Networking

Question 1

Default Gateway

Answer 1

IPv4 address of the router that is connected to other subnets (or the external internet, if necessary)

Question 2

Special / Reserved IP Addresses: a way for a machine to reference itself

Answer 2

Loopback Address or “home”

Range: 127.0.0.1 - 127.255.255.254

Question 3

Special / Reserved IP Addresses: when packets are sent, they are sent to every device on the subnet

Answer 3

Broadcast Address - last address in a subnet is typically reserved for the broadcast address

Question 4

Special / Reserved IP Addresses: second number in a subnet (the first number, “.0”, is reserved for the network name)

Answer 4

Router Address - “.1”

Question 5

Special / Reserved IP Addresses: 240.0.0.0 - 255.255.255.255

Answer 5

Reserved for future use and research; “Experimental” - Class E

Question 6

Special / Reserved IP Addresses: 224.0.0.0 - 239.255.255.255

Answer 6

Multicast addresses; Class D

Question 7

Special / Reserved IP Addresses: 192.0.0.0 - 223.255.255.255

Answer 7

Class C

Question 8

Special / Reserved IP Addresses: 128.0.0.0. - 191.255.255.255

Answer 8

Class B

Question 9

Special / Reserved IP Addresses: 1.0.0.0 - 127.255.255.255

Answer 9

Class A; 127.0.0.1 to 127.255.255.255 reserved for use as loopback addresses

Question 10

Transmission Control Protocol (TCP)

Answer 10

Provides connection-oriented service at the transport layer, with guaranteed delivery; establishes a session; can retransmit dropped packets

Question 11

User Datagram Protocol (UDP)

Answer 11

Provides connectionless service at the transport layer

Question 12

Hypertext Transfer Protocol (HTTP)

Answer 12

Operates at the application layer

Question 13

Internet Protocol (IP)

Answer 13

Connectionless network layer protocol

Question 14

65,535 possible ports (131, 070 total ports)

Answer 14

TCP & UDP

Question 15

Well-Known Ports: 1 - 1023

Answer 15

Typically used at end of server where well-known services are running (not typically used when selecting ports to start communication from)

Question 16

Registered Ports: 1024 - 49151

Answer 16

Vendors can register these ports

Question 17

Ephemeral (temporary) Ports: 49152 - 65535

Answer 17

Picked randomly by client machines during the 3-way handshake

Question 18

PORT: 21, 21 (TCP)

Answer 18

File Transfer Protocol (FTP)

Question 19

PORT: 22 (TCP)

Answer 19

Secure Shell (SSH) - an encrypted remote command line interface

Question 20

PORT: 23 (TCP)

Answer 20

Telenet - an UNencrypted remote command line interface

Question 21

PORT: 25 (TCP)

Answer 21

Simple Mail Transfer Protocol (SMTP) - UNencrypted agent to send / receive email

Question 22

PORT: 80 (TCP)

Answer 22

Hypertext Transfer Protocol (HTYTP) - UNencrypted data transfer for web pages

Question 23

PORT: 443 (TCP)

Answer 23

HTTPS - HTTP Secure - encrypted data transfer for web pages

Question 24

PORT: 3389 (TCP)

Answer 24

Remote Desktop Protocol (RDP) - an encrypted remote graphical user interface

Question 25

PORT: 53 (UDP)

Answer 25

Domain Name Server (DNS) - resolve domain names to IP addresses; unencrypted

Question 26

PORT: 67, 68 (UDP)

Answer 26

Dynamic Host Configuration Protocol (DHCP) - automatically handles network configuration and IP address leasing to devices connecting to a network; unencrypted

Question 27

PORT: 123 (UDP)

Answer 27

Network Time Protocol (NTP) - clock synchronization between network devices; unencrypted

Question 28

PORT: 161, 162 (UDP)

Answer 28

Simple Network Management Protocol (SNMP) - protocol to manage, modify, and collect information on network devices; Version 3 is encrypted

Question 29

ICMP

Answer 29

Internet Message Control Protocol - OSI Layer 3 (Network) - communicate information about network connectivity issues back to the source of the compromised transmission; packets send to determine if target host is connected to the network or not

Question 30

Ping

Answer 30

a way to detect is a target host is on or offline

Question 31

traceroute

Answer 31

a way to enumerate all the routers in between the client and the target host; increments time-to-live, plus one