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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 the role of a Route Processor (RP) in first generation MLS?
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Process the first packet in a traffic flow to determine the destination
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Tunnel

2. What are the common cabling specifications for Gigabit Ethernet?
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
The table of learned MAC addresses - ports - and VLAN information
Static access or trunk
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX

3. What are the symptoms of a duplex setting mismatch between two ends of a link?
Switch(config)#errdisable detect cause storm-control
Slow response times - low throughput - runts and other input errors on the switch ports
IEEE 802.3z
Store-and-forward

4. What information is stored in CAM?
Static access or trunk
The adjacency table
The table of learned MAC addresses - ports - and VLAN information
Dynamic

5. What is MLS?
Multilayer Switching
Switch(config)#mac address-table aging-time {seconds}
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
A name assigned to a ranges of interfaces

6. Adds a static entry to the MAC address table
A name assigned to a ranges of interfaces
Static access - trunk - tunnel or dynamic
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}

7. What are the common cabling specifications for Fast Ethernet?
Switch#show cef not-cef-switched
300 seconds
Off
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

8. What is the default timer for automatic re-enabling of error-disabled ports?
When one station transmits at the same time as another on a shared medium
Switch(config)#no ip cef
300 seconds
Half duplex

9. Sets the duplex mode of an Ethernet or Fast Ethernet interface
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Switch(config-if)#duplex {auto | full | half}
10GbE operates only at full duplex

10. What is the maximum cabling distance for 10GBASE-LR/LW?
10GbE operates only at full duplex
1000BASE-T full duplex followed by 1000BASE-T half duplex
10 km
CEF punt

11. What is FIB?
Forwarding Information Base
Full duplex only
The CEF entry version number
10 km

12. What is Fast EtherChannel (FEC)?
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Switch(config)#errdisable detect cause storm-control
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Source MAC (/48); Destination MAC (/48); Ethertype (/16)

13. Displays a list with status of all interfaces
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
Switch#show interfaces status
The table of learned MAC addresses - ports - and VLAN information
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)

14. How are ports that are in error-disable state re-enabled by default?
Routing table and ARP table
Manually by administratively disabling and re-enabling the port
Partition and tune the TCAM on some Catalyst switches into areas for different functions
On

15. What fields are rewritten in hardware before a Layer 3 packet is switched to the to egress queue of a multilayer switch?
The Layer 3 forwarding engine
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
IEEE 802.3ab
Trunk

16. How is link speed determined on Fast Ethernet links configured to autonegotiate?
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF
Switch(config)#interface {type}{module}/{number}
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
On

17. What is LAN PHY used for?
Switch(config)#errdisable detect cause storm-control
Interconnecting switches in a campus network
LOU registers
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]

18. Enables error-disable for errors with offering inline power
Switch(config)#errdisable detect cause ilpower
Cabling specifications for 10 Gigabit Ethernet
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Compiling Access Control Entries (ACE) into the TCAM table

19. What is the maximum cabling distance for 1000BASE-SX?
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF

20. Enables error-disable for rate-limiting of DHCP snooping
Switch(config)#errdisable detect cause vmps
Switch(config)#errdisable detect cause pagp-flap
Switch(config)#errdisable detect cause dhcp-rate-limit
The table of learned MAC addresses - ports - and VLAN information

21. Creates a switched virtual interface (SVI) and enters interface configuration mode
25 metres
A three-fold combination of 0 - 1 and X (don't care)
Switch(config)#interface vlan {vlan-id}
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)

22. Displays entries in the Forwarding Information Base (FIB) for a specific interface
LC - MT-RJ or RJ-45
Route caching and topology based
Switch#show ip cef {interface} [detail]
A station must wait its turn to transmit; it can't transmit and receive at the same time

23. When should CEF be disabled?
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Only temporarily for debugging purposes
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
70 km for 9 micron SMF; 100 km for 8 micron SMF

24. What are the letters used with 10GBASE-X two-letter suffixes to specify the PHY type?
Compiling Access Control Entries (ACE) into the TCAM table
R = LAN PHY; W = WAN PHY
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Switch(config)#errdisable detect cause pagp-flap

25. What is the name of the CEF engine that maintains routing information in software?
In TCAM Value entries
LOU registers
The Layer 3 engine
SVI or native routed interface

26. What two IOS software components are involved in TCAM operation?
10 km
Collision domain
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Feature Manager (FM) and Switching Database Manager (SDM)

27. What is 1000BASE-LX/LH?
Switch(config)#errdisable detect cause link-flap
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
Switch(config-if)#no switchport

28. What are the supported duplex mode settings for Gigabit Ethernet on Cisco switches?
Store-and-forward
Content-Addressable Memory
Switch(config)#errdisable detect cause storm-control
Full duplex only

29. What happens when autonegotiating of link duplex mode fails on a Fast Ethernet link?
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)
Collision domain
The switch port falls back to default setting of half duplex
Switch(config-if)#description {string}

30. Enables error-disable when the Port Aggregation Protocol (PAgP) is flapping
Electromagnetic Interference
Only temporarily for debugging purposes
Switch(config)#errdisable detect cause pagp-flap
SVI or native routed interface

31. What is the administrative mode of a switch port that carries transparent Layer 2 VPNs?
Tunnel
Switch#show cef not-cef-switched
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

32. What is CAM?
They are dropped (ARP throttling)
Content-Addressable Memory
LAN PHY and WAN PHY
Source MAC address; Port of arrival; VLAN; Time stamp

33. What is the name of a Layer 3 physical interface on a switch?
FIB with adjacency table
Switch(config)#interface range macro {name}
Native routed interface
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)

34. What is 10BASE-T?
Compiling Access Control Entries (ACE) into the TCAM table
Layer 3 routing information builds and pre-populates a single database of the entire network topology; All table lookups are performed in hardware with the longest matching destination used in forwarding
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Switched virtual interface (SVI)

35. What is TCAM overflow?
Forwarding Information Base
IEEE 802.3ab
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Manually by administratively disabling and re-enabling the port

36. Sets the speed of a Fast Ethernet or Gigabit Ethernet interface
Switch(config-if)#speed {10 | 100 | 1000 | auto}
LOU registers
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)
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)

37. What is 1000BASE-ZX?
Switch(config)#errdisable detect cause vmps
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding

38. Specifies the timer for automatic re-enabling of error-disabled ports
Switch(config)#errdisable recovery interval {seconds}
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
40 km
Static access or dynamic

39. Displays a list of all interfaces in an error-disabled state
Full duplex
Switch#show interfaces status err-disabled
Process the first packet in a traffic flow to determine the destination
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4

40. What is 10GBASE-ER/EW?
Static access - trunk - tunnel or dynamic
Feature Manager (FM) and Switching Database Manager (SDM)
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
SC or MT-RJ

41. What are the names of the two basic generations of MLS?
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
Compiling Access Control Entries (ACE) into the TCAM table
Route caching and topology based
The Layer 3 forwarding engine

42. What is the default duplex mode of a Gigabit Ethernet interface?
When one station transmits at the same time as another on a shared medium
Full duplex
Interconnecting switches in a campus network
LC - MT-RJ or RJ-45

43. What is the standard for Fast Ethernet (100 Mbps)?
Switch(config-if)#duplex {auto | full | half}
American National Standards Institute
Trunk or dynamic
IEEE 802.3u

44. What is error-disable state?
Switch(config)#errdisable detect cause rootguard
Accelerated CEF (aCEF)
A switch port that has been shut down automatically due to a serious error condition
Switch(config)#errdisable detect cause bpduguard

45. What denotes the number of times a CEF entry has been updated since the CEF table was created?
Off
The CEF entry version number
R = LAN PHY; W = WAN PHY
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX

46. What is 10GBASE-SR/SW?
Switch(config-if)#switchport mode access
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
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
Switch(config-if)#shutdown

47. What function is performed by the Feature Manager (FM)?
The Drop adjacency
Compiling Access Control Entries (ACE) into the TCAM table
Security and QoS ACLs
Only temporarily for debugging purposes

48. What are the names of CEF optimisation techniques using specialised forwarding hardware?
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
Switch(config)#errdisable detect cause link-flap
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

49. What combinations are TCAM entries composed of?
Value - Mask - and Result (VMR)
SC or MT-RJ
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP

50. Enables error-disable detection
IEEE 802.3
Switch(config)#interface {type}{module}/{number}
Switch(config)#no ip cef
Switch(config)#errdisable detect cause {all | {cause-name}}