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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. Disables a switch port
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
Switch(config-if)#shutdown
1 -2 on one end with 3 -6 on the other end
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)

2. What is the administrative mode of a switch port that is a member of one VLAN?
Interconnecting switches in a campus network
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
Compiling Access Control Entries (ACE) into the TCAM table
Static access or dynamic

3. How are ternary combinations implemented?
With a mask value in addition to binary values to decide which keys in a table are relevant
Switch(config)#errdisable detect cause {all | {cause-name}}
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
400 metres half duplex and 2000 metres full duplex

4. What happens when autonegotiating of link duplex mode fails on a Fast Ethernet link?
The switch port falls back to default setting of half duplex
Switch(config)#default interface {interface}
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
With a mask value in addition to binary values to decide which keys in a table are relevant

5. What is the timer range for automatic re-enabling of error-disabled ports?
1 -2 on one end with 3 -6 on the other end
From 30 seconds to 86 -400 seconds (24 hours)
Switch(config)#errdisable recovery interval {seconds}
1000BASE-T full duplex followed by 1000BASE-T half duplex

6. What is Fast EtherChannel (FEC)?
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
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
Switch(config)#errdisable recovery interval {seconds}
Switch(config)#errdisable detect cause gbic-invalid

7. Sets the speed of a Fast Ethernet or Gigabit Ethernet interface
Switch(config-if)#speed {10 | 100 | 1000 | auto}
Full duplex only
XENPAK - X2 - or SFP+
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF

8. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
R = LAN PHY; W = WAN PHY
10 km
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

9. When should CEF be disabled?
Static access
Only temporarily for debugging purposes
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)
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. What CEF adjacency is used to switch packets destined for the null interface?
The Null adjacency
Static access or trunk
American National Standards Institute
Switch(config)#errdisable detect cause bpduguard

11. What is the TCAM Value and Mask for an IP access list?
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
With a mask value in addition to binary values to decide which keys in a table are relevant
R = LAN PHY; W = WAN PHY
Cabling specifications for 10 Gigabit Ethernet

12. What is the operational mode of a switch port that carries transparent Layer 2 VPNs?
Tunnel
IEEE 802.3z
American National Standards Institute
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)

13. Enables error-disable for rate-limiting of DHCP snooping
Switch(config)#errdisable detect cause dhcp-rate-limit
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Dynamic
UTP Fast Ethernet and Gigabit Ethernet

14. When do collisions occur?
SVI
IEEE 802.3ab
When one station transmits at the same time as another on a shared medium
400 metres half duplex and 2000 metres full duplex

15. What are the operational modes of a Layer 2 switched interface?
Switch(config-if)#switchport mode access
Configure the appropriate values manually on both ends of the link
Down - static access - trunk or tunnel
Static access or trunk

16. Selects a switch port interface and enters interface configuration mode
1000BASE-T full duplex followed by 1000BASE-T half duplex
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
Switch(config)#interface {type}{module}/{number}

17. What CEF optimisation replicates the entire FIB table among switch line cards?
Distributed CEF (dCEF)
They are dropped (ARP throttling)
Switch#show ip cef {interface} [detail]
Switch(config)#errdisable detect cause rootguard

18. What is WAN PHY used for?
Switch(config)#errdisable detect cause rootguard
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)#errdisable detect cause bpduguard
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks

19. Adds a static entry to the MAC address table
SVI or native routed interface
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
Source MAC address; Port of arrival; VLAN; Time stamp
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing

20. What is 100BASE-TX?
Switch(config)#errdisable detect cause vmps
The CEF epoch number
Switch(config)#interface {type}{module}/{number}
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP

21. Creates a switched virtual interface (SVI) and enters interface configuration mode
Switch(config)#interface vlan {vlan-id}
Static access
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
The adjacency table

22. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
The Layer 3 forwarding engine
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
The Punt adjacency

23. Enables error-disable for errors with dynamic ARP inspection
Wide-Wavelength Division Multiplexing
LAN PHY and WAN PHY
Switch(config)#errdisable detect cause arp-inspection
Switch#show interfaces {interface}

24. What information is stored in TCAM?
Switch(config-if)#shutdown
From 30 seconds to 86 -400 seconds (24 hours)
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Security and QoS ACLs

25. What is TCAM overflow?
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Switch#show adjacency [{interface}] [summary | detail]
The adjacency table
Full duplex

26. Creates an interface-range macro
Creating the VLAN
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Numeric values that represent what action to take after the TCAM lookup occurs
100 metres

27. What is the default timer for automatic re-enabling of error-disabled ports?
300 seconds
Switched virtual interface (SVI)
A name assigned to a ranges of interfaces
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)

28. What is the maximum cabling distance for 10GBASE-LR/LW?
10 km
Switch(config-if)#switchport access vlan {vlan}
With a mask value in addition to binary values to decide which keys in a table are relevant
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}

29. Displays a list of all interfaces in an error-disabled state
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
1 -2 on one end with 3 -6 on the other end
Switch(config-if)#switchport access vlan {vlan}
Switch#show interfaces status err-disabled

30. What is the maximum cabling distance for Ethernet - Fast Ethernet and Gigabit Ethernet over UTP cabling?
Interconnecting switches in a campus network
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
100 metres
FIB with adjacency table

31. What is 1000BASE-CX?
The CEF entry version number
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
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

32. Adds a description to an interface configuration
Switch(config)#errdisable detect cause arp-inspection
Switch(config-if)#description {string}
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)

33. What is the default duplex mode of a 10 Mbps Ethernet 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
Half duplex
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
On

34. What are runts?
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
Switch#show errdisable recovery
Packets that have been truncated before they were fully received
XENPAK - X2 - or SFP+

35. What is the operational mode of a switch port that is a member of one VLAN?
Switch(config)#errdisable detect cause rootguard
Static access
A station must wait its turn to transmit; it can't transmit and receive at the same time
SC or MT-RJ

36. Displays the CAM table size with number of MAC addresses
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
When one station transmits at the same time as another on a shared medium
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]

37. Enables error-disable when an interface has been looped back
Switch(config)#errdisable detect cause loopback
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Packets that have been truncated before they were fully received

38. What are the 100BASE-FX connectors used in Cisco Catalyst switches?
The Null adjacency
A switch port that has been shut down automatically due to a serious error condition
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
SC or MT-RJ

39. What is the maximum cabling distance for 10GBASE-ER/EW?
40 km
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Feature Manager (FM) and Switching Database Manager (SDM)

40. What is the administrative mode of a switch port that uses DTP to negotiate its operational mode?
Dynamic
Switch(config)#errdisable detect cause dhcp-rate-limit
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Half duplex

41. What is LOU?
Switch(config)#errdisable detect cause link-flap
Logical Operation Unit
Switch#show errdisable detect
Switch#show cef drop

42. What changes are made to packets by the CEF packet rewrite engine just before forwarding?
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
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
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
Tunnel

43. What information is recorded in CAM as frames arrive on a switch port?
Source MAC address; Port of arrival; VLAN; Time stamp
Switch(config)#errdisable recovery cause {all | {cause-name}}
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#show cef not-cef-switched

44. What is ANSI?
Slow response times - low throughput - runts and other input errors on the switch ports
Route caching and topology based
American National Standards Institute
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling

45. What CEF optimisation technique cache FIB entries in switch line cards?
Accelerated CEF (aCEF)
Electromagnetic Interference
Switch(config)#errdisable detect cause rootguard
Switch#show errdisable detect

46. What is the TCAM Value and Mask for an Ethernet access list?
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Forwarding Information Base
Source MAC (/48); Destination MAC (/48); Ethertype (/16)

47. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Switch#show ip cef {interface} [detail]
25 metres
Switch(config)#errdisable detect cause storm-control
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)

48. What is 1000BASE-LX/LH?
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
A switch port that has been shut down automatically due to a serious error condition
Trunk or dynamic
When one station transmits at the same time as another on a shared medium

49. Enables error-disable for the presence of invalid GBIC or SFP modules
Cabling specifications for Gigabit Ethernet
Switch(config)#errdisable detect cause gbic-invalid
On
SVI

50. Removes entries from the CAM table
IEEE 802.3u
Process the first packet in a traffic flow to determine the destination
1 -2 on one end with 3 -6 on the other end
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]