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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 packets are immediately sent to the CEF Layer 3 engine for further processing?

2. Enables automatic re-enabling of error-disabled ports
Static access or trunk
Switch(config)#errdisable recovery cause {all | {cause-name}}
Value - Mask - and Result (VMR)
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF

3. Displays error-disabled recovery timer information
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
Trunk or dynamic
Switch#show errdisable recovery
Switch(config)#errdisable detect cause storm-control

4. What is the standard for 10 Gigabit Ethernet (10GbE)?
IEEE 802.3u
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
IEEE 802.3ae
Switch(config-if)#description {string}

5. Where is source and destination addresses and other relevant protocol information for access lists stored in the TCAM table?
When one station transmits at the same time as another on a shared medium
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
In TCAM Value entries
Trunk

6. What is FIB?
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
LC - MT-RJ or RJ-45
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)
Forwarding Information Base

7. Enables error-disable for Bridge Protocol Data Units (BPDU) received on ports configured for STP PortFast
Switch(config)#errdisable detect cause bpduguard
FIB with adjacency table
Switch#show adjacency [{interface}] [summary | detail]
Switch(config)#errdisable detect cause psecure-violation

8. Adds a description to an interface configuration
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Switch(config-if)#no ip route-cache cef
The Drop adjacency
Switch(config-if)#description {string}

9. Displays error-disabled detection status
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Switch#show errdisable detect
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
1 -2 on one end with 3 -6 on the other end

10. What is Cisco's old recommendation regarding switch port speed and duplex mode?
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Configure the appropriate values manually on both ends of the link
SC or MT-RJ
10GbE operates only at full duplex

11. Enables error-disable for errors when assigning a port to a dynamic VLAN through a VMPS
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Switch(config)#errdisable detect cause vmps
Routing table and ARP table

12. What type of packets can not be forwarded by CEF but are instead sent to the switch CPU for process switching in software?
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
1 -2 on one end with 3 -6 on the other end
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
The Layer 3 forwarding engine

13. What is 10GBASE-ER/EW?
Switch(config)#errdisable recovery cause {all | {cause-name}}
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)

14. What is the operational mode of a switch port that carries transparent Layer 2 VPNs?
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Switch(config-if)#switchport mode access
Tunnel
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)

15. What are runts?
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-if)#switchport mode access
Packets that have been truncated before they were fully received
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)

16. What is the TCAM Value and Mask for an Ethernet access list?
IEEE 802.3
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
Switch(config)#errdisable detect cause unicast-flood

17. What is the TCAM Value and Mask for an extended IP access list using TCP/UDP?
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
300 seconds
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
LC - MT-RJ or RJ-45

18. What portion of the FIB contains the Layer 3 next-hop addresses for each entry together with the corresponding Layer 2 information?
CEF glean
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Ternary Content-Addressable Memory
The adjacency table

19. What is 1000BASE-T?
Switch#show errdisable recovery
American National Standards Institute
IEEE 802.3ae
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP

20. What is 10GBASE-LX4/LW4?
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Source MAC (/48); Destination MAC (/48); Ethertype (/16)

21. Selects a switch port interface and enters interface configuration mode
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
Trunk or dynamic
Switch(config)#interface {type}{module}/{number}
400 metres half duplex and 2000 metres full duplex

22. What is 100BASE-T2?
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Logical Operation Unit
LOU registers
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling

23. What denotes the number of times the CEF table has been flushed and regenerated as a whole?
Packets that have been truncated before they were fully received
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
The CEF epoch number

24. What is the operational mode of a switch port that is a member of one VLAN?
In TCAM Value entries
Static access - trunk - tunnel or dynamic
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
Static access

25. What are the operational modes of a Layer 2 switched interface?
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Down - static access - trunk or tunnel
1000BASE-T full duplex followed by 1000BASE-T half duplex
With a mask value in addition to binary values to decide which keys in a table are relevant

26. What is the maximum cabling distance for 1000BASE-CX?
40 km
Switch(config-if)#switchport mode access
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
25 metres

27. Resets the configuration of a switch port to its default values
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
The Layer 3 engine
Switch(config)#default interface {interface}

28. What happens when autonegotiating of link duplex mode fails on a Fast Ethernet link?
Switch(config)#interface vlan {vlan-id}
Routing table and ARP table
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
The switch port falls back to default setting of half duplex

29. Enables error-disable for conditions that trigger port security configured on a port
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
Full duplex
Switch(config)#errdisable detect cause psecure-violation
Distributed CEF (dCEF)

30. Displays CEF Punt statistics with number of packets and reason for each line card
On
Switch(config)#mac address-table aging-time {seconds}
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch#show cef not-cef-switched

31. What happens to subsequent packets destined for FIB entries in CEF glean state?
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
70 km for 9 micron SMF; 100 km for 8 micron SMF
They are dropped (ARP throttling)
IEEE 802.3z

32. How do Layer 2 switches provide isolation between hosts?
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
UTP Fast Ethernet and Gigabit Ethernet
15 metres
Interconnecting switches in a campus network

33. What is the maximum cabling distance for 10GBASE-LX4/LW4?
Switch(config-if)#no switchport
Switch(config)#errdisable detect cause {all | {cause-name}}
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP

34. What is the maximum cabling distance for Fast Ethernet over 62.5/125 micron multimode fibre?
400 metres half duplex and 2000 metres full duplex
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
70 km for 9 micron SMF; 100 km for 8 micron SMF
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing

35. What is 1000BASE-SX?
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Electromagnetic Interference

36. What is the DTP negotiation mode of a switch port configured as static access?
Source MAC address; Port of arrival; VLAN; Time stamp
Off
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Full duplex only

37. What is ANSI?
American National Standards Institute
Enable error-disable for all possible causes
Interconnecting switches in a campus network
IEEE 802.3ae

38. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Static access or trunk
Switch(config)#errdisable detect cause l2ptguard
The Null adjacency
Value - Mask - and Result (VMR)

39. What is Fast EtherChannel (FEC)?
FIB with adjacency table
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)

40. What is the name of the CEF engine that forwards packets in hardware?
Static access or trunk
The Layer 3 forwarding engine
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
Switch(config)#errdisable detect cause {all | {cause-name}}

41. What are the symptoms of a duplex setting mismatch between two ends of a link?
Slow response times - low throughput - runts and other input errors on the switch ports
Switch(config)#errdisable detect cause pagp-flap
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Mask bits set to 1 for Value bits of interest and 0 for Value bits that don't matter

42. What is the maximum cabling distance for 1000BASE-LX/LH?
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch(config-if)#switchport access vlan {vlan}
SC fibre optic or RJ-45 UTP
Switch(config)#mac address-table aging-time {seconds}

43. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Switch(config)#errdisable detect cause {all | {cause-name}}
Collision domain
Value - Mask - and Result (VMR)
Switch#show ip cef {interface} [detail]

44. What are the common cabling specifications for Fast Ethernet?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Switch(config)#errdisable detect cause rootguard
Trunk or dynamic
Slow response times - low throughput - runts and other input errors on the switch ports

45. What RJ-45 pins have been swapped in a Category 5 UTP crossover cable for Fast Ethernet?
SC or MT-RJ
R = LAN PHY; W = WAN PHY
1 -2 on one end with 3 -6 on the other end
The CEF epoch number

46. What is TCAM overflow?
Switch(config)#errdisable detect cause l2ptguard
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP

47. What is 10GBASE-SR/SW?
Enable error-disable for all possible causes
Content-Addressable Memory
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)

48. Enables error-disable for when the port link state is flapping between the up and down states
Switch(config)#errdisable detect cause link-flap
FIB with adjacency table
Switch#show interfaces status
Switch(config)#errdisable detect cause rootguard

49. What connectors can be used with SFP modules?
The Discard adjacency
LC - MT-RJ or RJ-45
Full duplex
Security and QoS ACLs

50. What are the administrative modes of Layer 2 switched interfaces?
Static access - trunk - tunnel or dynamic
Switch#show errdisable recovery
10 km
Switch(config)#errdisable recovery interval {seconds}