8 - 1.1: TCP/IP Networking

Question 1

TCP/IP

Answer 1

A set of networking protocols, stands for Transmission Control Protocol / Internet Protocol

Question 2

Main roles of IP

Answer 2

Providing an addressing scheme to uniquely identify computers on a network and deliver information

Question 3

Packets

Answer 3

Chunks of information sent over networks

Question 4

IP is a ______ layer protocol

Answer 4

Network

Question 5

Two main transport layer protocols

Answer 5

Transmission Control Protocol (TCP) and User Datagram Protocol (UDP)

Question 6

TCP is defined as

Answer 6

A connection-oriented protocol, guarantees delivery through acknowledgment

Question 7

Three-way handshake

Answer 7

A TCP process for creating a connection before data is transmitted..

Question 8

TCP packet flags role

Answer 8

Special flags that identify packets used in the handshaking process

Question 9

TCP packet flag names

Answer 9

SYN, FIN, ACK

Question 10

SYN flags

Answer 10

open a connection

Question 11

FIN flags

Answer 11

close a connection

Question 12

ACK flags

Answer 12

acknowledge a SYN or FIN

Question 13

Three steps of handshake

Answer 13

1) originating system sends SYN 2) destination receives, sends a SYN + ACK packet set 3) originating system sends an ACK packet

Question 14

UDP is defined as

Answer 14

Lightweight connectionless protocol that doesn’t send acknowledgments or guarantee delivery

Question 15

OSI model

Answer 15

Open Systems Interconnection model

Question 16

OSI layers

Answer 16

1) physical 2) data link 3) network 4) transport 5) session 6) presentation 7) application

Question 17

Physical layer

Answer 17

Sending bits with wires, radio waves, fiber optics, etc.

Question 18

Data link layer

Answer 18

Transfers data between nodes on the same physical network

Question 19

Network layer

Answer 19

expands networks to different nodes

Question 20

Transport layer

Answer 20

Creates connections between systems and reliably transfers data

Question 21

IP works at the ______ layer

Answer 21

Network

Question 22

TCP and UDP work at the _____ layer

Answer 22

Transport

Question 23

Session layer

Answer 23

Manages exchange of communication between systems

Question 24

Presentation layer

Answer 24

translates data for network transmission, describes how to represent a character in terms of bits, performs cryptography

Question 25

Application layer

Answer 25

Determines how users interact with data using software

Question 26

IP addresses

Answer 26

Uniquely identifying numbers for internet locations

Question 27

Dotted quad notation

Answer 27

Four numbers, ranging between 0 - 255, separated by dots

Question 28

Why 255?

Answer 28

Each number in the IP quad is represented by eight binary bits. 2 to the eight is 256, but we start at 0 so 255

Question 29

NAT

Answer 29

Network Address Translation: there are only so many IP addresses that can possibly be made, so your home/org uses repeated one other places also do. Routers translate those private IPs into publicly facing ones

Question 30

IP address portions

Answer 30

Network portion and host address

Question 31

Network portion

Answer 31

Identifies the network that a system is connected to

Question 32

Host address

Answer 32

Uniquely identifies a system/device on that network

Question 33

Subnetting

Answer 33

Subdividing IP addresses beyond the normal 4 numbers

Question 34

IP addresses in network communication

Answer 34

Source address and destination address

Question 35

Source address

Answer 35

Indicates the system sending information

Question 36

Destination address

Answer 36

Destination address indicates system receiving information

Question 37

IPv4

Answer 37

32-bits, four numbers

Question 38

IPv6

Answer 38

128 bits, using eight groups of four hexadecimal digits

Question 39

IP address assignment

Answer 39

Static or Dynamic Host Configuration Protocol

Question 40

Static address assignment

Answer 40

Manually specify IP addresses, requires fitting within the network range

Question 41

Dynamic Host Configuration Protocol

Answer 41

Configures a pool of IP addresses, then automatically assigns from that pool as systems join

Question 42

Domain Name System / servers

Answer 42

Translates the names of web locations into addresses computers use, operating over UDP port 53

Question 43

DNS Resolution

Answer 43

1) Enter domain name in browser 2) computer sends DNS query to local DNS server 3) DNS server responds with an IP address 4) computer contacts server at that address

Question 44

DNS is a ____ system

Answer 44

Hierarchical. If one local DNS server doesn’t know the answer, it will contact others that do

Question 45

DNS poisoning

Answer 45

Inserting false DNS records to redirect users to malicious sites or locations

Question 46

DNSSEC

Answer 46

Adds an extra signature to DNS records for verification

Question 47

Network ports

Answer 47

A sub-address within IP address locations to specify applications

Question 48

Network port numbers

Answer 48

16-bit binary numbers, ranging between 216 or 65,536 possible values. Starting at 0, that makes the maximum 65,535

Question 49

Network port ranges

Answer 49

0 to 1,023: Well-known ports
1024 to 49,151: Registered ports
Above 49,151: Dynamic ports

Question 50

Well-known ports

Answer 50

Reserved for common applications issued by internet authorities; web servers, email servers, etc.

Question 51

Registered ports

Answer 51

Vendors may reserve these for their applications, such as Microsoft’s SQL databases on 1433 and Oracle’s on 1521

Question 52

Dynamic ports

Answer 52

Reserved for use on a temporary basis

Question 53

Internet Control Message Protocol

Answer 53

The “housekeeping” protocol of the network

Question 54

Ping command

Answer 54

Sending an “are you there,” echo command to another system

Question 55

Traceroute

Answer 55

More detailed troubleshooting, including status and messages, network path taken, and performance