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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. Displays error-disabled detection status
Switch#show errdisable detect
The Punt adjacency
10 km
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

2. What are the symptoms of a duplex setting mismatch between two ends of a link?
Switch#show errdisable recovery
40 km
100 metres
Slow response times - low throughput - runts and other input errors on the switch ports

3. Changes an interface to a layer 3 interface and erases all layer 2 interface configurations
Switch#show errdisable detect
Cabling specifications for Gigabit Ethernet
Switch(config-if)#no switchport
Store-and-forward

4. What is the administrative mode of a switch port that uses DTP to negotiate its operational mode?
Dynamic
Switch(config-if)#switchport mode access
IEEE 802.3z
Numeric values that represent what action to take after the TCAM lookup occurs

5. Enables error-disable for errors with offering inline power
Switch(config-if)#description {string}
Switch(config)#errdisable detect cause ilpower
Off
10 Gigabit Ethernet over copper CX4 with Infiniband connectors

6. Enables error-disable for errors when assigning a port to a dynamic VLAN through a VMPS
Security and QoS ACLs
Switch(config)#default interface {interface}
Switch(config)#errdisable detect cause vmps
Switch(config-if)#duplex {auto | full | half}

7. Sets the duplex mode of an Ethernet or Fast Ethernet interface
On
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
When one station transmits at the same time as another on a shared medium
Switch(config-if)#duplex {auto | full | half}

8. Displays static CAM table entries
Switch(config)#errdisable detect cause bpduguard
R = LAN PHY; W = WAN PHY
25 metres
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]

9. Selects a switch port interface and enters interface configuration mode
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
Switch(config)#interface {type}{module}/{number}
Switch#show adjacency [{interface}] [summary | detail]
SVI

10. Displays the CAM table size with number of MAC addresses
Source MAC address; Port of arrival; VLAN; Time stamp
Trunk or dynamic
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]

11. What CEF adjacency is used to discard packets because of access list or other policy action?
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Switch(config-if)#switchport access vlan {vlan}
The Discard adjacency
Switch#show interfaces status err-disabled

12. What is the content of TCAM Result entries?
The Layer 3 engine
Numeric values that represent what action to take after the TCAM lookup occurs
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
LAN PHY and WAN PHY

13. What is a SVI?
The CEF epoch number
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
Switched virtual interface (SVI)
100 metres

14. What two IOS software components are involved in TCAM operation?
Feature Manager (FM) and Switching Database Manager (SDM)
Switch(config)#errdisable recovery interval {seconds}
Interconnecting switches in a campus network
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance

15. What is the timer range for automatic re-enabling of error-disabled ports?
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
From 30 seconds to 86 -400 seconds (24 hours)
Switch(config)#errdisable detect cause channel-misconfig
IEEE 802.3z

16. What is ANSI?
Switch(config)#errdisable detect cause vmps
American National Standards Institute
When one station transmits at the same time as another on a shared medium
1000BASE-T full duplex followed by 1000BASE-T half duplex

17. What is a GigaStack GBIC?
Off
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)

18. What is 10GBASE-LR/LW?
Manually by administratively disabling and re-enabling the port
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
CEF glean
By electrical signalling so that either end of a link can determine what speed the other end is trying to use

19. What is a ternary combination?

20. What RJ-45 pins must be swapped in a Category 5 UTP crossover cable for Gigabit Ethernet?
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
Store-and-forward
Content-Addressable Memory
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]

21. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Only temporarily for debugging purposes
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
ANSI X3T11 FibreChannel
Switch(config)#errdisable detect cause l2ptguard

22. What is CEF?
Ternary Content-Addressable Memory
They are dropped (ARP throttling)
Cisco Express Forwarding
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX

23. Sets the administrative mode of a switch port to access
Switch(config)#errdisable detect cause gbic-invalid
Native routed interface
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(config-if)#switchport mode access

24. What changes are made to packets by the CEF packet rewrite engine just before forwarding?
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
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
The Discard adjacency
From 30 seconds to 86 -400 seconds (24 hours)

25. What is the maximum cabling distance for Fast Ethernet over 62.5/125 micron multimode fibre?
By Mask/Value - where each unique mask has eight value patterns associated with it
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Switch(config-if)#description {string}
400 metres half duplex and 2000 metres full duplex

26. What are the administrative modes of Layer 2 switched interfaces?
Static access - trunk - tunnel or dynamic
1000BASE-T full duplex followed by 1000BASE-T half duplex
Switch(config)#errdisable detect cause l2ptguard
Switch(config-if)#description {string}

27. What is 10GBASE-CX4?
Logical Operation Unit
Switch(config)#errdisable recovery cause {all | {cause-name}}
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
10 Gigabit Ethernet over copper CX4 with Infiniband connectors

28. Removes entries from the CAM table
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Full duplex
Switch(config)#interface vlan {vlan-id}

29. What is 100BASE-FX?
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Switch(config-if)#no switchport
Switch(config-if)#duplex {auto | full | half}
Switch(config)#errdisable detect cause ilpower

30. Enables error-disable when an interface has been looped back
300 seconds
The switch port falls back to default setting of half duplex
Switch(config)#errdisable detect cause l2ptguard
Switch(config)#errdisable detect cause loopback

31. What is the standard for 10 Gigabit Ethernet (10GbE)?
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
IEEE 802.3ae
Enable error-disable for all possible causes

32. What CEF adjacency is used to switch packets that can't be forwarded normally?
Switch(config)#errdisable detect cause {all | {cause-name}}
The Drop adjacency
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
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

33. What is the default duplex mode of a Gigabit Ethernet interface?
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Content-Addressable Memory
Full duplex

34. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
On
The Punt adjacency
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

35. What is the original standard for Ethernet (10 Mbps)?
Dynamic
Native routed interface
IEEE 802.3
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]

36. What combinations are TCAM entries composed of?
Value - Mask - and Result (VMR)
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP

37. What is 100BASE-T2?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Security and QoS ACLs

38. What are the names of CEF optimisation techniques using specialised forwarding hardware?
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
10 km
Wide-Wavelength Division Multiplexing

39. What is the maximum cabling distance for 10GBASE-ER/EW?
40 km
Switch(config)#errdisable detect cause channel-misconfig
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
When one station transmits at the same time as another on a shared medium

40. What are the letters used with 10GBASE-X two-letter suffixes to specify the PHY type?
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)
Full duplex only
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
R = LAN PHY; W = WAN PHY

41. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Switch#show ip cef {interface} [detail]
The Punt adjacency
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
A station must wait its turn to transmit; it can't transmit and receive at the same time

42. What are the reasons for packets being punted by CEF?
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
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Trunk or dynamic
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

43. What is the DTP negotiation mode of a switch port configured as dynamic?
On
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
LOU registers

44. What is the operational mode of a switch port that carries traffic for multiple VLANs?
ARP requests and replies; IP packets requiring an ICMP response; IP broadcasts to be relayed; Routing protocol updates; CDP packets; Packets needing encryption; Packets triggering NAT; Other non-IP packets
Trunk
Switch(config-if)#shutdown
Switch(config)#errdisable recovery cause {all | {cause-name}}

45. What are the basic operations that a frame undergoes as it passes through a multilayer switch?
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Ternary Content-Addressable Memory
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
70 km for 9 micron SMF; 100 km for 8 micron SMF

46. What CEF optimisation technique cache FIB entries in switch line cards?
Route caching and topology based
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
Accelerated CEF (aCEF)
Full duplex only

47. What is WAN PHY used for?
S = Short; L = Long; E = Extra-long
Tunnel
Full duplex
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks

48. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
Switch#show adjacency [{interface}] [summary | detail]
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Only temporarily for debugging purposes
10 km

49. Enables error-disable when the Port Aggregation Protocol (PAgP) is flapping
1000BASE-T full duplex followed by 1000BASE-T half duplex
Switch(config)#errdisable detect cause pagp-flap
On
Full duplex only

50. What is EMI?
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
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
Electromagnetic Interference
When one station transmits at the same time as another on a shared medium