1
2
3
4
5
6
7
8
100
Provide 2 examples of a distributed system?
The internet
Telecommunications networks
Cloud computing
TOR networks
100
Name the layers which the OSI model has which the TCP/IP model does not have
Session
Presentation
100
Explain how IaaS works
The cloud provider supplies a technical infrastructure which users can access via public or private networks.
100
What is a process
A process a program in execution
100
What is a thread
A thread is the basic unit to which the operating system allocates processor time
100
Another name for symmetric cryptosystems
Symmetric cryptosystems are also referred to as secret-key or shared-key systems
100
Explain what the letters in the CIA Triad stand for
•Confidentiality deals with keeping resources and data hidden from, or inaccessible to, unauthorized individuals.
•Integrity deals with the trustworthiness of the data or the resources.
•Availability is about having access to the data or computing services.
100
There are two primary reasons for replicating data, name them
Reliability
performance
200
Define what a distributed system is
A distributed system is a computing environment in which various components are spread across multiple computers (or other computing devices) on a network.
200
Which sublayer of the data link layer performs data link functions that depend upon the type of medium?
media access control sublayer
200
All cloud computing applications suffer from the inherent _______ that is intrinsic in their WAN connectivity.
latency
200
Transmission data rate is decided by which layer
physical layer
200
Scaling transparency hides
system expansion
200
the load of data processing and transformation is put on the server side, and the client has a light implementation that is mostly concerned with retrieving and returning the data it is being asked for, with no considerable further processing
What is this
Thin client
200
Define the term fault tolerance
Ability of a system to continue functioning in the event of a partial failure.
200
Mention two features of a DFS
HA
Security
High reliability
Data integrity
Scalability
Performance
Ease of use
300
Give an example of a layered architecture
OSI
300
What is a Remote Procedural Call?
a communication technology that is used by one program to make a request to another program for utilizing its service on a network without even knowing the network's details
300
What function does the session layer provide
It provides dialog control, to keep track of which party is currently talking, and it provides synchronization facilities.
300
Define what an absolute path is
An absolute path is defined as specifying the location of a file or directory from the root directory(/).
300
List 3 services which digital signatures provide
Message authentication
Data integrity
non repudiation
300
Which layer is responsible for process to process delivery in a general network model?
Transport layer
300
Explain how a client server architecture works
The server is where all the work processes are, while the client is where the user interacts with the service and other resources (remote server).
The client can then request from the server, and the server will respond accordingly
300
The benefits of a multi-threaded programming can be broken down into 4 categories, name them
Responsiveness
Resource sharing
Economy
Scalability
400
Define Portability
the extent an application developed for a distributed system A can be executed, without modification, on a different distributed system B that implements the same interfaces as A
400
Define extensibility
the extent an open distributed system should be easily configured out of different components
400
In TCP IP Model, when data is sent from device A to device B, the 5th layer to receive data at B is
Application layer
400
According to (Kopetz and Verissimo, 1993) dependability is a term that covers a number of useful requirements for distributed systems, list them?
•1. Availability
•2. Reliability
•3. Safety
•4. Maintainability
400
List the major components of the Unix operating System architecture
Kernel
Shell
Commands and Utilities
User Applications
400
Explain the deference between user level threads and kernal level threads
•User Level Threads − User managed threads. Supported above the kernel and managed without kernel support
•Kernel Level Threads − Operating System managed threads acting on kernel. Supported and managed directly by the operating system.
400
Explain how the no leader architecture works
Every server in this architecture can receive writes and function as a replica model.
400
Explain how the single leader architecture works
one server accepts client writes and replicas pull data from it
500
Scalability is generally considered concerning hardware and software.
Explain what hardware scalability refers to
In hardware, scalability refers to the ability to change workloads by altering hardware resources such as processors, memory, and hard disc space.
500
Define what an intermittent fault is
faults that occur, then vanishes of its own accord, then reappears.
500
Explain how semi synchronous replication works
•In Semi-synchronous Replication, once the Master node updates its own copy of the data, it synchronously replicates the data to a subset of Replicas and asynchronously to others.
500
Fault Tolerance is needed in order to provide 3 main feature to distributed systems, name them
Reliability
Availability
Security
500
List the phases of fault tolerance
•1)Fault Detection
•2)Fault Diagnosis
•3)Evidence Generation
•4)Assessment
•5)Recovery
500
Give an example of a hard fault and a soft fault
Hard fault - failed component, power fail, fire, flood, design error (usually software), sabotage
Soft fault- specification error, design error, coding error, e.g. use on un-initialized variables, integration error
500
explain how one way functions work
it is computationally infeasible to find the input that corresponds to a known output
500
Provide 4 benefits of multi-threaded processes
multitasking
600
Explain vertical scalability with an example
Upgrading a server
600
Explain how Raid 1 works
Data are stored twice by writing them to both the data drive (or set of data drives) and a mirror drive (or set of drives). If a drive fails, the controller uses either the data drive or the mirror drive for data recovery and continuous operation
600
Explain how RAID 0 works
RAID 0 (disk striping) is the process of dividing a body of data into blocks and spreading the data blocks across multiple storage devices, such as hard disks or solid-state drives (SSDs), in a redundant array of independent disks (RAID) group.
600
Explain the difference between grid computing and cluster computing
Cluster computing: In cluster computing you have a collection of connected computers that work together as a unit to perform operations together, functioning in a single system.
•Grid computing: In grid computing, the subgroup consists of distributed systems, which are often set up as a network of computer systems, each system can belong to a different administrative domain and can differ greatly in terms of hardware, software, and implementation network technology.
600
Mention the false assumptions that everyone makes when developing a distributed application for the first time
•1. The network is reliable.
•2. The network is secure.
•3. The network is homogeneous.
•4. The topology does not change
•5. Latency is zero.
•6. Bandwidth is infinite.
•7. Transport cost is zero.
•8. There is one administrator.
600
Explain how asymmetric cryptosystems work
•In an asymmetric cryptosystem, the keys for encryption and decryption are different, but together form a unique pair.
•One of the keys in an asymmetric cryptosystem is kept private; the other is made public.
600
"Shinobi are human too. Maybe it’s impossible to become an emotionless tool. I’ve lost."
Zabuza (Naruto)
600
A good cryptography algorithm (cryptosystem) has three properties, what are they
Ciphertext should look random
There is no way to extract the original plaintext or key from the ciphertext
Keys should be long enough to make a brute-force attack not feasible.