Layers

Question 2

What are the 7 layers of the OSI Model?

Answer 2

L7 ApplicationL6 PresentationL5 SessionL4 TransportL3 NetworkL2 Data LinkL1 Physical

Question 3

Name some protocols and services that run at L7 (Application Layer)?

Answer 3

Email Protocols SMTP and Pop3TelnetHTTPFile Transfer Protocol( FTP)Simple Network Management Protocol (SNMP)

Question 4

Name the four primary tasks that the Presentation Layer is concerned with.

Answer 4

1. Compatibility with the operating system.2. Proper encapsulation of data for network transmission.3. Data formatting (ASCII, Binary)4. Data encryption, compression and translation

Question 5

What is the Application Layer (L7)?

Answer 5

It’s where the end users interact with the network.

Question 6

What is the Presentation Layer (L6)?

Answer 6

How the data is presented.

Question 7

What are some file types in the Presentation Layer?

Answer 7

JPEG, ASCII, GIF, MPEG, MIDI, EBCDIC, and TIFF

Question 8

What is the Session Layer (L5)?

Answer 8

It handles the creation, maintenance and teardown of communications between those two hosts.

Question 9

What is the Transport Layer (L4)?

Answer 9

It establishes a logical end-to-end connection between two systems, segment data received from the upper layers of the OSI model, and to make sure the data gets to the destination in the correct order and free of errors.

Question 10

What are the two methods for transporting data?

Answer 10

Connection-oriented, referring to TCP and connectionless, referring to UDP.

Question 11

Besides TCP and UDP, what is also a Transport Layer?

Answer 11

SPX (Sequenced Packet Exchange) NCP (Novell Netware protocol.

Question 12

The Network Layer (L3) is also called what?

Answer 12

The Routing Layer

Question 13

What layer does IP run at?

Answer 13

The Network Layer

Question 14

What is the two-question process in the Network Layer?

Answer 14

What valid paths exist from the local router to a given destination?What is the best path (optimal path) to take to get there?

Question 15

What layer is the Data Link?

Answer 15

L2

Question 16

What is a WAP?

Answer 16

Wireless Access Points

Question 17

What runs at L2?

Answer 17

Cable Modems and DSL Modems

Question 18

What four major specifications run at L2?

Answer 18

EthernetHigh Data Link Control (HDLC)Point-to-Point Protocol (PPP)Frame Relay

Question 19

What is HDLC?

Answer 19

High Data Link Control

Question 20

What is PPP?

Answer 20

Point-to-Point Protocol

Question 21

Does the Data Link Laer perform error detection?

Answer 21

Yes

Question 22

The Data Link Layer performs error detection through the what?

Answer 22

The Frame Check Sequence

Question 23

MAC addresses are sometimes called what?

Answer 23

hardware addresses and physical addresses

Question 24

What is a burned-in address?

Answer 24

MAC address that is physically burned into the Network Interface Card (NIC)

Question 25

What does NIC stand for?

Answer 25

Network Interface Card

Question 26

What does BIA stand for?

Answer 26

a burned-in address

Question 27

Physical addresses are used in what layer?

Answer 27

Data Link Layer

Question 28

A physical address is used to deliver?

Answer 28

A frame, not a physical layer address

Question 29

Physical cable, pins, Connectors and the electrical current, run at which layer?

Answer 29

Physical Layer

Question 30

Which layers is the data simply called data?

Answer 30

Application, Presentation and Session Layers

Question 31

Which layer is data placed into segments?

Answer 31

Transport Layer

Question 32

What layer is data placed into packets?

Answer 32

Network Layer

Question 33

What layer is data placed into frames?

Answer 33

Data Link Layer

Question 34

What layer takes the form of bits?

Answer 34

Physical Layer

Question 35

Which layer is all ones and zeros?

Answer 35

Physical Layer

Question 36

Which layer adds a header and a trailer?

Answer 36

L2 Data Link Layer

Question 37

What does PDU stand for?

Answer 37

Protocol Data Unit

Question 38

What is a Protocol Data Unit?

Answer 38

A combination of data and layer-specific header.

Question 39

SPX stands for?

Answer 39

Sequenced Packet Exchange

Question 40

SNMP stands for?

Answer 40

Simple Network Management Protocol