Habitat is a "multi-player online virtual environment", created by Lucasfilm Games, a division of LucasArts Entertainment Company, in association with Quantum Computer Services, Inc. It was arguably one of the first attempts to create a very large scale commercial multi-user virtual environment in 1985. The system we developed could support a population of thousands of users in a single shared cyberspace. Habitat presented its users with a real-time animated view into an online simulated world in which users could communicate, play games, go on adventures, fall in love, get married, get divorced, start businesses, found religions, wage wars, protest against them, and experiment with self-government. Our experiences developing the Habitat system, and managing the virtual world that resulted, offer a number of interesting and important lessons for prospective cyberspace architects. The purpose of this paper is to discuss some of these lessons. We hoped that the next generation of builders of virtual worlds can benefit from our experiences and (especially) from our mistakes.

Abstract. Every novel cooperative arrangement of mutually suspicious parties interacting electronically -every smart contract -effectively requires a new cryptographic protocol. However, if every new contract requires new cryptographic protocol design, our dreams of cryptographically enabled electronic commerce would be unreachable. Cryptographic protocol design is too hard and expensive, given our unlimited need for new contracts.Just as the digital logic gate abstraction allows digital circuit designers to create large analog circuits without doing analog circuit design, we present cryptographic capabilities as an abstraction allowing a similar economy of engineering effort in creating smart contracts. We explain the E system, which embodies these principles, and show a covered-call-option as a smart contract written in a simple security formalism independent of cryptography, but automatically implemented as a cryptographic protocol coordinating five mutually suspicious parties.

This article describes the Lucasfilm company's Habitat project, one of the first attempts to create a large-scale, many-player, graphical environment. Functioning on personal computers such as the Commodore 64, Habitat can simulate virtual worlds in real time for thousands of users. This avant-garde experiment provides insight into the development of communities in cyberspace by demonstrating the necessity of a shared environment. The authors show that cyberspace is defined more by the interaction between participants than by the technology itself. In this context central planning is impossible, if not futile. It is therefore essential to provide participants with varied capabilities for interaction, enabling them to model the world in which they live. An object oriented model is a central element in the project. Finally, given the complexity and the changing nature of virtual worlds, the authors suggest that the architects of cyberspace could learn as much from the principles of sociology and economics as from the principles of computer science.

No abstract