Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Phase I Exam Technical Q&A's > Week 7: STP > Flashcards

Week 7: STP Flashcards

1
Q

How is a bridging loop best described?

A

A loop between switches where frames circulate endlessly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the main parameter used in electing the root bridge?

A

Bridge-ID

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What two components make up the Bridge ID?

A

a. The Bridge Priority

b. The MAC Address

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If all switches within the network are left to their default STP values how will the root bridge be elected and why might this be a bad thing?

A

a. The root bridge will be the switch with the lowest MAC Address
b. This is bad because typically the oldest switch within the topology has the lowest MAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Configuration BPDUs are sent by what switch within a network?

A

Only the root bridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the single most important design decision to be made when running STP?

A

The placement of the root bridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the four Spanning Tree port states?

A

a. Blocking
b. Listening
c. Learning
d. Forwarding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens if a port is neither the root port nor a designated port?

A

It is put into the blocking state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the maximum number of root ports that a catalyst switch can have?

A

one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the default “Hello” time for IEEE 802.1D?

A

2 seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which type of Spanning Tree is defined in the IEEE 802.1D Standard

A

Common Spanning Tree (CST)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where should the root bridge be placed within an ideal network?

A

Closest to the center of the network.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What parameter could you change to influence the root bridge selection process?

A

Bridge Priority

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the default 802.1D STP Bridge priority on a catalyst switch

A

32,768

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the default path cost of a Gigabit Ethernet switch port?

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the command syntax to change the path cost of interface Gigabit Ethernet 3/1 to 8

A

“spanning-tree gig3/1 cost 8”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens if the root bridge and another switch are configured with different STP Hello timer values?

A

A loop could form because the two switches are not in sync.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What network diameter value is the basis for the default STP timer calculations?,

A

7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where should PortFast be used?

A

An access-layer switch port connected to a PC or other end user device

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define Transparent Bridge

A

is a common type of bridge that observes incoming network traffic to identify media access control (MAC) addresses.

21
Q

If used, the STP Backbone Fast feature needs to be enabled on which switches in the topology?

A

All

22
Q

Define Bridging loop

A

the process of forwarding a single frame around and around between two switches

23
Q

Define Spanning Tree Protocol

A

Prevents bridging loops by blocking redundant links

24
Q

Define BPDU - Bridge Protocol Data Unit

A

Used to identify loops an elect the root bridge.

25
Q

Define Root bridge

A
  • Elected by having the lowest bridge ID
  • ALWAYS forwards traffic towards the root bridge.
  • Only one per switch
  • On non-root bridges only
  • Can populate the MAC table
26
Q

Define Designated port

A
  • forwarding port, one per link. • On root and non-root bridges
  • All ports on root bridge are designated ports
  • Receives and forward frames towards the root bridge as needed
  • Can populate the MAC table
27
Q

Define Hello Time

A

is the time interval between each Bridge Protocol Data Unit (BPDU) that is sent on a port.
• sends “hello” messages (BPDUs) from the root bridge to the other switches in the network every two seconds.

28
Q

Define Forward Delay

A

the time interval that a switch port spends in both the Listening and Learning states. **The default value is 15 seconds.

29
Q

Define Max Age Time

A

time interval that a switch stores a BPDU before discarding it.
**The default Max Age value is 20 seconds.

30
Q

Define TCN (Topology Change Notification)

A

is generated by a switch when it discovers a topology change (TCN BPCU).

31
Q

Define Common Spanning Tree (CST)

A

IEEE 802.1D, One instance of spanning tree runs for the entire switched network resulting in low CPU requirements, but suboptimal traffic paths when multiple VLANs are used. It is also slow to converge.

32
Q

Define PVST

A

Cisco proprietary version of STP that offer more flexibility than STP. Operates a separate instance of STP for each individual VLAN.

33
Q

Define PVST+

A

Cisco proprietary version of STP that allows devices to interoperate with both PVST and CST.

34
Q

Define Port Fast

A

causes a port to enter the forwarding state almost immediately by decreasing the time of the listening and learning states.

35
Q

Define Uplink Fast

A

Enables fast up-link failover on an access layer switch when dual up-links are connected into the distribution layer. When the primary root port uplink fails, another blocked uplink immediately can be brought up for use.

  • **Is Cisco proprietary
  • **works by finding alternate ports for directly connected links
36
Q

Define Backbone Fast

A

works on finding an alternate path when an indirect link to the root port goes down.
***Is Cisco proprietary

37
Q

Why is it important to know classful networking?

A

To properly segment networks with appropriate subnet masks and users per subnet. Allows for proper addressing of network segments. Also there may be border router issues with auto summarization.

38
Q

What was significant about RFC 1918 address allocation for private internets?

A

a. Private address space is not routable on the internet

b. Allows for the reuse of private address space internally since we are out of IPv4 addresses.

39
Q

Explain what a subnet mask is

A

A 32bit value that allows the device that’s receiving IP packets to distinguish the network ID portion of the IP address from the host portion.

40
Q

Convert 192.168.14.64 255.255.255.192 to binary

A

???

41
Q

Convert 11100011 00010011 11111110 00010001 to decimal

A

???

42
Q

Provide the decimal values for the subnet mask 12.5.129.15 / 14

A

???

43
Q

Host Computer A 192.168.25.3 255.255.255.192 sends a packet to host 192.168.25.68 255.255.255.192. Are these two hosts on the same subnet?

A

???

44
Q

How many total hosts are in the range 172.16.0.0 / 16 thru 172.31.0.0 /16

A

???

45
Q

Host 192.168.100.0 /24. How many useable IP addresses are on this subnet?

A

254

46
Q

Define a Class A network

A

a. in a Class A network address must always be off or 0
b. The IP range for a Class A network is 1-126
c. This provides 8 bits of network addressing and 24 bits of host addressing by default

47
Q

Define a Class B network

A

a. In a Class B the first byte must always be turned on but the second bit must always be turned off
b. IP range for a Class B network is 128-191
c. This provides 16 bits of networking addressing and 16 bits of host addressing by default

48
Q

Define a Class C network

A

a. In a Class C the first 2 bits of the first octet as always turned on but the third bit can never be on.
b. IP range for a Class C network is 192-223
c. This provides 24 bits of networking addressing and 8 bits of host addressing by default

49
Q

Name the reserved private IP address ranges.

A

Class A 10.0.0.0 through 10.255.255.255
Class B 172.16.0.0 through 172.31.255.255
Class C 192.168.0.0 through 192.168.255.255

Phase I Exam Technical Q&A's (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions