I'd like to introduce everyone to our newest e-lang list member, HP's Chief Scientist of E-Speak Operations, Alan Karp.
Alan is the architect of HP's E-Speak system ( http://e-services.hp.com/ & http://www.e-speak.net/ ). E-Speak, like ELib, is a foundation for distributed systems of persistent communicating services. What is not obvious from these web sites is that all inter-service communications and security is based on cryptographic capabilities! From talking to Alan, it seems their notion of capabilities is very similar to our inter-Vat capabilities.
When I explain to Alan our thinking, I'm repeatedly pleased by the frequency with which I hear "Yup, we figured that out as well". This is unique in my experience among people that weren't schooled in KeyKOS/EROS or Vulcan/Joule/E. Alan came to capabilities by independently reinventing them. Curiously, at first he didn't think that what he'd invented was capabilities, as his invented primitive bundled together base capability properties with rights amplification.
The current version of E-Services, 3.01, has moved to using SPKI as its cryptographic capability system. It seems they also independently realized that SPKI is approximately a capability system.
E-Speak & E have many of the same architectural premises, but have been developed with very different engineering emphases. This makes it likely that they have complementary strengths and weaknesses. E-Speak is now open-sourced under LGPL & GPL, so there may be many opportunities for cooperation between the projects.
In addition to the similarities, in one crucial way E-Speak goes well beyond the engineering of any of the capability systems in our tradition: It incorporates, as part of its communications infrastructure, a description-matching search system for resource discovery -- matching a description of services desired with the description of services offered. Though Jini has made such abilities well known, no one else has figured out how to do this without violating security properties. I don't yet fully understand how E-Speak pulls this off, but I'm eager to find out.
Alan, welcome!
Cheers,
--MarkM