Block 7

Question 0

Data link layer addresses are also referred to as (4 others)

Answer 0

Physical, hardware machine or MAC address

Question 1

What defines how devices are addressed at the data link layer

Answer 1

Physical addressing

Question 2

What consists of the data link layer specifications that often define how devices are to be physically and logically connected?

Answer 2

Network topology

Question 3

Error detection uses CRC or FCS to detect errors in transmission. What layers are responsible for the actual error correction or request or request for transmission of a frame?

Answer 3

Higher layers

Question 4

What reorders frames that are received out of sequence?

Answer 4

Sequencing of data frames

Question 5

What moderates the transmission of data so that the receiving device is not overwhelmed with more than it can handle at one tim?

Answer 5

Flow control

Question 6

Switches primary method of flow control is?

Answer 6

Buffering

Question 7

What connects multiple network segments at the data link layer of the OSI model?

Answer 7

Bridge

Question 8

Layer 2 switching is very efficient because

Answer 8

No modification to packet
Only to frame encapsulation
And only when the data packet is passing through dissimilar media

Question 9

Bridges are ___________ based and switches are __________ based

Answer 9

Software

Hardware

Question 10

Bridges have a ________ spanning tree control and switches have a _________ spanning tree control

Answer 10

Limited

Advanced

Question 11

How many ports do switches have?

Answer 11

Hundreds

Question 12

How many ports do bridges have?

Answer 12

16

Question 13

A physical or logical network segment in which data packets can collide with each other

Answer 13

Collision domain

Question 14

__________ reduces the chances of this happening by preventing more than one device from accessing the Collision domain at the same time, but collisions can still occur.

Answer 14

Ethernet 802.3 CSMA/CD

Question 15

All network segments connected by layer 1 devices exist on a ___________ collision domain.

Answer 15

Single

Question 16

How many collision domains are on layer 2 devices ?

Answer 16

Each interface is a separate collision domain

Question 17

A logical network segment defined by its router port

Answer 17

Broadcast domain

Question 18

Devices physically connected to same media or layer 2 device will be on

Answer 18

Same broadcast domain

Question 19

What do switches use to build and maintain MAC address tables ?

Answer 19

Application-specific integrated circuits (ASICs)

Question 20

What do switches use to filter traffic?

Answer 20

MAC address from the host NIC

Question 21

Layer 2 switches provide ?

Answer 21

Hardware-based bridging
Wire speed
Low latency
Low cost

Question 22

Most common type of switches

Answer 22

Ethernet switches

Question 23

3 major functions of layer 2 switches

Answer 23

Address learning
Forward/filter decision
Loop advance

Question 24

3 methods of frame switching methods

Answer 24

``` Store and forward Cut through(real time) Fragment free(modified cut-through) ```

Question 25

Where are the MAC address tables stored in the switches?

Answer 25

RAM

Question 26

Most switches hold up to how many MAC address in their table?

Answer 26

8000

Question 27

If a workstation does not talk for a period of time on the network chances are?

Answer 27

The MAC address has aged out (removed) from the table

Question 28

What helps I preserve bandwidth I other network segments?

Answer 28

Frame filtering

Question 29

In this Frame switching method the switch copies the entire frame into its buffers and computes the CRC. *Best for error free but greatest amount of processing time?

Answer 29

Store-and-forward

Question 30

Also called real time, in this frame switching method the LAN switch only copies the destination address onto it's on board buffers. *reduces latency because no error checks but fastest method

Answer 30

Cut-through

Question 31

Also called modified cut-through, this frame switching method waits 64 bytes(collision window) to pass before forwarding. *better error checking than cut-through mode with no increase in latency

Answer 31

Fragment free

Question 32

If a packet has an error it almost always occurs within the first __________.

Answer 32

64 bytes

Question 33

Why is it a good idea to use multiple (redundant) links between switches and multiple switches?

Answer 33

To avoid a single point of failure

Question 34

If loop avoidance schemes are not put in place, the switches will flood broadcasts endlessly throughout and internetwork.

Answer 34

Broadcast storms

Question 35

If a device receives multiple copies of the same frame because the frame can arrive from different segments at the same time what problem is occurring?

Answer 35

Multiple frame copies

Question 36

One of biggest problems generating through an internetwork where loops occur within loops

Answer 36

Multiple loops

Question 37

Use by layer 2 devices to stop network loops in networks that have more than one physical link to the same network

Answer 37

STP spanning tree protocol

Question 38

An external component that allows you local direct access to the switch during configuration

Answer 38

Console port

Question 39

And external component where you will connect your end devices such as your computers or printers.

Answer 39

Network interfaces

Question 40

And internal component where the diagnostics and boot up routines are stored. the contents of this type of memory cannot be changed since they are burned in the chip.

Answer 40

Rom

Question 41

Internal component that holds the Internet work operating system. this type of memory is similar to EEPROM.

Answer 41

Flash memory

Question 42

I'm going to start up operation the iOS is copied from the ______memory into ram for execution.

Answer 42

Flash

Question 43

This internal components type of memory is call nonvolatile memory. When Powers is removed from the switch the content of this memory will remain unchanged. Used to store start -up config file

Answer 43

NVRAM

Question 44

This type of memory is called volatile memory. when power is removed from the switch the content of this memory will be lost.

Answer 44

Ram

Question 45

A logical grouping of network computers and resources connected to administratively defined ports on a layer 2 switch.

Answer 45

VLAN

Question 46

This is also called a broadcast domain and all connected devices see all broadcast packets that are transmitted.

Answer 46

Flat network

Question 47

What are VLAM benefits

Answer 47

(I)ncreased security (N)o geographical barrier (f)lexibility and scalability (b)roadcast control

Question 48

What are the two types of the VLAN port membership assignments

Answer 48

Dynamic and static

Question 49

Which VLAN membership takes more work upfront but is easier to maintain

Answer 49

Dynamic VL AN

Question 50

Which VLAN membership requires less work initially but is more time-consuming for an admin to maintain

Answer 50

Static VLAN

Question 51

What are the two different link modes

Answer 51

Access link or trunk link

Question 52

What allows Cisco switches to automatically negotiate with other Cisco devices when they connect

Answer 52

Dynamic trunking protocol

Question 53

Switches without dynamic trunking protocol cannot negotiate and must be manually configured as

Answer 53

Access or truck link through static assignments

Question 54

A link that is assigned to one VLAN

Answer 54

Access link

Question 55

This link will carry traffic for all VLANs unless you specify otherwise

Answer 55

Trunk link

Question 56

What is the minimum speed for Trunk link

Answer 56

100 Mbps

Question 57

What are the two frame identification methods that Cisco supports

Answer 57

Inter-switch link (ISL) | IEEE 802.1q

Question 58

What uniquely assigns a user defined ID to each frame also call frame tagging

Answer 58

Frame identification

Question 59

VLAN frame identification places a ____________ in the header of each frame as it is forwarded through the switch fabric on Trunk links

Answer 59

Unique identifier

Question 60

Cisco proprietary protocol that is a way of encapsulating a VLAN frame with an added headed and trailer.

Answer 60

ISL inter-switch link protocol

Question 61

This process enables VLANs to be multiplexed over a trunk link through an external encapsulation method. *external encapsulation method

Answer 61

ISL

Question 62

An open source standard method of frame tagging . *internal tagging method

Answer 62

IEEE 802.1q

Question 63

A Cisco proprietary protocol that eases management of VLANs in an internetwork.

Answer 63

VLAN trunking protocol (VTP)

Question 64

Allows for creation, addition, deletion of control within an administrative domain .

Answer 64

VTP

Question 65

How many VTP domains do a switch belong to?

Answer 65

1

Question 66

A switch shares VLAN information with other switches in

Answer 66

The same domain

Question 67

What are the three modes a switch can operate in?

Answer 67

Server Client Transparent

Question 68

A central point(management) for VLAN creation within a domain

Answer 68

Server

Question 69

What mode receives information from a server and can forward received updates to other switches ?

Answer 69

Client

Question 70

This mode does not partake on VTP domain but can still receive and forward VTP advertisements through trunk links

Answer 70

Transparent

Question 71

What do VTP advertisements include?

Answer 71

Management domain name Configuration revision # VLANs Parameters for each VLAN

Question 72

If a client receives an advertisement that has a higher revision #, what will happen

Answer 72

It will overwrite the database in NVRAM with the database being advertised

Question 73

If a switch was connected to another network it's best to clear everything from its memory and then power-cycle it. Reason?

Answer 73

So a high revision # will not overwrite the system

Question 74

What provides consistent network availability when an outrage occurs for one link?

Answer 74

Spanning-tree protocol (STP)

Question 75

A standardized protocol that provides a stable fault-tolerant loop free environment while selecting the fastest network path when redundant links exist with in a internetwork

Answer 75

STP

Question 76

Which algorithm chooses one path on which to forward frames and places the other redundant links in blocking state to stop any network loops from occuring

Answer 76

Spanning-tree algorithm

Question 77

What device will be the loop bridge?

Answer 77

The device with the lowest bridge ID

Question 78

All ports on the root bridge are called __________ and are set to _________

Answer 78

Designated ports | Forwarding "meaning they will pass data@

Question 79

After the root bridge is selected all other remaining switches become the ____________

Answer 79

Non-root bridge

Question 80

What is the main device that other switches in the network will "key on" to set their ports to forwarding or blocking to establish a path

Answer 80

Root bridge

Question 81

Later 2 devices with STP capability will exchange info using the ______________

Answer 81

Bridge protocol data units (BPDUs)

Question 82

How many bytes is the bridge iD and what does it include

Answer 82

8 bytes and includes the default priority plus the MAC of the device

Question 83

The default priority for all devices running the IEEE version of STP is?

Answer 83

32768

Question 84

Root ports are in _______ mode and provide a constant connection to the root bridge from the non root bridge so advertisements and updates are received.

Answer 84

Forwarding

Question 85

These ports are used to prevent loops. after a switch has determine the best path to the bridge all other ports are placed in the blocking state

Answer 85

Non designated port (blocked)

Question 86

This occurs when bridges and switches have completed the transitions to either the forwarding or blocking state

Answer 86

Convergence

Question 87

How long can convergence take up to

Answer 87

50 secs

Question 88

How much data is forwarded doing convergence

Answer 88

None

Question 89

By default what runs on all switch ports

Answer 89

Spanning tree protocol

Question 90

whenever a New port is enable spanning tree goes through the following port states to get that port to be either forwarding or blocking

Answer 90

Blocking- will not forward frames Listening- listens to make sure no loops before pass in frames Learning -learns Mac addresses and builds tables Forwarding- bridge port able to send and receive data ...a port will never be placed in forward state unless there are no redundant links

Question 91

What is use to speed up convergence on ports that are connected to workstations and servers or other devices that will not cause layer 2 loops

Answer 91

Spanning tree portfast

Question 92

What are the three spanning tree protocol standards

Answer 92

CST common spanning tree PVST Per-VLAN spanning tree PVST + Per VLAN spanning Tree +

Question 93

Also called mono spanning tree because it uses only one spanning tree instance regardless of the size of the later 2 networks or number of VLANs

Answer 93

CST common spamming trees

Question 94

Cisco proprietary, uses ISL and runs a separate instance for each VLAN. Smaller STP implementation and easier convergence

Answer 94

Per-VLAN spanning tree (PVST)