Re: draft RFC: "umbrella"

["David L. Nicol" <david@kasey.umkc.edu>]

After thinking about this all weekend I realized two or three
places where it could be improved.  Also, I think a good first
couple of demonstrator items will be, a communications layer, because
that is so infrastructure that an explanation of Why I Left It Out is required,
and r* commands, that use the communications layer but could use another
communications layer that provided the same interface.

Why I Left Out A Communications Layer From Friday's Draft:

Because a general system needs to work with arbitrary communications systems!

Many are tied to ip address, for instance, but that breaks if part of your
cluster is behind a NAT firewall.  But if you are implementing an umbrella
module for compatibility with such a system, that is the communications you would
use.

I imagine a good communication layer might multiplex all communication between
any two nodes over one SOCK_STREAM that is between the two, or one for each level
of QOS, for instance a control channel and a bulk channel, like FTP, but reusing
the bulk channel.

With a multiplexed system that is hidden, a per-node open service, which opens
a new SOCK_STREAM to something on the other end, might be invoked with a syntax
that has two arguments, <service> and <path/filename> where <service> is some
information for the remote node as to what it is supposed to do with this new
connection and <path/filename> is a spot in the local file system where a unix
socket can be placed, for connection and use.


Thoughts?  How do you wrap a file name into a sockaddr, anyway?





> Capability management:

I left out "duplicate for persistent use" and "revoke" which are
additional capability primitives.


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