Test your basic knowledge |

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. OSPF: What is the default administrative distance?
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
Can be multicast or unicast depending on number of routers - Update packets. Responds with an ACK packet
/28
110

2. EIGRP: What is the range of Autonomous System numbers?
1-65535
180 seconds
Segments
180

3. What are the commands to setup SSH?
Layer 2
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)#
30 per network
Every 64 ip's

4. What Layer does CDP operate at?
Packets
D
Layer 2
DUAL: Difusing Update Algorithm

5. Subnetting: What is a 255.128.0.0 in prefix notation
/9
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)#
60
Every 32 ip's

6. Rip and EIGRP use what to keep other routers aware of their status?
100
180 seconds
DCE
Periodic Updates of their routing table

7. Subnetting: How many hosts per network if the subnet mask is 255.255.255.252
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)
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.
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 hosts

8. What is the layer 3 PDU called?
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical
Every 8 ip's
Packets

9. How many Collision domains are there on a with 1 hub and 1 bridge 2 computers?
2 - the bridge separates the collision domain
60
Presentation
Segments

10. RIP: What Algorithm is used in RIP>
Hop Count
Switch forwards the frame as soon as it can
Every 128 ip's
Bellman-Ford

11. IEEE Standards: Gibabit Ethernet (Fibre)
IEEE 802.3z
60
180
Transport

12. Rip: What is the command to enable Ripv2?
Router(config)#ip route {network address} {subnet-mask}
R3(config)#router rip - R3(config-router)#network 192.168.1.2
Show ip eigrp topology
R1(config)#router rip - R1(config-router)#version 2

13. Name the OSI Layers
120
Every 32 ip's
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
(7)Application -(6)Presentation -(5)Session -(4)Transport - (3)Network - (2)Data Link - (1)Physical

14. Subnetting: What is a 255.255.255.0 in prefix notation
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
/24
R1(config)# router OSPF 1 - R1(config-router)#network 10.1.1.0 0.0.0.15 area 0

15. Rip: What causes a triggered update?
The metric is called cost - and refers to the speed of the port - IE 56kps = 1785 where Fast Ethernet = 1
Every 4 ip's
Interface changes state (up/down) - A route has entered or exited the unreachable state - a route was installed in the routing table.
Transport

16. RIP Timers: What is an Flush Timer?
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.
Every 16 ip's
60
Presentation

17. What is Layer 7 in the OSI Model?
Every 64 ip's
Packets
Application
1-65535

18. What is the Network PDU called?
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)#
Layer 2
180 seconds
Packets

19. Rip: What does v2 have that v1 does not?
120
Switch forwards the frame as soon as it can
Includes sub-net mask in updates making it classless - has authentication - supports variable length subnet mask - uses multicast instead of broadcast - supports manual summarization
/22

20. RIP: What is the default Administrative Distance?
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
62 per network
120
180

21. Symbol for EIGRP on a Show ip route
Application
/9
D
Frames

22. CABLES: What is the T568A Pinout Standard?
Router(config)#ip route {network address} {subnet-mask}
D
100
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown

23. OSPF: What is the process used by OSPF to build a routing table (step by step)
Interface changes state (up/down) - A route has entered or exited the unreachable state - a route was installed in the routing table.
14 per network
2 - each port is it's own collision domain
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database

24. OSPF: What does OSPF use for its metric?
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)
30 per network
The metric is called cost - and refers to the speed of the port - IE 56kps = 1785 where Fast Ethernet = 1

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

26. What is Layer 6 in the OSI Model?
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)
Switch forwards the frame as soon as it can
Presentation
255.255.0.0

27. What is the boot sequence for Cisco Routers?
Packets
Switch forwards frame once it completely receives it
60
1. NVRAM - 2. Flash (sequential) - 3. TFTP server (network boot) - 4. ROM (partial IOS)

28. Subnetting: How many hosts per network if the subnet mask is 255.255.255.128
Every 4 ip's
Bellman-Ford
Network
126 per network

29. IEEE Standards: Fast Ethernet
Shortest path first - (SPF)
Closest multiple of the magic number that is not over the interesting octets number.
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
IEEE 802.3u

30. How many Collision domains are there on a with 1 hub and 2 computers?
255.255.0.0
1 - everything hooked to the hub is in the same collision domain
IEEE 802.3z
R1(config)#int s0/0 - R1(config-inf)clock rate 64000 <-- on the DCE

31. EIGRP: How do you view if there are any successor routes?
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
Hop Count
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
Show ip eigrp topology

32. What is Layer 5 in the OSI Model?
255.255.0.0
Session
DUAL: Difusing Update Algorithm
Data-Link

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

34. Subnetting: How many hosts per network if the subnet mask is 255.255.255.192
Transport
Data-Link
Hop Count
62 per network

35. What is the layer 4 PDU called?
Segments
126 per network
1:G/W - 2:Green - 3:O/W - 4:Blue - 5:B/W - 6:Orange - 7:Brown/W - 8:Brown
IEEE 802.3z

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

37. Rip Timers: How long is the default for Invalid timer.
255.255.192.0
1-65535
180 seconds
Multicast packet used for discovery of neighbors sent every 5 seconds - on WAN links sent every 60 seconds

38. What is the Transport PDU called?
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical
Can be multicast or unicast depending on number of routers - Update packets. Responds with an ACK packet
Segments
255.255.255.252

39. RIP: Commands to enable ripv1 on a router and add a route to 192.168.1.2
R1(config)#router eigrp 7 - R1(config-router)#network 192.168.1.0 0.0.0.3
Router(config)#ip route {network address} {subnet-mask}
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

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

41. RIP Timers: What is an invalid 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
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.
Bandwidth - Delay - reliability and Load

42. Switching Methods: What is Cut-through?
Switch forwards the frame as soon as it can
Hop Count
IEEE 802.3
R

43. Subnetting: How many hosts per network if the subnet mask is 255.255.255.240
Packets
14 per network
IEEE 802.3ab
IEEE 802.3z

44. Switching Methods: What is Fragment-free?
Can be multicast or unicast depending on number of routers - Update packets. Responds with an ACK packet
Switch forwards frame after receiving the 1st 64bytes to insure no errors.
Pins 1+2 swap places with pins 3+6
DCE

45. Using the magic number how to you figure the broadcast?
1. Discovery packets - LSP built containing the state of each link - Flood LSP to neighbors - Build Link-state database
Add the magic number to the network minus 1
R1(config)#int s0/0 - R1(config-inf)clock rate 64000 <-- on the DCE
Packets

46. How do you find the magic number for subnetting?
255.255.192.0
Use command bandwidth {bandwidth in KPS} or the command ip ospf cost {amount} both in the interface you want to change
256 - the interesting (non-255/0) number. IE: 255.240.0.0 the interesting number is 240
Can be multicast or unicast depending on number of routers - Update packets. Responds with an ACK packet

47. Subnetting: What is a /27 in Decimal
Every 16 ip's
255.255.255.224
2 hosts
(5)Application - (4)Transport - (3)Internet - (2)Data-Link - (1)Physical

48. IEEE Standards: Gibabit Ethernet (Copper)
R1(config)#int s0/0 - R1(config-inf)clock rate 64000 <-- on the DCE
Every 16 ip's
IEEE 802.3ab
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

49. 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
Query and other router responds with a REPLY packet.
(7)Application -(6)Presentation -(5)Session -(4)Transport - (3)Network - (2)Data Link - (1)Physical
Session

50. Rip: how do hold down timers work?
/9
Every 64 ip's
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