Test your basic knowledge |

Ethernet Technologies

Subject : it-skills

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. What fields are rewritten in hardware before a Layer 3 packet is switched to the to egress queue of a multilayer switch?
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Source MAC address; Port of arrival; VLAN; Time stamp
Static access
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum

2. Enables error-disable for rate-limiting of DHCP snooping
IEEE 802.3
Switch(config)#errdisable detect cause dhcp-rate-limit
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
1000BASE-T full duplex followed by 1000BASE-T half duplex

3. What technology was merged into the IEEE 802.3 Ethernet standard to create Gigabit Ethernet?
Switch(config)#errdisable detect cause arp-inspection
ANSI X3T11 FibreChannel
10 km
The Null adjacency

4. What are the Fast Ethernet autonegotiation selection priorities?
Switch#show ip cef
A station must wait its turn to transmit; it can't transmit and receive at the same time
SVI or native routed interface
7 100BASE-T2 full duplex; 6 100BASE-TX full duplex; 5 100BASE-T2 half duplex; 4 100BASE-T4; 3 100BASE-TX; 2 10BASE-T full duplex; 1 10BASE-T

5. Creates an interface-range macro
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
IEEE 802.3u
The Drop adjacency
Switch(config-if)#duplex {auto | full | half}

6. What is the administrative mode of a switch port that carries transparent Layer 2 VPNs?
Switch(config)#mac address-table aging-time {seconds}
Tunnel
SVI or native routed interface
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]

7. Sets the administrative mode of a switch port to access
Entry not in FIB; FIB table full; IP TTL expired; MTU exceeded; ICMP redirect; Unsupported encapsulation; Tunnelled packets requiring compression or encryption; Access list with 'log' option; NAT must be performed
1000BASE-T full duplex followed by 1000BASE-T half duplex
Switch(config-if)#switchport mode access
The switch port falls back to default setting of half duplex

8. Adds a static entry to the MAC address table
Switch(config)#errdisable detect cause link-flap
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
When one station transmits at the same time as another on a shared medium

9. Displays dynamic CAM table entries
R = LAN PHY; W = WAN PHY
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
15 metres
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]

10. What is LOU?
Layer 2 destination address changed to next-hop MAC address; Layer 2 source address changed to outbound interface MAC address; Layer 3 TTL decremented by 1; Layer 3 IP checksum recalculated; Layer 2 frame checksum recalculated
Switch#show interfaces {interface} switchport
Logical Operation Unit
Switch#show ip cef

11. What is the administrative mode of a switch port that is a member of one VLAN?
Static access or dynamic
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Switch#show errdisable detect

12. Displays CEF Drop statistics with number of packets and reason for each line card
Switch#show cef drop
SVI
Switch(config)#errdisable detect cause l2ptguard
American National Standards Institute

13. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
Only temporarily for debugging purposes
Switch(config)#errdisable detect cause channel-misconfig
They are dropped (ARP throttling)
10 km

14. Changes an interface to a layer 3 interface and erases all layer 2 interface configurations
100 metres
They are dropped (ARP throttling)
Trunk
Switch(config-if)#no switchport

15. How are ternary combinations implemented?
With a mask value in addition to binary values to decide which keys in a table are relevant
The Layer 3 engine
Switch(config)#errdisable detect cause rootguard
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries

16. What are the names of CEF optimisation techniques using specialised forwarding hardware?
Creating the VLAN
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Half duplex
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself

17. How are packets marked before being sent to the CEF Layer 3 engine for further processing?
CEF punt
IEEE 802.3u
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

18. What are the types of layer 3 switched interfaces
Forwarding Information Base
SVI or native routed interface
Switch(config)#errdisable detect cause storm-control
IEEE 802.3u

19. What is LAN PHY used for?
LC - MT-RJ or RJ-45
7 100BASE-T2 full duplex; 6 100BASE-TX full duplex; 5 100BASE-T2 half duplex; 4 100BASE-T4; 3 100BASE-TX; 2 10BASE-T full duplex; 1 10BASE-T
Interconnecting switches in a campus network
Full duplex only

20. What are the symptoms of a duplex setting mismatch between two ends of a link?
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Slow response times - low throughput - runts and other input errors on the switch ports
Route caching and topology based
Switch(config)#interface vlan {vlan-id}

21. Displays the contents of the CAM table
Cabling specifications for Gigabit Ethernet
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause loopback
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum

22. What tables are maintained by the CEF Layer 3 engine?
American National Standards Institute
Routing table and ARP table
IEEE 802.3ab
LC - MT-RJ or RJ-45

23. How are the TCAM Mask/Value pairs evaluated?
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
Forwarding Information Base
In parallel revealing the best (longest) match in a single table lookup
Switch(config-if)#duplex {auto | full | half}

24. Enables error-disable detection
40 km
Switch(config)#errdisable detect cause {all | {cause-name}}
Feature Manager (FM) and Switching Database Manager (SDM)
Ternary Content-Addressable Memory

25. Displays CEF adjacency table information
Interconnecting switches in a campus network
70 km for 9 micron SMF; 100 km for 8 micron SMF
Switch#show adjacency [{interface}] [summary | detail]
Electromagnetic Interference

26. How does the IEEE 802.3ae standard differ from its predecessors at the physical layer?
10 km
10GbE operates only at full duplex
American National Standards Institute
A three-fold combination of 0 - 1 and X (don't care)

27. What are the duplex modes of a GigaStack GBIC?
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
Switch(config-if)#no switchport
A three-fold combination of 0 - 1 and X (don't care)
Enable error-disable for all possible causes

28. What is 100BASE-T4?
Half duplex
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Routing table and ARP table

29. What is the operational mode of a switch port that is a member of one VLAN?
Switch(config)#errdisable recovery cause {all | {cause-name}}
Static access
In TCAM Value entries
Incomplete adjacency; Incomplete ARP resolution; Unsupported packet features; ICMP redirect; Packets destined to the router itself; IP options present; Access list evaluation failure; Fragmentation failure

30. What is CEF?
Cisco Express Forwarding
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP

31. What is 1000BASE-T?
Switch(config)#errdisable detect cause link-flap
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
The CEF entry version number

32. Sets the speed of a Fast Ethernet or Gigabit Ethernet interface
Switch(config-if)#speed {10 | 100 | 1000 | auto}
When one station transmits at the same time as another on a shared medium
70 km for 9 micron SMF; 100 km for 8 micron SMF
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding

33. Displays a list with status of all interfaces
Routing table and ARP table
Collision domain
Numeric values that represent what action to take after the TCAM lookup occurs
Switch#show interfaces status

34. What are the administrative modes of Layer 2 switched interfaces?
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Static access - trunk - tunnel or dynamic
With a mask value in addition to binary values to decide which keys in a table are relevant
Switch(config)#default interface {interface}

35. What CEF optimisation technique cache FIB entries in switch line cards?
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
The Null adjacency
Accelerated CEF (aCEF)
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

36. Selects an interface-range macro and enters interface configuration mode
10 km
In TCAM Value entries
A station must wait its turn to transmit; it can't transmit and receive at the same time
Switch(config)#interface range macro {name}

37. What is the maximum cabling distance for 10GBASE-SR/SW?
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF
Static access or trunk
Native routed interface

38. What is the operational mode of a switch port that carries traffic for multiple VLANs?
Trunk
Switch(config)#interface {type}{module}/{number}
Accelerated CEF (aCEF)
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling

39. What is 10GBASE-ER/EW?
SC fibre optic or RJ-45 UTP
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
Switch(config)#errdisable detect cause dtp-flap
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]

40. What CEF adjacency is used to switch packets destined for the null interface?
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Switch(config)#errdisable detect cause gbic-invalid
Half duplex
The Null adjacency

41. What is the content of TCAM Mask entries?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

42. What is 100BASE-FX?
Switch(config)#errdisable detect cause unicast-flood
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
IEEE 802.3z

43. What is the default timer for automatic re-enabling of error-disabled ports?
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
300 seconds
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks

44. When do collisions occur?
Static access - trunk - tunnel or dynamic
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
Switch#show interfaces status err-disabled
When one station transmits at the same time as another on a shared medium

45. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
The Punt adjacency
Manually by administratively disabling and re-enabling the port
SC or MT-RJ
A switch port that has been shut down automatically due to a serious error condition

46. Enables error-disable for when the port link state is flapping between the up and down states
Full duplex
Switch(config)#errdisable detect cause link-flap
Switch(config)#errdisable recovery interval {seconds}
SC fibre optic or RJ-45 UTP

47. Enables error-disable for errors with dynamic ARP inspection
Switch(config)#errdisable detect cause arp-inspection
Switched virtual interface (SVI)
SC fibre optic or RJ-45 UTP
Switch(config)#errdisable detect cause ilpower

48. What are the basic operations that a frame undergoes as it passes through a Layer 2 switch?
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Switch(config-if)#description {string}
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4

49. What is TCAM?
Packets that have been truncated before they were fully received
With a mask value in addition to binary values to decide which keys in a table are relevant
Ternary Content-Addressable Memory
LAN PHY and WAN PHY

50. What is WWDM?
40 km
Switch(config-if)#shutdown
Wide-Wavelength Division Multiplexing
IEEE 802.3ab