Quiz 4 Flashcards
Message brokers can provide the following:
a) Allows only synchronous communication between the producer and consumer
b) Transforms incoming messages to target format
c) Handle applications’ heterogeneity in a message queue system
d) Can route messages to consumers that subscribed to a particular topic
b) Transforms incoming messages to target format
c) Handle applications’ heterogeneity in a message queue system
d) Can route messages to consumers that subscribed to a particular topic
A process that pushes out its messages and does not care who pulls them but assume there are other processes that wants to pull in those messages can implement
a) Request-Reply pattern
b) Pipelining pattern
c) Publish-subscribe pattern
d) Topic-based pattern
b) Pipelining pattern
Message-oriented middleware allows communication between sender and receiver to be loosely coupled in time:
False
True
True
Communicating processes can form overlay network. Which of the following is/are true
a) Processes can use the overlay network to route messages to other processes in the overlay
b) Overlay network can only be formed by processes communicating over the local area network
c) Since the processes connect using the underlying network, their overlay network topology is always the same as their underlying physical network
d) Overlay network may span several physical networks
a) Processes can use the overlay network to route messages to other processes in the overlay
d) Overlay network may span several physical networks
An overlay network with a stretch of 2.0 between two connected nodes means:
a) the underlying network has a delay cost to route message between the two nodes that is the same as the delay cost of the overlay network
b) the overlay network has a delay cost to route message between the two nodes that is twice the delay cost of the underlying network
c) the underlying network has a delay cost to route message between the two nodes that is twice the delay cost of the overlay network
b) the overlay network has a delay cost to route message between the two nodes that is twice the delay cost of the underlying network
In flooding-based multicasting, which of these statements is/are correct:
a) Message routing in an unstructured network has the same cost as routing in a structured network with equal number of nodes
b) The number of messages routed always depend on the number of edges (paths) in the overlay network
c) It is less expensive to route messages in a fully-connected graph compared to a tree topology of equal number of nodes
d) Messages will be routed through every connected node in the network
b) The number of messages routed always depend on the number of edges (paths) in the overlay network
d) Messages will be routed through every connected node in the network
An application-layer overlay network has 10000 replicated nodes, about 99% of these nodes have received update. You have developed an algorithm that keeps track of this statistics in the network. Which operation would be best to prioritize to get the remaining 1% nodes updated?
a) Push
b) Pull
c) Push-Pull
c) Push-Pull
Asynchronous RPC can be implemented by using the concept of:
a) Not possible because RPC always provide synchronous communication
b) Callback that triggers a function at the client’s end
c) Multi-threading
b) Callback that triggers a function at the client’s end
c) Multi-threading
A key reason to use probabilistic flooding model in flood-based multicasting is to:
a) Reduce the number of messages in the network
b) Create a structured overlay network
c) Increase the number of messages to ensure reliability
a) Reduce the number of messages in the network
Some approaches for exchanging updates/messages using anti-entropy propagation model are:
a) Pull (Node P, pulls new updates from node Q)
b) Push-Pull (Nodes P and Q send updates to each other)
c) Push (Node P only pushes its own updates to node Q)
a) Pull (Node P, pulls new updates from node Q)
b) Push-Pull (Nodes P and Q send updates to each other)
c) Push (Node P only pushes its own updates to node Q)
An unstructured p2p overlay network of 500 nodes has a probability (p = 0.6) that two nodes are connected by an edge. What is the estimated number of messages that can be routed in this network?
a) 75000
b) 500
c) 300
d) 125000
a) 75000
Consider a tree and a fully connected overlay network with 10 nodes each. What is the total number of messages that will be routed across both topologies using flooding-based multicasting
a) 10 messages in the tree and 50 messages in the fully-connected network
b) 50 messages in the tree and 10 messages in the fully-connected network
c) 9 messages in the tree and 100 messaged in the fully-connected network
d) 9 messages in the tree and 45 messages in the fully-connected network
d) 9 messages in the tree and 45 messages in the fully-connected network
Tree Topology
In a tree topology with 10 nodes:
- Flooding starts from one node and each node forwards the message to all its children (if any).
*In a tree with 10 nodes, there are 9 edges (because a tree with n nodes always has n−1 edges).
Hence, when a message is flooded in a tree, it will travel through each edge exactly once.
So, in the tree topology, the total number of messages will be 9.
Fully Connected Network
Node 1 sends to 9 nodes.
Then each subsequent node has 1 less unique node to send to:
9+8+7+…+1=9×10/2= 45
