Network Fundamentals

Question 1

OSI Model

Answer 1

Physical, Data, Network, Transport, Session, Presentation, Applications

Question 2

Physical Layer

Answer 2

defines how data is sent through network (hubs)

Question 3

Data Layer

Answer 3

tranfer data between two nodes (switches, MAC, NIC)

Question 4

Network layer

Answer 4

allows hosts to send packets between networks (ping, tracert) Routers work here

Question 5

Transport

Answer 5

handles data transfer between end systems, how much data sends, rates, destinations (Flow control, reliability)

Question 6

Session

Answer 6

creates and maintains session (IP, logical addresses, routers)

Question 7

Presentation

Answer 7

prepeare/translate data from app format to network format (encryption/decryption)

Question 8

Applications

Answer 8

offers services directly to apps (SSH, FTP)

Question 9

DNS, DHCP, SSH, HTTP, HTTPS, SNMP, SMTP all examples of what?

Answer 9

Application Layer

Question 10

Encryption, Encoding, SSL, JPEG, MPEG, MIDI all examples of what?

Answer 10

Presentation

Question 11

NFS, RPC, SQL all examples of what?

Answer 11

Session

Question 12

TCP, UDP, RTP all examples of what?

Answer 12

Transport

Question 13

IPv4, IPv6, ICMPv4, ICMPv6, IPX all examples of what?

Answer 13

Network

Question 14

Ethernet, PPP, FDDI, ATM, IEEE 802.5/802.2, HDLC all examples of what?

Answer 14

Data Link

Question 15

Ethernet (IEEE802.3), Wi-fi (IEEE 802.11), FDDI, V.35, V.24 all examples of what?

Answer 15

Physical

Question 16

Data encapsulation

Answer 16

Process of adding headers and trailers using OSI model, starts with application layer

Question 17

Data Decapsulation

Answer 17

extracting info from a reverse OSI model process, starts with Physical Layer

Question 18

Stateful Firewall

Answer 18

More security features, more resource heavy, complex, keeps connection to analyze network traffic

Question 19

Stateless Firewall

Answer 19

Examines individual packets without maintaining a connection

Question 20

TCP vs. UDP

Answer 20

TCP ideal for apps where data integrity is crucial. UDP low-latency comms, suitable for real-time apps

Question 21

ARP

Answer 21

Address Resolution Protocol - operates in Layers 2 + 3 (Every Layer 3 device uses ARP)

Question 22

3-way handshake

Answer 22

responsible for comms between devices that use TCP

“SYN”, “SYN-ACK”, “ACK”

Question 23

TCP/IP Model

Answer 23

Network Access, Internet, Transport, Application

Question 24

In which layer of OSI and TCP/IP models are source and destination logical
addresses added to the packet?

Answer 24

OSI - Network Layer (3), TCP/IP - Internet Layer (3)

Question 25

In which layer of OSI and TCP/IP are source and destination physical addresses added to the frame?

Answer 25

OSI - Data Link Layer (2), TCP/IP - Network Access (1)

Question 26

What does UDP do with corrupted or out-of-order packets?

Answer 26

Nothing, the destination discards corrupted packets