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CCENT

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. CABLES: What is the T568B Pinout Standard?
1:O/W - 2:Orange - 3:G/W - 4:Blue - 5:B/W - 6:Green - 7:Brown/W - 8:Brown
255.255.255.252
255.255.255.128
R3(config)#router rip - R3(config-router)#network 192.168.1.2

2. Rip: What causes a triggered update?
Every 32 ip's
(7)Application -(6)Presentation -(5)Session -(4)Transport - (3)Network - (2)Data Link - (1)Physical
Interface changes state (up/down) - A route has entered or exited the unreachable state - a route was installed in the routing table.
Includes sub-net mask in updates making it classless - has authentication - supports variable length subnet mask - uses multicast instead of broadcast - supports manual summarization

3. How many Collision domains are there on a with 1 switch 2 computers?

4. What is Layer 4 in the OSI Model?
Transport
IEEE 802.3ab
Router(config)#ip route {network address} {subnet-mask}
Layer 2

5. RIP: What Algorithm is used in RIP>
Bellman-Ford
Interface changes state (up/down) - A route has entered or exited the unreachable state - a route was installed in the routing table.
Presentation
100

6. What is the Transport PDU called?
180
Segments
IEEE 802.3u
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240

7. RIP Timers: What is an Holddown Timer?
This timer stabilizes routing information and helps prevent routing loops during periods when the topology is converging on new information. Once a route is marked as unreachable - it must stay in holddown long enough for all routers in the topology
R1(config)#router eigrp 7 - R1(config-router)#network 192.168.1.0 0.0.0.3
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds
Switch forwards the frame as soon as it can

8. Rip: how do hold down timers work?
1. Router receives update from neighbor indicating a route down - Router makes route as down and starts holddown timer - If router gets an update indicating route is back holddown is removed - If an update is received indicating route is down again i
By default - the flush timer is set for 240 seconds - which is 60 seconds longer than the invalid timer. When the flush timer expires - the route is removed from the routing table.
IEEE 802.3ab
255.255.192.0

9. RIP Timers: What is an invalid Timer?
Hop Count
180 seconds
F an update has not been received to refresh an existing route after 180 seconds (the default) - the route is marked as invalid by setting the metric to 16. The route is retained in the routing table until the flush timer expires.
Includes sub-net mask in updates making it classless - has authentication - supports variable length subnet mask - uses multicast instead of broadcast - supports manual summarization

10. Subnetting: How many hosts per network if the subnet mask is 255.255.255.240
14 per network
Data-Link
DUAL: Difusing Update Algorithm
Frames

11. Subnetting: where do the networks break with a /25

12. What Layer does CDP operate at?
Segments
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)
Show ip eigrp topology
Layer 2

13. What is Layer 3 in the OSI Model?
255.255.255.128
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
Network
Packets

14. Subnetting: What is a 255.255.252.0 in prefix notation
IEEE 802.3
Query and other router responds with a REPLY packet.
120
/22

15. Subnetting: where do the networks break with a /27

16. Subnetting: where do the networks break with a /30

17. What is the layer 2 PDU called?
It adds the cost of each jump - R1 to R2 over a t1 is a cost of 64 - R2 to computer is a cost of 1. Total cost of route is 65
Frames
Packets
Shortest path first - (SPF)

18. Rip: What does v2 have that v1 does not?
255.255.192.0
Every 8 ip's
Includes sub-net mask in updates making it classless - has authentication - supports variable length subnet mask - uses multicast instead of broadcast - supports manual summarization
Session

19. EIGRP: What is the hello packet used for?
2 - each port is it's own collision domain
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds

20. EIGRP: What is the default administrative distance?
Use command bandwidth {bandwidth in KPS} or the command ip ospf cost {amount} both in the interface you want to change
255.255.0.0
Network
100

21. Subnetting: What is a /27 in Decimal
255.255.255.224
255.255.255.252
R1(config)#router rip - R1(config-router)#version 2
Frames

22. What is Layer 6 in the OSI Model?
Frames
Add the magic number to the network minus 1
Every 16 ip's
Presentation

23. Subnetting: What is a 255.255.255.240 in prefix notation
/28
1 - everything hooked to the hub is in the same collision domain
1:O/W - 2:Orange - 3:G/W - 4:Blue - 5:B/W - 6:Green - 7:Brown/W - 8:Brown
110

24. EIGRP: What is the range of Autonomous System numbers?
1 - everything hooked to the hub is in the same collision domain
Can be multicast or unicast depending on number of routers - Update packets. Responds with an ACK packet
Every 8 ip's
1-65535

25. IEEE Standards: Fast Ethernet
This timer stabilizes routing information and helps prevent routing loops during periods when the topology is converging on new information. Once a route is marked as unreachable - it must stay in holddown long enough for all routers in the topology
IEEE 802.3u
Network
Data-Link

26. Subnetting: How many hosts per network if the subnet mask is 255.255.255.252
255.255.255.252
/24
2 hosts
/22

27. Rip Timers: How long is the default for Flush timer.
R
R1(config)#router rip - R1(config-router)#version 2
126 per network
60

28. EIGRP: What is the name of the algorithm used for EIGRP?
DUAL: Difusing Update Algorithm
Data-Link
/24
Frames

29. OSPF: how do you change the cost of an interface for OSPF?
Use command bandwidth {bandwidth in KPS} or the command ip ospf cost {amount} both in the interface you want to change
F an update has not been received to refresh an existing route after 180 seconds (the default) - the route is marked as invalid by setting the metric to 16. The route is retained in the routing table until the flush timer expires.
Frames
Switch forwards the frame as soon as it can

30. Name the TCP/IP Layers
1 - everything hooked to the hub is in the same collision domain
Switch forwards the frame as soon as it can
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical
255.255.255.252

31. What gets the clock rate - DCE or DTE?
Packets
255.255.255.128
DCE
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical

32. How many Collision domains are there on a with 1 hub and 2 computers?
1 - everything hooked to the hub is in the same collision domain
Every 8 ip's
Router(config)#ip route {network address} {subnet-mask}
/22

33. Rip: What is the command to enable Ripv2?
Router(config)#ip route {exit-interface}
R1(config)#router rip - R1(config-router)#version 2
The metric is called cost - and refers to the speed of the port - IE 56kps = 1785 where Fast Ethernet = 1
Shortest path first - (SPF)

34. Command for a static route with 'Next Hop' Address
Router(config)#ip route {network address} {subnet-mask}
Bandwidth - Delay - reliability and Load
60
1. Router receives update from neighbor indicating a route down - Router makes route as down and starts holddown timer - If router gets an update indicating route is back holddown is removed - If an update is received indicating route is down again i

35. What is the layer 4 PDU called?
Every 16 ip's
126 per network
Transport
Segments

36. Subnetting: where do the networks break with a /28

37. Subnetting: What is a 255.128.0.0 in prefix notation
Every 64 ip's
Physical
/9
DUAL: Difusing Update Algorithm

38. Rip Timers: How long is the default for Holddown timer.
180
255.255.0.0
R1(config)# router OSPF 1 - R1(config-router)#network 10.1.1.0 0.0.0.15 area 0
30 per network

39. EIGRP: What is the commands to enable EIGRP for autonomous area 7 and to route network 192.168.1.0 /30
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
Switch forwards the frame as soon as it can
DUAL: Difusing Update Algorithm
R1(config)#router eigrp 7 - R1(config-router)#network 192.168.1.0 0.0.0.3

40. Subnetting: What is a /25 in Decimal
Frames
255.255.255.128
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical
Show ip eigrp topology

41. Rip Timers: How long is the default for Invalid timer.
It adds the cost of each jump - R1 to R2 over a t1 is a cost of 64 - R2 to computer is a cost of 1. Total cost of route is 65
180 seconds
Data-Link
DCE

42. What is the Data-Link PDU called?
Packets
Frames
Data-Link
DCE

43. Subnetting: What is a /30 in Decimal
Every 32 ip's
255.255.192.0
255.255.255.252
Every 64 ip's

44. How do you find the magic number for subnetting?
R1(config)#int s0/0 - R1(config-inf)clock rate 64000 <-- on the DCE
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
R
180

45. RIP Timers: What is an Flush Timer?
Data-Link
Every 16 ip's
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
By default - the flush timer is set for 240 seconds - which is 60 seconds longer than the invalid timer. When the flush timer expires - the route is removed from the routing table.

46. Subnetting: where do the networks break with a /29

47. Switching Methods: What is Fragment-free?
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
Every 32 ip's
Bandwidth - Delay - reliability and Load
1 - everything hooked to the hub is in the same collision domain

48. Subnetting: where do the networks break with a /26

49. Subnetting: How many hosts per network if the subnet mask is 255.255.255.224
62 per network
30 per network
1 - everything hooked to the hub is in the same collision domain
Every 16 ip's

50. Switching Methods: What is Cut-through?
Every 64 ip's
Router(config)#ip route {network address} {subnet-mask}
Every 16 ip's
Switch forwards the frame as soon as it can