Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Distributed Computing > 1 - Intro > Flashcards

1 - Intro Flashcards

1
Q

Define a distributed system

A

A collection of independent computers that appear as a single coherent system

Multiple processors that do not share memory but cooperate using messages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 4 design goals of distributed computing?

A
  • Resource Sharing
  • Open and modular
  • Transparency
  • Scalability
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Resource sharing benefits

A

Saves money
Enables communication and collaboration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Open/Modular is easy to…

A

Easy to:
- Use
- Extend
- Combine with others
- Integrate into other systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Is open/modular monolithic?

A

No, as that would imply one block.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define transparency in the context of computing

A

Removing obstacles to easier understanding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The 7 types of transparency

A

Access
Location
Migration
Relocation
Replication
Concurrency
Failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define Access transparency

A

Hide differences in representation and how it is accessed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What separates Location, Migration and Relocation transparency?

A

Location: Hide where it is located
Migration: Hide that a resource may move
Relocation: Hide that a resource may move WHILE IN USE`

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The 3 types of scalability are:

A

By Size
Geographical
Administrative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define scalability by size

A

More users/resources without noticeable performance loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define geographical scaling

A

Distributed over various regions but communication delays hardly noticeable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define administrative scaling

A

Manageable over different domains/organisations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Decentralised Systems: What level of information does each machine have?

A

No machine has complete info and each decides based on local info

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Decentralised Systems: Fault Tolerant?

A

Yes. Failure of one machine does not ruin the algorithm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Decentralised Systems: Global CLock?

A

THere is no implicit assumption that a global clock exists

17
Q

What systems aren’t good with synchronous communication? What is sync Comms bound by?

A

Not good for large systems
Speed of communication is bound by speed of light

18
Q

3 scaling techniques (not scaling types)

A

Distribution
Caching
Replication

19
Q

What are potential false assumptions made when developing distributed systems?

A
  • Network is reliable, secure & homogeneous
  • Topology is unchanging
  • Zero latency
  • Infinite bandwidth
  • Zero transport cost
  • Only one admin
20
Q

Time models

A

Asynchronous (unknown process speed, unknown comms speed)
Synchronous (Assumed equal process speed, communication step fixed time)

21
Q

Define Security Model

A

Designing a system to be secured against one or more threats

22
Q

Types of distributed systems

A

Computing - Cluster, grid and cloud
Information - Transaction based systems, enterprise app integration
Pervasive - Body area networks, sensor networks

23
Q

Cluster Computer

A

PCs with a high speed network

Used for parallel programming

Leader distributes tasks to nodes

24
Q

Grid Computing: Definition

A

Grid companies form virtual orgs that share resources

25
Q

Grid Computing: Advantages

A

Easy access
Improved sharing and utilisation of resources

26
Q

Grid Computing: Problems

A

Heterogeneity of hardware, management, security strategies

27
Q

Grid Computing: Layers

A

Fabric
Connectivity
Resource
Collective
Applications

28
Q

Cloud Computing: Advantages

A

Easy access
IT Outsourcing

29
Q

Cloud Computing: Disadvantages

A

Latency, bandwidth, security.
Trust in provider is required

30
Q

TPS: Define a transaction

A

Sequence of operations that are treated as a unit

31
Q

TPS: ACID Properties

A

Atomic
Consistent
Isolated
Durable

32
Q

ACID: Atomic

A

Indivisible. All operations executed or none

33
Q

ACID: Consistent

A

Does not violate system invariants and goes to another valid state

34
Q

ACID: Isolated

A

Concurrent transactions do not interfere with each other

35
Q

ACID: Durable

A

Changes are permanent

36
Q

TPS: What does a Transaction Processing Monitor do?

A

Ensures that all independent requests have been made successfully before replying to the client

37
Q

What is a sensor network?

A

Used to monitor an environment, such as machines in a factory

Distributed Computing (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions