unit 6 protocols and ports

Question 1

is standard set of rules that allow electronic devices
to communicate with each other over the network
* Dictate how to format, transmit and receive data so computer
network devices can communicate regardless of differences in
underlying infrastructures, designs or standards
* Can be thought of as a spoken language

Answer 1

protocol

Question 2

Used by majority of Internet
 Combination of protocols which encompasses number of different
protocols for different purpose and need
 Has own reference model; contains less layers than OSI model
 Can be implemented on almost all underlying technologies
 Transport and Internet layers correspond to same peer layers
 All three top layers of OSI Model are compressed together in single
Application layer of TCP/IP Model

Answer 2

TCP/IP Protocol Suite

Question 3

Where applications requiring network
communications live
Examples include email clients and web browsers
Software you generate for end application will
typically interact with some of these applications
Most commonly used TCP/IP application is HTTP
used for surfing internet

Answer 3

 Application Layer (layer 5)
TCP/IP Model

Question 4

Creates virtual TCP or UDP connections between
applications running on different hosts
Uses TCP for reliable connections and UDP for
fast connections
Sends and receives data to and from
applications running on host
Assigns port numbers to protocols running in
applications on host

Answer 4

 Transport Layer (Layer 4)
TCP/IP Model

Question 5

Adds TCP or UDP header to messages received
from applications detailing source and
destination port numbers

Answer 5

Transport Layer

Question 6

Some applications (Telnet, SMTP, and HTTP)
require TCP as transport protocol while others
use UDP

Answer 6

Transport layer

Question 7

Uses Network layer to access TCP/IP network

Answer 7

Transport layer

Question 8

Uses TCP for reliable connections and UDP for
fast connections

Answer 8

Transport layer

Question 9

what layer is the transport layer of the TCP/IP layer

Answer 9

Layer 4

Question 10

When transmitting data, adds header containing
source and destination IP addresses to data
received from Transport layer

Answer 10

Network Layer (Layer 3)

Question 11

Responsible for creating the packets that move
across network

Answer 11

Network layer

Question 12

Packet created forwarded to the MAC or Data Link
layer

Answer 12

Network Layer

Question 13

When receiving data, used to determine if packet
received by the host contains the host’s IP address
If it does, data is forwarded up to Transport layer

Answer 13

 Network Layer

Question 14

MAC controls physical transmission media; upper
layer software not aware of or affected by
physical interface

Answer 14

 Data Link Layer (Layer 2)

Question 15

Responsible for creating frames that move across
network

Answer 15

Data Link Layer

Question 16

Uses Media Access Controller (MAC) to generate
frames that will be transmitted

Answer 16

Data link layer

Question 17

Encodes and decodes found in a frame
Sends and receives signals on physical wire or
antenna to transmit/receive the bits found in
frames

Answer 17

 Physical Layer (Layer 1)

Question 18

Defines how data is formatted, transmitted, and what actions
web servers and browsers should take in response to various
commands

Answer 18

Hyper Text Transmission Protocol
(HTTP)

Question 19

Operates in the Application, Presentation, and Session layers
of OSI Reference Model

Answer 19

Hyper Text Transmission Protocol
(HTTP)

Question 20

Allows you to browse websites using a web browser

Answer 20

Hyper Text Transmission Protocol
(HTTP)

Question 21

Divides files into several segments and assigns reference
number to each one

Answer 21

File Transfer Protocol (FTP)

Question 22

Most basic way of sending and receiving files over internet

Answer 22

File Transfer Protocol (FTP)

Question 23

Method of transferring data files from one computer to
another over network

Answer 23

File Transfer Protocol (FTP)

Question 24

Used to transfer e-mail messages and attachments

Answer 24

Simple Mail Transfer Protocol
(SMTP)

Question 25

Built into e-mail client and e-mail server software

Question 26

Operates in Application, Presentation, and Session layer of OSI
reference model

Answer 26

Simple Mail Transfer Protocol
(SMTP)

Question 27

Operates at Network layer of OSI model.

Answer 27

Internet Protocol (IP)

Question 28

Basis for all addressing on TCP/IP networks
* Connectionless-oriented network layer protocol
* For devices to communicate on the network, must be
configured with valid IP address

Answer 28

Internet Protocols IP

Question 28

Set of protocols created to permit remote monitoring and
management of devices and hosts
* Operates in Application, Presentation, and Session layers of
OSI reference model
* Examples are packet sniffers, which monitor and log individual
packets that travel along network
 Packet sniffers watch for specific types of problems and provide
analysis of packet

Answer 28

Simple Network Management
Protocol (SNMP)

Question 29

Provides friendly name to IP address on internet
* Lets you use name rather than numbers to refer to host
computers
* For example, when you type “www.af.mil” into Web browser,
DNS server resolves www.af.mil into IP address 131.77.61.125

Answer 29

Domain Name System (DNS)

Question 30

Uses broadcast UDP data packets to exchange routing
information
* Cisco software sends routing information updates every 30
seconds, which is termed as advertising
* If device does not receive update from another device for 180
seconds or more, receiving device marks routes served by
non-updating device as unusable

Answer 30

Routing Information Protocol (RIP)

Question 31

Protocol for automatically assigning dynamic IP addresses to
devices on network.

Answer 31

Dynamic Host Configuration
Protocol (DHCP)

Question 32

allows device to have different IP address
every time it connects to network

Answer 32

Dynamic Host Configuration
Protocol (DHCP)

Question 33

simplifies network management of IP
addresses and configuration management because software
keeps track of IP addresses rather than administrator

Answer 33

Dynamic Host Configuration
Protocol (DHCP)

Question 34

Used for “resolving” (converting) network layer (IP) address
into link layer address (MAC)

Answer 34

Address Resolution Protocol (ARP

Question 35

Operates at Network layer of OSI Reference model
Stays within boundaries of single network; never routed
across internetwork nodes

Answer 35

Address Resolution Protocol (ARP)

Question 36

Virtual path to send and receive data from computers
* Used to communicate between two different applications
* Part of TCP/IP networking
* Computers and routers automatically manage network traffic
traveling via virtual ports
* Network firewalls provide control over traffic on virtual ports
for security

Answer 36

Ports

Question 37

well known Port range

Answer 37

0-1023

Question 38

what are the 3 ranges of ports

Answer 38

well known, registered, and dynamic private or ephemeral ports

Question 39

Ports range from 49152–65535
 Cannot be registered with IANA
 Used for custom or temporary purposes and for automatic
allocation of ephemeral (temporary) ports
 Assigned as needed then released when the service is finished
* Port Status
 Open
 Closed

Answer 39

dynamic private or ephemeral ports

Question 40

what are the two ports status

Answer 40

open closed