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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. Subnetting: What is a /30 in Decimal
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds
255.255.255.252
Network
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

2. IEEE Standards: Ethernet
IEEE 802.3
Packets
62 per network
Application

3. How many Collision domains are there on a with 1 hub and 1 bridge 2 computers?
2 - the bridge separates the collision domain
Add the magic number to the network minus 1
180
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database

4. EIGRP: What is the commands to enable EIGRP for autonomous area 7 and to route network 192.168.1.0 /30
Packets
Switch forwards the frame as soon as it can
R1(config)#router eigrp 7 - R1(config-router)#network 192.168.1.0 0.0.0.3
D

5. RIP: Commands to enable ripv1 on a router and add a route to 192.168.1.2
30 per network
Interface changes state (up/down) - A route has entered or exited the unreachable state - a route was installed in the routing table.
R3(config)#router rip - R3(config-router)#network 192.168.1.2
Bellman-Ford

6. What is the Data-Link PDU called?
Bandwidth - Delay - reliability and Load
1-65535
Frames
D

7. What is the layer 3 PDU called?
Packets
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
62 per network
/24

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

9. How many Collision domains are there on a with 1 hub and 2 computers?
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
1 - everything hooked to the hub is in the same collision domain
DUAL: Difusing Update Algorithm
Presentation

10. What is the Transport PDU called?
Switch forwards the frame as soon as it can
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
Segments
R1(config)# router OSPF 1 - R1(config-router)#network 10.1.1.0 0.0.0.15 area 0

11. Name the TCP/IP Layers
Use command bandwidth {bandwidth in KPS} or the command ip ospf cost {amount} both in the interface you want to change
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical
Packets
Packets

12. What is the Network PDU called?
Packets
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
1-65535
Switch forwards the frame as soon as it can

13. EIGRP: How do you view if there are any successor routes?
Presentation
Show ip eigrp topology
IEEE 802.3z
Router(config)#ip route {network address} {subnet-mask}

14. OSPF: What Algorithm is used?
Shortest path first - (SPF)
Bandwidth - Delay - reliability and Load
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
180 seconds

15. What is the metric for EIGRP
Bandwidth - Delay - reliability and Load
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
Session
110

16. Subnetting: What is a 255.128.0.0 in prefix notation
Physical
Layer 2
Every 128 ip's
/9

17. What is Layer 5 in the OSI Model?
Session
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
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds
The metric is called cost - and refers to the speed of the port - IE 56kps = 1785 where Fast Ethernet = 1

18. What is the layer 4 PDU called?
Packets
Segments
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
Use command bandwidth {bandwidth in KPS} or the command ip ospf cost {amount} both in the interface you want to change

19. What Layer does CDP operate at?
Query and other router responds with a REPLY packet.
Switch forwards the frame as soon as it can
Layer 2
/28

20. What is Layer 6 in the OSI Model?
180
Presentation
14 per network
Segments

21. Switching Methods: What is Fragment-free?
/22
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
Frames
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

22. IEEE Standards: Gibabit Ethernet (Copper)
255.255.255.224
Includes sub-net mask in updates making it classless - has authentication - supports variable length subnet mask - uses multicast instead of broadcast - supports manual summarization
IEEE 802.3ab
Frames

23. RIP: What Algorithm is used in RIP>
D
100
Bellman-Ford
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

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

25. EIGRP: What packet is used to search for networks?
255.255.255.252
Query and other router responds with a REPLY packet.
Periodic Updates of their routing table
Router(config)#hostname R1 - R1(config)#line VTY 0 4 - R1(config-line)#login local - R1(config-line)#transport input telnet ssh - R1(config-line)#exit - R1(config)#username {user} password {pass} - R1(config)#ip domain-name {domainname} - R1(config)#

26. Subnetting: How many hosts per network if the subnet mask is 255.255.255.192
62 per network
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
Bandwidth - Delay - reliability and Load
Packets

27. What is Layer 2 in the OSI Model?
The metric is called cost - and refers to the speed of the port - IE 56kps = 1785 where Fast Ethernet = 1
Data-Link
Bandwidth - Delay - reliability and Load
62 per network

28. Rip: Command to prevent rip updates on an interface
Physical
Network
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
Router(config)# router rip - Router(config-router)# passive-interface fa0/0

29. Command for a static route with 'Next Hop' Address
Add the magic number to the network minus 1
120
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
Router(config)#ip route {network address} {subnet-mask}

30. OSPF: How does OSPF calulate the cost of each route - to figure out which way to go?
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
255.255.0.0
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
110

31. What gets the clock rate - DCE or DTE?
255.255.255.224
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
Router(config)#ip route {network address} {subnet-mask}
DCE

32. Subnetting: What is a /16 in Decimal
255.255.0.0
60
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.
/9

33. Rip: What is the command to enable Ripv2?
Bellman-Ford
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
2 - each port is it's own collision domain
R1(config)#router rip - R1(config-router)#version 2

34. CABLES: What is the T568A Pinout Standard?
R3(config)#router rip - R3(config-router)#network 192.168.1.2
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
Packets
1:O/W - 2:Orange - 3:G/W - 4:Blue - 5:B/W - 6:Green - 7:Brown/W - 8:Brown

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

36. IEEE Standards: Fast Ethernet
1:O/W - 2:Orange - 3:G/W - 4:Blue - 5:B/W - 6:Green - 7:Brown/W - 8:Brown
R1(config)#int s0/0 - R1(config-inf)clock rate 64000 <-- on the DCE
IEEE 802.3u
Bandwidth - Delay - reliability and Load

37. Subnetting: How many hosts per network if the subnet mask is 255.255.255.224
180
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds
14 per network
30 per network

38. OSPF: Commands to enable OSPF area 0 and advertise network 10.1.1.1 /28
Every 32 ip's
R1(config)# router OSPF 1 - R1(config-router)#network 10.1.1.0 0.0.0.15 area 0
Use command bandwidth {bandwidth in KPS} or the command ip ospf cost {amount} both in the interface you want to change
Router(config)#ip route {network address} {subnet-mask}

39. Rip Timers: How long is the default for Invalid timer.
Session
Can be multicast or unicast depending on number of routers - Update packets. Responds with an ACK packet
Every 4 ip's
180 seconds

40. OSPF: What is the process used by OSPF to build a routing table (step by step)
Layer 2
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
Frames
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)

41. Subnetting: How many hosts per network if the subnet mask is 255.255.255.240
R
Segments
DUAL: Difusing Update Algorithm
14 per network

42. Subnetting: What is a /18 in Decimal
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds
255.255.192.0
255.255.0.0
2 hosts

43. Rip and EIGRP use what to keep other routers aware of their status?
DCE
Periodic Updates of their routing table
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
IEEE 802.3ab

44. Using the magic number how to you figure the broadcast?
255.255.255.224
Add the magic number to the network minus 1
180
120

45. EIGRP: What is the default administrative distance?
Every 8 ip's
Packets
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.
100

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

47. Rip: how do hold down timers work?
DCE
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
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.
R1(config)# router OSPF 1 - R1(config-router)#network 10.1.1.0 0.0.0.15 area 0

48. Symbol for EIGRP on a Show ip route
1:O/W - 2:Orange - 3:G/W - 4:Blue - 5:B/W - 6:Green - 7:Brown/W - 8:Brown
255.255.255.224
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
D

49. Subnetting: What is a 255.255.255.240 in prefix notation
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
14 per network
Pins 1+2 swap places with pins 3+6
/28

50. Subnetting: What is a 255.255.255.0 in prefix notation
/24
(7)Application -(6)Presentation -(5)Session -(4)Transport - (3)Network - (2)Data Link - (1)Physical
Router(config)#ip route {exit-interface}
Data-Link