Distributed Information Systems
1DT066 Distributed Information Systems Homework 2 1) This is a g eneral question on distributed systems. a) With examples describe Access, Location and Migration transparency in a distributed system. b) With…
1DT066 Distributed Information Systems
This is a g
on distributed systems.
With examples describe Access, Location and Migration transparency in a
s describe what Middleware is.
cribe the client server model?
What is redundancy and why is it used in a distributed system.
This is a question on remote procedure call.
What are Client and Server Stubs and how are they used in re
When passing data values betwe
ifferent machines with dif
operating systems what proble
ms have to be solved?
When calling a remote procedure or method where a reference parameter
is passed, what problems have to be solved and how are they solved?
Consider the events of proces
ses P1, P2 and P3 in the following figure:
L(e): denotes the Lamport timestamp of event e.
V(e): denotes the Vector timestamp of event e.
Write down the Lamport timestamps
in the above figure
Write down the Vector timestamps
in the above figure
an the order of Lamport timestamps infer the order of events? In other
words, if L(e) < L(e’), can we infer that e
e’ in Lamport timestamps?
Similarly, if V(e) < V(e’), can we infer that e
e’ in Vector timestamps?
Consider a server provides the
operations for its clients to a
number of objects
M1, M2, … , Mn
returns the value of object
There are two transactions A and B defined as follows:
x=Read(j); y=Read(i); Write(j,4),
x=Read(k); Write(i,5); y=Read(j); Write(k,6).
Give three serially equivalent interleavings of the transactions A and B.
What duties does the ‘link layer’ have in an standard network stack?
Describe at least 3 points.
ering Medium Access Control, describe an advantage and a
of “Channel Partitioning” approaches compared to “Random
f nodes listen to the medium to
ensure it is free before transmitting data, how can collisions still occur?
computer program wants to load a file from the hard disk into memory.
Describe at least 4 steps that occur during this process.
b) The file has been loaded to memory.
At some point in its operation, the
program wants to have the first byte from
the file in its CPU
. Describe at least
4 operations that will be performed before the byte can be
What is the difference between two
phase locking and two
phase locking prevent inconsistent analysi
Which transactional property is enforced by distributed commit
protocols? Explain briefly.
Please submit your personal answers electronically to
y 15:00 Dec 9