Pen Testing Midterm

Question 1

cloud computing’s meaning

Answer 1

a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction.

Question 2

remote resources

Answer 2

a device that is available for shared use on internet.

Question 3

IoT

Answer 3

a device that connects to the internet and allows a user to connect to it.

Question 4

on-demand provisioning (focus)

Answer 4

Cloud provisioning is the allocation of a cloud provider’s resources and services to a customer.

Question 5

HPC

Answer 5

high performance computing- capability

Question 6

high throughput computing

Answer 6

capacity

Question 7

calculate the speed-up factor of a parallel system, in two ways:

Answer 7

○ Amdahl’s Law (time) : Total Execution time: aT+(1-a)T/n
T is the time taken on a single server/processor/core
A is “sequential bottleneck”
N is the number of servers/processors/cores
S=T/[aT+(1-a)T/n]=1/a[a+(1-a)/n]

○ Gustafson''s Law (tasks)
Assume a given time perio
W is the work done on a single server/processor/core
Speedup factor
S'=W'/W=[aW+(1-a)nW]/W =a+(1-a)n

Question 8

• calculate the availability of a system, or a cluster

Answer 8

○ basic formula for one system: MTTF / ( MTTF + MTTR )
○ MTTF: mean time to failure
○ MTTR: mean time to repair

evaluate the cluster availability based on individual system: combination/probability

Question 9

what is the Internet?

Answer 9

Global system of interconnected computer network that use TCP/IP to link devices worldwide

Question 10

what is the WWW(world wide web)?

Answer 10

○ An information space where documents and other web resources are identified by URLs, interlinked and can be accessed via the internet

Question 11

HTTP protocol

Answer 11

§ A stateless protocol
structure of a request and a response
methods:
GET: transfer a current representation of the target resource
POST: perform resource-specific processing on the request payload
PUT: replace all current representations of the target resource with the request payload
Its position at the layered network model- application layer

Question 12

five virtualization levels:

Answer 12

ISA level: an instruction set architecture (ISA) is the interface between the computer’s software and hardware and also can be viewed as the programmer’s view of the machine

hardward level- use of computing hardware in an envrionment separate from the actual existence of the hardware

OS level- os paradigm in which the kernel allows the existence of multiple isolated user space instances

library level- user level. Can create execution environments.
application level- software technology that encapsulates computer programs from the underlying operations system on which they are executed.

Question 13

What is a hypervisor

Answer 13

A process that seperates a computers OS and applications from the underlying physical hardware.

Question 14

VMM

Answer 14

Virtual Machine Manager

Question 15

What about type I and type II?

Answer 15

Type 1: Bare metal

Type 2: runs on top of an OS

Question 16

What type is VMware ESXi?

Answer 16

Type 1

Question 17

full virtualization vs para-virtualization, and hardward-assisted virtualziation

Answer 17

○ Full virtualization: guests will issue a hardware calls
○ Para-virtualization: guests will directly communicate with the host
○ Hardware-assisted virtualization: use of a computers physical components to support the software that creates and manages VM

Question 18

hardware-level

Answer 18

virtual box

Question 19

OS-level

Answer 19

docker

Question 20

Popek and Goldberg virtualization requirements:

Answer 20

Popek and Goldberg virtualization requirements:

Question 21

VMs vs containers

Answer 21

VM- under a VM environent, each workload needs a complete OS

Container- multiple workloads can run with 1 OS

Question 22

OpenVZ vs Dockers - the main differences

Answer 22

Docker is single application focus and OpenVZ provides the entire OS in a container. Open VZ has support for live migration.
basic docker commands

Question 23

basic docker commands

Answer 23

docker run
docker pull
docker push
docker container start
docker ps
docker image ls
docker help

Question 24

what does Docker Swarm do?

Answer 24

○ A group of either physical or virtual machines that are running the docker application and that have been configured to join together in a cluster
○ Docker Compose- is a tool for defining and running multi-container docker applications
○ Docker Machine- a tool for provisioning and managing your dockerized hosts
Docker Compose file- YAML file to configure your applications services

Question 25

what is VM management?

Answer 25

○ Used to configure, manage and transform traditional datacenters and hep provide a unifided management experience.

Question 26

what is container orchestration?

Answer 26

All about managing the lifecyles of containers, especially in large, dynamic environments.

Question 27

kubernetes concepts

Answer 27

○ Pods Are smallest deployable units of computing that can be created and managed in Kubernetes ○ Nodes A worker machine in Kubernetes. ○ Services An abstraction which defines a logistical set of pods and a policy by which to access them. Deployments Ensures that only a certain number of pods are down while they are being updated.

Question 28

• basic kubernetes commands

Answer 28

kubectl create -f deployment.yaml | kubectl get pods