From Basic Principles of Java and Internet Security CPS616 Web Technologies -- Spring 98. byGeoffrey C. Fox
The processes comprising a computation will communicate by using a variety of mechanisms, including unicast and multicast.
While these processes form a single fully-connected logical entity, low-level communication connections (e.g., TCP/IP sockets) may be created and deleted dynamically during program execution.
Resources may support different authentication and authorization mechanisms and policies and we will have limited ability to change these.
Users will have different user ids on different resources.
Resources and users may be located in multiple countries.