Exams multiple Flashcards
(86 cards)
What is meant by access transparency?
Local and remote resources are accessed using the same operations
what is meant by location transparency?
Remote resources are accessed using location independent names
What is meant by concurrency transparency?
Processes can access resources without interfering with each other
What is meant by failure transparency?
Failures are concealed for the users of a resource
What is meant by replication transparency?
Users of a resource access it as if it was not replicated
What is significant for a client server architecture?
The client is the active part
What would we call a system where one node is always reacting on requests and other nodes only communicate with this node?
A client server system
What is significant for a peer-to-peer architecture?
All nodes are active and can be the initiator of operations
What do we know in a synchronous system?
The upper bound of the time to perform an operation
What is significant for an asynchronous system?
That the time to perform an operation does not have an upper bound
What do we call a system where the maximum times for operations and messages delivery are known?
A synchronous system
What is provided by UDP?
A best effort delivery of messages to a process
What is provided by TCP?
A full-duplex stream between two processes
Which address can be found in the TCP header?
The port numbers
What is significant for synchronous communication?
The send operation blocks and waits for the receive operation
What is significant asynchronous communication?
A sender can continue without waiting for the receive operation
Can a synchronous communication interface be used in an asynchronous way?
Yes, by performing the send operation in a separate thread
What is the difference between the two nodes that are communicating over a stream socket?
Nothing, they have equal rights and responsibilities
The erlang call gen_tcp:recv(Socket,0) will return
The first part(possibly the whole) message sent to Socket
What is the purpose of the marshaling procedure?
To encode application layer structures in an external form
How are arguments passed in Java RMI?
At most once
What level of transparency is provided by method invocation in Java RMI?
Location transparency only since we need to capture remote exceptions
What level of transparency is provided by method invocation in Java RMI?
Location transparency only since we need to capture remote exceptions
How do Erlang processes communicate?
Asynchronous message passing