Networking Fundamentals - Ch 2 - Osi Model

Front 1

Number of layers in the OSI model?

Back 1

7

Front 2

How many layers is the communications subnetwork of the OSI model?

Back 2

3 (Pg 33)

Front 3

Which of the following layers deals with the serial transfer of data?
a - physical
b - data link
c- network
d - session

Back 3

a - physical

Front 4

What protocol uses port 3389?

Back 4

RDP - remote desktop protocol

Front 5

What protocol uses port 161?

Back 5

SNMP - simple network management protocol

Front 6

What protocol uses port 80?

Back 6

HTTP - hypertext transfer protocol

Front 7

What protocol uses port 443?

Back 7

HTTPS - hypertext transfer protocol secure

Front 8

What protocol uses port 53?

Back 8

DNS - domain name system

Front 9

What protocol uses port 21?

Back 9

FTP - file transfer protocol

Front 10

What protocol uses port 25?

Back 10

SMTP - simple mail transfer protocol

Front 11

What protocol uses port 110?

Back 11

POP - post office protocol v3

Front 12

What protocol uses port 143?

Back 12

IMAP - internet access message protocol

Front 13

What protocol uses port 23?

Back 13

Telnet, used to remotely connect to and manage computers using a command-line interface.

Front 14

What is a general definition of the OSI model?

Back 14

The Open Systems Interconnection reference model is used to define how data communications occurs on computer networks. It is divided into 7 layers, each of which provide services to adjacent layers and are associated with protocols and devices.
Pg 31

Front 15

Name all OSI layers from 7-1 using the mnemonic "all people seem to need data processing"

Back 15

7. Application
6. Presentation
5. Session
4. Transport
3. Network
2. Data link
1. Physical
Pg 32

Front 16

Which layer of the OSI model deals with cables, jacks, hubs, and MAUs?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 16

1 Physical.
Also, this layer communicates in bits .

Front 17

Which layer of the OSI model deals NICs, WAPs, and bridges?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 17

2 Data Link.
IEEE 802 standards live on this layer as well.
Also, this layer communicates in frames.

Front 18

Which layer of the OSI model deals routers and switches?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 18

3 Network.
Also, this layer communicates in packets.

Front 19

Which layer of the OSI model breaks messages up into segments, sends them through the subnet, and reassembles them on the other side?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 19

4 Transport.
The key word is segments, which is how the transport layer sends data.

Front 20

Which layer of the OSI model controls inbound and outbound ports?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 20

4 Transport.

It also governs the transmission of messages through the OSI communications subnetwork.

Front 21

Which layer of the OSI model monitors your connections (log on/off) to networks?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 21

5 Session.

Front 22

Which layer of the OSI model controls the encryption and compression of data? Hint - HTTPS lives on this layer.
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 22

6 Presentation.

Front 23

Which layer of the OSI model is involved with code conversion, data compression, and file encryption?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 23

6 Presentation.

Front 24

Message creation - and therefore packet creation - begin on this layer. Also present here are end-user protocols such as FTP, SMTP, Telnet, and RAS. Which layer of the OSI model are we talking about?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 24

7 Application.

Front 25

Which layers are considered the communications subnetwork of the OSI model?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 25

1-3

Front 26

What protocol does ping use to send packets to other computers on the network?
a - ICMP
b - ARP

Back 26

ICMP, or internet control message protocol

Front 27

What is the Address Resolution Protocol good for?

Back 27

ARP or Address Resolution Protocol, lives on layer 3 of the OSI model and translates IP addresses to MAC addresses. This allows communication between layers 2 and 3.
Pg 37

Front 28

Name some of the differences between layer 2 and 3 switches

Back 28

Layer 2 Layer 3
MAC addressing IP addressing
forwards frames forwards packets
can't analyze data can analyze data packets
similar to a bridge more like a router

Front 29

Which are considered the "upper layers" of the OSI model?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 29

4-7

Front 30

When you use ping to detect live computers on the network, what protocol is being implemented?

Back 30

ICMP - internet control message protocol

Front 31

Which ports are registered by vendors for their proprietary applications?
a - 0-1023
b - 1024-49,151
c - 49,152 - 65,535

Back 31

b - 1024-49,151
Pg 40

Front 32

If you suspect that your computer's NIC is having trouble sending the correct frames of data along the network, at which layer of the OSI model should you start your investigation?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 32

2 - Data link
Pg 47

Front 33

When you run the netstat -an command, you notice many TCP connections being made. What layer of the OSI model is TCP referring to?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 33

4 - Transport

Front 34

If you need to look at the MAC address of all the computers a user has accessed in the recent past, which command should you use?
a - ping 127.0.0.1
b - netstat -a
c - arp - a
d - arp -s

Back 34

c - arp -a
Pg 36

Front 35

When you connect to a secure website your data sent to it is encrypted in an encoded format. This change to your data takes place on which OSI model layer?
1 - Physical
2 - Data link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application

Back 35

6 Presentation.
Pg 48

Front 36

While analyzing a packet of data using wireshark, you notice that the frame size is bigger than the packet it contains. Why is this so?

Back 36

It is because the packet is encapsulated inside the frame.

Front 37

A coworker's computer seems to be connecting to various internet sites on its own and is getting a lot of random pop ups. What command would you use to analyze which IP addresses and ports the computer is connecting to? What layers of the OSI model do the IP addresses and ports correspond to?

Back 37

netstat -an
4 - Transport layer for dealing with ports
3 - Network layer for dealing with IP addresses