Network+ -- 1.0 Concepts - 1.1 Osi Model Layers Vs Tcp/ip Model Layers

Front 1

What are the 7 layers of the OSI Model?

Back 1

Application
Presentation
Session
Transport
Network
Data-Link
Physical

Front 2

What is layer #1 of the OSI model?

Back 2

Physical

Front 3

STACK

Back 3

Protocols running simultaneously in a network implementation

Front 4

What does the top of the OSI model interact with?

Back 4

The applications running on the computer

Front 5

What does the bottom of the OSI model interact with?

Back 5

The Network Medium that the system transmits its Signals over.

Front 6

What OSI layer converts the data to signals?

Back 6

Physical

Front 7

After the OSI's Physical layer converts data to signals, what part of the actual computer transmits those signals over the network medium?

Back 7

The computer's NIC.
(Network Interface Card)

Front 8

ENCAPSULATION
(in the OSI model)

Back 8

The addition of small, relevant pieces of info at each layer.

Front 9

Protocols provide services for the layer
(above/below) ?

Back 9

Above

Front 10

Protocols request services from the layer
(above\below) ?

Back 10

Below

Front 11

T/F: Protocols can communicate with other protocols on different computers operating in any layer.

Back 11

FALSE. Protocols can only communicate with protocols that operate on the same layer that it does.

Front 12

If a protocol in a layer encrypts data, what would its equivalent protocol on the destination system be responsible for doing?

Back 12

Decrypting the data.

Front 13

What is the item passed up/down stack layers as part of encapsulation?

Back 13

PDU - Protocol Data Unit

Front 14

PDU (Protocol Data Unit)

Back 14

A block of data passed up/down the OSI stack layers that contains control information.

Front 15

Which OSI layers add headers to the PDU?

Back 15

Transport
Network
Data-Link

Front 16

Which layer adds a Footer to the PDU?

Back 16

Data-Link

Front 17

Which OSI layers are not concerned with networking or network addresses?

Back 17

The Top 3:
Application
Presentation
Session

Front 18

T/F: The Application Layer is the application itself.

Back 18

FALSE.

Front 19

Explain how applications interact with the Application Layer.

Back 19

Application processes are initiated within a user application. The data this process creates is handed down to the networking software's Application layer.

ex: A file transfer is initiated within a file transfer program.

Front 20

What are 3 common signal types that computers on a network exchange in order to communicate with each other?

Back 20

Electrical
Light
Radio

Front 21

Electrical signals are used in networks that use ___ cables as a medium.

Back 21

Copper-based

Front 22

Light signals are used in networks that use ___ cables as a medium.

Back 22

Fiber-optic,
and some wireless

Front 23

Radio signals are used in most ___ networks.

Back 23

Wireless

Front 24

To communicate, electrical signals are used to form code in the form of ______.

Back 24

Positive/Negative Voltage

Front 25

To communicate, electrical signals are used to form code in the form of ______.

Back 25

Present/Absent

Front 26

To communicate, electrical signals are used to form code in the form of ______.

Back 26

Frequency Variations

Front 27

Which layer translates data?

Back 27

Presentation

Front 28

The ____ layer puts data into a common format.

Back 28

Presentation

Front 29

The ___ layer converts data from one protocol to another so it can be exchanged between computers on different operating systems.

Back 29

Presentation

Front 30

The ___ layer is responsible for encryption/decryption.

Back 30

Presentation

Front 31

The ___ layer translates EBCDIC -> ASCII.

Back 31

Presentation

Front 32

This is the last "Upper Layer".

Back 32

Session

Front 33

The ___ layer maintains a dialog between computers.

Back 33

Session

Front 34

This layer offers 3 modes for certain things: simplex, and half/full duplex.

Back 34

Session

Front 35

T/F: The Session layer uses acknowledgment (ACK) messages to help coordinate data transfer.

Back 35

True

Front 36

T/F: The Transport layer uses acknowledgment (ACK) messages to help coordinate data transfer.

Back 36

False. Session layer does this

Front 37

HALF DUPLEX

Back 37

Communication goes in both directions, but only one direction at a time.

Front 38

FULL DUPLEX

Back 38

Communication goes in both directions at the same time.

Front 39

The Transport layer connects 2 ____.

Back 39

Machines

Front 40

The Session layer connects 2 ____.

Back 40

Processes

Front 41

SIMPLEX

Back 41

Communication that goes in one direction, like radio.

Front 42

Protocols in this layer are either connectionless or connection-oriented.

Back 42

Transport

Front 43

What layers are linked to the TCP/IP suite?

Back 43

Transport and Network.
TCP (a Transport Protocol)
+
IP (a Network layer protocol)

Front 44

Name a Connection-Oriented protocol.

Back 44

TCP

Front 45

Name a Connectionless protocol.

Back 45

UDP

Front 46

Connection-oriented vs Connectionless. Which protocol type has a bigger header, and why?

Back 46

Connection-oriented.
Delivery is guaranteed, so it uses things like ACK messages and a 3-way handshake. It provides a lot of services to apps in upper layers.

Front 47

Connection-oriented vs Connectionless. Which protocol type has a higher transmission overhead, and why?

Back 47

Connection-oriented.
Delivery is guaranteed, so it uses things like ACK messages and a 3-way handshake. It provides a lot of services to apps in upper layers.

Front 48

In general, what kind of apps use the TCP protocol?

Back 48

Ones that require bit-perfect transmission.
Ex: If even 1 bit of a transferred program file is wrong, it won't run properly.

Front 49

In general, what kind of apps use the UDP protocol?

Back 49

Ones that don't need bit-perfect transmission.
Ex: Streaming video. Delivery isn't guaranteed, and that's OK; quality just suffers a bit.

Front 50

What are the sizes of TCP and UDP headers?

Back 50

TCP -- 20 bytes
UDP -- 8 bytes