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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 is a GigaStack GBIC?
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
Switch(config-if)#switchport access vlan {vlan}
Switch(config)#errdisable detect cause unicast-flood

2. Enables error-disable when an STP BPDU is received from a root bridge on an unexpected port
Enable error-disable for all possible causes
Switch(config)#errdisable detect cause rootguard
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
S = Short; L = Long; E = Extra-long

3. What is 10BASE-T?
10 km
Trunk or dynamic
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)

4. What are runts?
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
Source MAC address; Port of arrival; VLAN; Time stamp
Packets that have been truncated before they were fully received

5. What is the state of packets that are sent to the CEF Layer 3 engine because of missing Layer 2 next-hop addresses?
Electromagnetic Interference
CEF glean
Wide-Wavelength Division Multiplexing
Source MAC address; Port of arrival; VLAN; Time stamp

6. What are the Fast Ethernet autonegotiation selection priorities?
Switch(config)#interface range macro {name}
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Source MAC address; Port of arrival; VLAN; Time stamp
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

7. What are the Gigabit Ethernet autonegotiation selection priorities?
Compiling Access Control Entries (ACE) into the TCAM table
1000BASE-T full duplex followed by 1000BASE-T half duplex
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP

8. What are the duplex modes of a GigaStack GBIC?
Creating the VLAN
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
Distributed CEF (dCEF)
Switch(config-if)#description {string}

9. What is a ternary combination?

10. What CEF adjacency is used to discard packets because of access list or other policy action?
10GbE operates only at full duplex
FIB with adjacency table
A name assigned to a ranges of interfaces
The Discard adjacency

11. Enables error-disable for errors with offering inline power
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch(config)#default interface {interface}
Switch(config)#errdisable detect cause ilpower
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP

12. What is error-disable state?
A switch port that has been shut down automatically due to a serious error condition
Compiling Access Control Entries (ACE) into the TCAM table
Switch(config)#mac address-table aging-time {seconds}
Switch#show ip cef

13. Displays error-disabled detection status
With MMF cables shorter than 100 metres (to prevent over-driving the far-end receiver) and with MMF cables longer than 300 metres (to lessen the effect of differential mode delay)
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#show errdisable detect
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

14. How is the TCAM organised?
Source MAC address; Port of arrival; VLAN; Time stamp
By Mask/Value - where each unique mask has eight value patterns associated with it
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Down - static access - trunk or tunnel

15. What is the name of physical network segment where data packets can collide with one another when being sent?
1 -2 on one end with 3 -6 on the other end - and 4 -5 on one end with 7 -8 on the other end
XENPAK - X2 - or SFP+
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
Collision domain

16. What tables are maintained by the CEF Layer 3 engine?
Routing table and ARP table
The switch port falls back to default setting of half duplex
Multilayer Switching
Switch(config)#errdisable recovery cause {all | {cause-name}}

17. What combinations are TCAM entries composed of?
Switch(config-if)#no switchport
Value - Mask - and Result (VMR)
Cisco Express Forwarding
Source MAC (/48); Destination MAC (/48); Ethertype (/16)

18. What is the TCAM Value and Mask for an IP access list?
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Security and QoS ACLs
A switch port that has been shut down automatically due to a serious error condition

19. What is 100BASE-TX?
Static access or dynamic
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Route caching and topology based

20. What is 1000BASE-ZX?
Carrier Sense Multiple Access Collision Detection
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Static access - trunk - tunnel or dynamic
Switch(config-if)#switchport mode access

21. Displays a list with status of all interfaces
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Tunnel
70 km for 9 micron SMF; 100 km for 8 micron SMF
Switch#show interfaces status

22. Removes entries from the CAM table
Ternary Content-Addressable Memory
SC or MT-RJ
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]

23. What is CEF?
100 metres
The Drop adjacency
The Discard adjacency
Cisco Express Forwarding

24. Displays dynamic CAM table entries
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
1 -2 on one end with 3 -6 on the other end - and 4 -5 on one end with 7 -8 on the other end
Switch(config)#interface range macro {name}
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance

25. Displays CEF Punt statistics with number of packets and reason for each line card
Compiling Access Control Entries (ACE) into the TCAM table
Native routed interface
Switch#show cef not-cef-switched
Logical Operation Unit

26. Selects multiple switch port interfaces at the same time and enters interface configuration mode
Switch(config)#mac address-table aging-time {seconds}
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4

27. Creates a switched virtual interface (SVI) and enters interface configuration mode
Switch(config)#interface vlan {vlan-id}
Full duplex
When one station transmits at the same time as another on a shared medium
S = Short; L = Long; E = Extra-long

28. How are ternary combinations implemented?
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
With a mask value in addition to binary values to decide which keys in a table are relevant
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
In parallel revealing the best (longest) match in a single table lookup

29. What is 10GBASE-LR/LW?
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
IEEE 802.3ae
Switch(config)#errdisable detect cause loopback
Switch(config)#errdisable detect cause unicast-flood

30. What is 100BASE-T2?
10 km
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Switch(config)#errdisable detect cause gbic-invalid
In TCAM Value entries

31. Displays the entire Forwarding Information Base (FIB)
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Switch#show ip cef
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum

32. What are the classes of Physical Media Dependent (PMD) interfaces defined by IEEE 802.3ae?
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
The Drop adjacency
LAN PHY and WAN PHY
They are dropped (ARP throttling)

33. What CEF adjacency is used to switch packets destined for the null interface?
Switch(config)#errdisable detect cause link-flap
Switch(config)#interface {type}{module}/{number}
The Null adjacency
SC fibre optic or RJ-45 UTP

34. What is the name of the CEF engine that maintains routing information in software?
The Layer 3 engine
Switch(config)#no ip cef
SVI or native routed interface
A switch port that has been shut down automatically due to a serious error condition

35. How is link speed determined on Fast Ethernet links configured to autonegotiate?
70 km for 9 micron SMF; 100 km for 8 micron SMF
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
CEF punt
A station must wait its turn to transmit; it can't transmit and receive at the same time

36. What function is performed by the Feature Manager (FM)?
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
Only temporarily for debugging purposes
Compiling Access Control Entries (ACE) into the TCAM table

37. What is a SVI?
When one station transmits at the same time as another on a shared medium
Switched virtual interface (SVI)
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Value - Mask - and Result (VMR)

38. What is the timer range for automatic re-enabling of error-disabled ports?
From 30 seconds to 86 -400 seconds (24 hours)
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)
LAN PHY and WAN PHY
Distributed CEF (dCEF)

39. When do collisions occur?
When one station transmits at the same time as another on a shared medium
Half duplex
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

40. Enables error-disable for when the port link state is flapping between the up and down states
IEEE 802.3z
Compiling Access Control Entries (ACE) into the TCAM table
Forwarding Information Base
Switch(config)#errdisable detect cause link-flap

41. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
Switch#show errdisable recovery
The Punt adjacency
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks

42. What is 10GBASE-LX4/LW4?
Ternary Content-Addressable Memory
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Switch(config-if)#switchport access vlan {vlan}
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)

43. What is CAM?
The adjacency table
Content-Addressable Memory
Route caching and topology based
By Mask/Value - where each unique mask has eight value patterns associated with it

44. Enables error-disable for errors when assigning a port to a dynamic VLAN through a VMPS
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
Switch#show errdisable recovery
Switch(config)#errdisable detect cause vmps
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)

45. Displays interface configuration information
Switch#show running-config interface {interface}
Slow response times - low throughput - runts and other input errors on the switch ports
40 km
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum

46. What mechanism does the TCAM provide for Layer 4 comparisons involving gt - lt - neq or range operators?
Switch(config)#interface vlan {vlan-id}
Switch(config)#errdisable detect cause psecure-violation
With MMF cables shorter than 100 metres (to prevent over-driving the far-end receiver) and with MMF cables longer than 300 metres (to lessen the effect of differential mode delay)
LOU registers

47. Enables error-disable for conditions that trigger port security configured on a port
Switch(config)#errdisable detect cause psecure-violation
The Drop adjacency
On
The Layer 3 forwarding engine

48. Enables error-disable for errors related to 802.1x security
Enable error-disable for all possible causes
Switch(config)#errdisable detect cause security-violation
Tunnel
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)

49. What are the symptoms of a duplex setting mismatch between two ends of a link?
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
Slow response times - low throughput - runts and other input errors on the switch ports
300 seconds
On

50. What is the standard for Fast Ethernet (100 Mbps)?
10GbE operates only at full duplex
Forwarding Information Base
IEEE 802.3u
Switch(config)#default interface {interface}