1.3 Protocols And Packet Analysis

Question 1

An agreement between Network entities, such as hosts and servers, for how they will communicate.

Answer 1

Network protocol

Question 2

Where each protocol layer receives a service from the layer below it and provides a service to the layer above it.

Answer 2

Protocol stack

Question 3

Protocol stack that divides network communications into seven layers.

Answer 3

OSI model

Question 4

Acronym for the seven layers of the OSI protocol stack

Answer 4

All people seem to need data processing.

People Don’t Need Those Stupid Packets Anyways.

Physical, data link, network, transport, session, presentation, application.

Question 5

Blocks of data that describe work that was done at a corresponding layer.

Answer 5

Headers

Question 6

An attacker forges the IP address in the IP header to make a communication appear to originate from an IP address that it isn’t.

Answer 6

IP address spoofing

Question 7

the process of moving down a protocol stack with each layer doing work and leveraging the addition of a header to describe said work

Answer 7

Encapsulation

Question 8

the process of moving up a protocol stack with each layer doing work combined with the reading and removing of headers.

Answer 8

Decapsulation

Question 9

Whenever we discuss network communications and the corresponding layers we must always reference this model

Answer 9

OSI model

Question 10

Mnemonic for the TCP/IP model

Answer 10

Never Interrupt The Aardvark

Network, internet, transport, application.

Question 11

The core routing protocol of the internet. Handles the transmission of packets between Network endpoints. It’s job is to determine the best route for a communication between two endpoints on two different networks.

Answer 11

IP - internet protocol

Question 12

Allows for IPv6 communication between two IPv6 endpoints over IPv4 without the routing systems requiring any knowledge of ipv6.

Answer 12

IPv6 over IPv4 (tunneling)

Question 13

Allows ipv4 addresses to be translated from their current form into IPv6 compatible addresses.

Answer 13

Ipv4 over IPv6 translation

Question 14

This layer of the OSI model is responsible for determining the routes to be taken between two network devices.

Answer 14

Network layer, layer three

Question 15

Protocol whose primary purpose is to report error conditions.

Answer 15

ICMP - internet control message protocol

Question 16

A session oriented communication protocol, operating at the transport layer of the OSI model.

Answer 16

TCP - transmission control protocol

Question 17

Layer 3 protocol that establishes a session between hosts prior to data exchange.

Answer 17

TCP - transmission control protocol

Question 18

A use of TCP that allows for the communicating hosts to exchange messages to affect how much data can be transmitted at any given time.

Answer 18

Flow control

Question 19

Layer 3 OSI protocol that can allow you to map a computer, to know that it is alive and a port is available.

Answer 19

ICMP - internet control message protocol

Question 20

TCP flag that is used to indicate that the computing systems are synchronizing their sequence numbers.

Answer 20

SYN - synchronize

Question 21

TCP flag that is used to acknowledge the next sequence number a computer expects to receive.

Answer 21

ACK - acknowledge

Question 22

TCP flag that is an integer that will assist in the tracking of data that is being communicated in either direction.

Answer 22

ISN - initial sequence number

Question 23

These numbers indicate where applications on a computer system are expecting to send and receive their network communications.

Answer 23

Port numbers

Question 24

Port numbers in the range of 1024 to 65535 for client use.

Answer 24

Ephemeral port numbers

Question 25

Port numbers in the range of 1 to 1023 for the use of servers.

Answer 25

Privileged port numbers