Amebo Operating System

Pointer to the object
Capability assigning right to perform to some operation to the object ticket
Communicate wide area network
a kind of ticket or key that allows the holder of the capa- bility to perform some (not neces- sarily all)
Each user process owns some collection of capabilities, which together define the set of objects it may access and the types of operations that my ne performed on each
After the server has performed the operation, it sends back a reply message that unblocks the client
Sending messages, blocking and accepting forms the remote procedure call that can be encapsulate using to make entire remote operation look like local procedure
Second field: used by the sever to identify which of its objects is being addressed server port and object number identify object which operation to performed
Generates 48-bit random number
The third field is the right field which contains a bit map telling which operation the holder of the capability may performed

Same process have multiple thread and each process has its own registered counter and stack
Behave like process
It can synchronized using mutex semaphore
File: Multiple thread,
Blocked when there's multiple threads
Buttlet thread the mutex
The careful reader may have noticed that user process can pull 813kbytes/sec

The V Distributed System

First tent in V design: High Performance communication is the most critical facility for distributed systems.
Second; The protocols, not the software, define the system.
Third; a relatively small operating system kernel can implement the basic protocols and services providing a simple network-transparent process, address space & communication model.

Designed for a cluster of workstations with high speed network access ( only really supports LAN ).
Abstract the physical architecture of the participating workstations, by defining common protocols providing well-defined interfaces.