to
this proposal.

Thanks,
Neal


[1] 
http://walfield.org/papers/20070104-walfield-access-decomposition-policy-refinement.pdf
[2] http://www.usenix.org/events/hotos07/cfp/