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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. Resets the configuration of a switch port to its default values
Manually by administratively disabling and re-enabling the port
Switch(config)#errdisable recovery interval {seconds}
American National Standards Institute
Switch(config)#default interface {interface}

2. Displays the CAM table size with number of MAC addresses
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show cef not-cef-switched
IEEE 802.3u

3. Adds a static entry to the MAC address table
10 km
The table of learned MAC addresses - ports - and VLAN information
Electromagnetic Interference
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}

4. Displays CEF Drop statistics with number of packets and reason for each line card
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
Feature Manager (FM) and Switching Database Manager (SDM)
Switch#show ip cef
Switch#show cef drop

5. What is full duplex operation?
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Source MAC address; Port of arrival; VLAN; Time stamp
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

6. What are GigaStack GBICs used for?
Distributed CEF (dCEF)
Switch#show interfaces {interface} switchport
The Drop adjacency
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance

7. Enables error-disable for errors related to 802.1x security
XENPAK - X2 - or SFP+
Switch(config)#errdisable detect cause security-violation
Switch(config)#errdisable detect cause storm-control
The Drop adjacency

8. What is CAM?
Slow response times - low throughput - runts and other input errors on the switch ports
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Content-Addressable Memory
Enable error-disable for all possible causes

9. What happens to subsequent packets destined for FIB entries in CEF glean state?
They are dropped (ARP throttling)
Switch(config)#errdisable detect cause psecure-violation
IEEE 802.3ab
Partition and tune the TCAM on some Catalyst switches into areas for different functions

10. What is TCAM overflow?
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
The adjacency table
Switch#show cef drop

11. What are the Fast Ethernet autonegotiation selection priorities?
Logical Operation Unit
Electromagnetic Interference
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)
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

12. What is the state of packets that are sent to the CEF Layer 3 engine because of missing Layer 2 next-hop addresses?
CEF glean
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
IEEE 802.3
Creating the VLAN

13. Enables error-disable when an interface has been looped back
Store-and-forward
Native routed interface
Switch(config)#errdisable detect cause loopback
The table of learned MAC addresses - ports - and VLAN information

14. Enables error-disable when an STP BPDU is received from a root bridge on an unexpected port
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
Switch#show interfaces status
Switch(config)#errdisable detect cause rootguard
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries

15. What is the content of TCAM Result entries?
Collision domain
Numeric values that represent what action to take after the TCAM lookup occurs
The switch port falls back to default setting of half duplex
Switch#show interfaces status

16. Displays interface configuration information
Switch#show adjacency [{interface}] [summary | detail]
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
Switch#show running-config interface {interface}

17. What two IOS software components are involved in TCAM operation?
Slow response times - low throughput - runts and other input errors on the switch ports
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
On
Feature Manager (FM) and Switching Database Manager (SDM)

18. How are MAC addresses shown in the detailed output from the CEF adjacency table?
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Switch#show ip cef {interface} [detail]
Listen to the first packet and put its resulting destination in the MLS cache; Route subsequent packets in the same flow based on the MLS cache
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)

19. What CEF adjacency is used to switch packets destined for the null interface?
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Numeric values that represent what action to take after the TCAM lookup occurs
Switch(config-if)#switchport mode access
The Null adjacency

20. What is the TCAM Value and Mask for an IPX access list?
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
IEEE 802.3ab
Switch(config)#errdisable recovery cause {all | {cause-name}}
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)

21. What is the TCAM Value and Mask for an ICMP access list?
Process the first packet in a traffic flow to determine the destination
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)
Switch#show interfaces status err-disabled

22. Displays error-disabled detection status
In TCAM Value entries
Switch#show errdisable detect
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Electromagnetic Interference

23. 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
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
Switch(config-if)#no switchport
25 metres

24. Displays a list of all interfaces in an error-disabled state
Switch#show interfaces status err-disabled
American National Standards Institute
Value - Mask - and Result (VMR)
Content-Addressable Memory

25. What are the common PMD types for 10 Gigabit Ethernet?
Accelerated CEF (aCEF)
The Layer 3 forwarding engine
IEEE 802.3
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4

26. Selects multiple switch port interfaces at the same time and enters interface configuration mode
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
Routing table and ARP table
SVI or native routed interface
Creating the VLAN

27. Displays CEF Punt statistics with number of packets and reason for each line card
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
Switch#show cef not-cef-switched
Switch(config)#interface range macro {name}
The table of learned MAC addresses - ports - and VLAN information

28. Enables error-disable for Bridge Protocol Data Units (BPDU) received on ports configured for STP PortFast
Switch(config)#errdisable detect cause bpduguard
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
S = Short; L = Long; E = Extra-long
Listen to the first packet and put its resulting destination in the MLS cache; Route subsequent packets in the same flow based on the MLS cache

29. 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
Trunk or dynamic
SVI
When one station transmits at the same time as another on a shared medium

30. Configures a switch port with a static access VLAN assignment
Switch(config)#errdisable detect cause rootguard
Switch(config-if)#switchport access vlan {vlan}
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
Switch(config)#errdisable detect cause bpduguard

31. What is 100BASE-TX?
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
A name assigned to a ranges of interfaces
Switch(config)#errdisable detect cause loopback
Trunk

32. What are the basic operations that a frame undergoes as it passes through a multilayer switch?
They are dropped (ARP throttling)
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
LAN PHY and WAN PHY
Accelerated CEF (aCEF)

33. What is the operational mode of a switch port that uses DTP negotiation?
Carrier Sense Multiple Access Collision Detection
Static access or trunk
Switch(config)#errdisable detect cause ilpower
Value - Mask - and Result (VMR)

34. 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
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
400 metres half duplex and 2000 metres full duplex
Switch(config)#errdisable detect cause dtp-flap

35. What RJ-45 pins must be swapped in a Category 5 UTP crossover cable for Gigabit Ethernet?
100 metres
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
SC fibre optic or RJ-45 UTP
Switch(config)#errdisable detect cause unicast-flood

36. Sets the duplex mode of an Ethernet or Fast Ethernet interface
Switch(config)#errdisable detect cause dhcp-rate-limit
Switch(config-if)#duplex {auto | full | half}
Switch#show cef drop
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state

37. Enables error-disable for rate-limiting of DHCP snooping
Switch(config)#errdisable detect cause dhcp-rate-limit
SVI
The Null adjacency
The table of learned MAC addresses - ports - and VLAN information

38. Enables error-disable when trunking encapsulation is flapping from one type to another
The table of learned MAC addresses - ports - and VLAN information
Switch(config)#errdisable detect cause dtp-flap
Half duplex
With a mask value in addition to binary values to decide which keys in a table are relevant

39. Configures the maximum ageing time for entries in the MAC address 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
Switch(config-if)#switchport access vlan {vlan}
ANSI X3T11 FibreChannel
Switch(config)#mac address-table aging-time {seconds}

40. What information is stored in TCAM?
Slow response times - low throughput - runts and other input errors on the switch ports
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
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
Security and QoS ACLs

41. Displays the contents of the CAM table
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(config)#errdisable detect cause arp-inspection
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show cef drop

42. Selects an interface-range macro and enters interface configuration mode
Switch(config)#no ip cef
Full duplex only
Switch(config)#interface range macro {name}
By Mask/Value - where each unique mask has eight value patterns associated with it

43. What is the standard for Fast Ethernet (100 Mbps)?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
IEEE 802.3u
Switch(config)#errdisable detect cause bpduguard

44. Sets the speed of a Fast Ethernet or Gigabit Ethernet interface
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Switch(config-if)#speed {10 | 100 | 1000 | auto}
400 metres half duplex and 2000 metres full duplex
American National Standards Institute

45. What is the DTP negotiation mode of a switch port configured as dynamic?
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)
Static access or trunk
On

46. How are the TCAM Mask/Value pairs evaluated?
Tunnel
In parallel revealing the best (longest) match in a single table lookup
Slow response times - low throughput - runts and other input errors on the switch ports
Carrier Sense Multiple Access Collision Detection

47. What is the maximum cabling distance for Fast Ethernet over 62.5/125 micron multimode fibre?
SVI
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
Switch(config)#errdisable recovery interval {seconds}
400 metres half duplex and 2000 metres full duplex

48. What combinations are TCAM entries composed of?
Value - Mask - and Result (VMR)
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)

49. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
10 km
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Interconnecting switches in a campus network
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link

50. What is the role of a Switch Engine (SE) in first generation MLS?
Down - static access - trunk or tunnel
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
The CEF entry version number
Listen to the first packet and put its resulting destination in the MLS cache; Route subsequent packets in the same flow based on the MLS cache