If you want to understand
Gled, read the
overview paper.
If you want to build and use
Gled, read
Gled
for the impatient and then the description of
Gled's
GUI.
The paradigms of Gled describe the
Gled system in a more relaxed way. It is
complemental to the
overview paper (although
similar in contents).
The LaTeX sources of the papers and talks are in
gled-papers.
Description of core functionality of Gled and basic ideas of the
implementation.
Abstract
Gled is an implementation of a hierarchic server--client model
written in C++, having an outside form of an object
oriented framework. Master server exposes its object space to its
first-level clients which in turn provide mirroring facilities to
second-level clients and also export their own object spaces. Each
client therefore plays a role of a client, a proxy and a server.
Infrastructure for propagation and broadcasting of method invocation
requests is provided and is general enough to allow for an efficient
access control. Synchronization of object spaces is achieved via
streaming of object graphs and a time-ordered delivery of method
invocation requests.
Objects can acquire their own threads to perform different tasks
such as computation, data acquisition & analysis or dynamic
visualization. The obtained results can be pushed to other computing
nodes or storage devices. As threads are spawned and controlled
by standard method invocation requests, schedulers & job control
mechanisms spawning across a whole Gled cluster can easily be
implemented.
On viewer level, Gled features automatically generated GUI widgets
and a sophisticated 3D rendering infrastructure.
Description of authentication and authorization mechanisms of the Gled
framework. Representation of users and groups within Gled object
spaces.
Abstract
Gled authenticates every server and viewer that connects into a
cluster and authorizes every method invocation request before it is
executed. A connection, represented as a MIR-emitting entity, is kept
apart from the identities it wields: authentication links the
connection to its primary identity by an RSA challenge-response
against public keys kept in a directory tree, and group identities can
be attached to it later. Authorization is done by MIR filters, which
are Gled objects themselves: each object can have its own filter, its
guard, and each queen has a protector for all objects in its
queen-space. A filter allows, denies or has no opinion, so filters can
be stacked into compound ones, and the queen's authorization mode,
alignment and default judgment decide how the guard and the protector
are combined. The paper describes these elements and procedures at the
level of the implementation.
The
Greed manifesto and the
Greed design documents; their sources are
in the
greed
repository.
gled