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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. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Switch(config)#errdisable detect cause l2ptguard
Half duplex
Electromagnetic Interference
Switch(config)#errdisable detect cause channel-misconfig

2. What tables are maintained by the CEF Layer 3 engine?
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
CEF glean
Switch(config)#errdisable recovery interval {seconds}
Routing table and ARP table

3. What are the default error-disable detection causes?
The switch port falls back to default setting of half duplex
S = Short; L = Long; E = Extra-long
Security and QoS ACLs
Enable error-disable for all possible causes

4. Displays switch port information for a specified interface
Switch#show interfaces {interface} switchport
A three-fold combination of 0 - 1 and X (don't care)
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
LOU registers

5. Displays administrative and operational status for a specified interface
Switch#show interfaces {interface}
Logical Operation Unit
Full duplex
Switch(config)#errdisable detect cause udld

6. What is 1000BASE-SX?
10 km
Switch#show running-config interface {interface}
Packets that have been truncated before they were fully received
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)

7. What are the reasons for packets being dropped by CEF?
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
S = Short; L = Long; E = Extra-long
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Switch#show cef drop

8. How are ports that are in error-disable state re-enabled by default?
Manually by administratively disabling and re-enabling the port
CEF punt
American National Standards Institute
Switch#show interfaces status err-disabled

9. What is 10GBASE-X?
Electromagnetic Interference
Switch(config)#errdisable detect cause unicast-flood
Wide-Wavelength Division Multiplexing
Cabling specifications for 10 Gigabit Ethernet

10. What is a ternary combination?

11. Displays a list with status of all interfaces
R = LAN PHY; W = WAN PHY
Switch(config)#mac address-table aging-time {seconds}
Packets that have been truncated before they were fully received
Switch#show interfaces status

12. What is the maximum cabling distance for 10GBASE-ER/EW?
Switch(config)#errdisable recovery cause {all | {cause-name}}
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
Institute of Electrical and Electronics Engineers
40 km

13. What RJ-45 pins must be swapped in a Category 5 UTP crossover cable for Gigabit Ethernet?
They are dropped (ARP throttling)
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)
Switch(config)#errdisable detect cause loopback
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

14. What is 1000BASE-T?
300 seconds
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
XENPAK - X2 - or SFP+

15. Configures the maximum ageing time for entries in the MAC address table
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
Switch(config)#errdisable detect cause vmps
Switch(config)#mac address-table aging-time {seconds}
Wide-Wavelength Division Multiplexing

16. What is the default age-out time for stale entries in the CAM table?
S = Short; L = Long; E = Extra-long
Switch(config)#errdisable detect cause ilpower
300 seconds
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link

17. What are the Fast Ethernet autonegotiation selection priorities?
Cisco Express Forwarding
Numeric values that represent what action to take after the TCAM lookup occurs
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
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

18. Disables CEF operation on an interface
Switch(config-if)#no ip route-cache cef
Switch(config)#mac address-table aging-time {seconds}
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
On

19. What is ANSI?
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
American National Standards Institute
R = LAN PHY; W = WAN PHY

20. What is the TCAM Value and Mask for an extended IP access list using TCP/UDP?
Tunnel
Switch(config)#errdisable detect cause loopback
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
Switch(config)#errdisable detect cause udld

21. What is LOU?
Logical Operation Unit
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
FIB with adjacency table
Switch(config)#errdisable detect cause arp-inspection

22. What are the basic operations that a frame undergoes as it passes through a Layer 2 switch?
Source MAC address; Port of arrival; VLAN; Time stamp
Institute of Electrical and Electronics Engineers
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

23. What is 1000BASE-CX?
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
SVI
Value - Mask - and Result (VMR)
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling

24. When should CEF be disabled?
Ternary Content-Addressable Memory
IEEE 802.3u
Switch(config)#errdisable detect cause link-flap
Only temporarily for debugging purposes

25. What is the TCAM Value and Mask for an IPX access list?
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Route caching and topology based
Only temporarily for debugging purposes

26. What two IOS software components are involved in TCAM operation?
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
Feature Manager (FM) and Switching Database Manager (SDM)
The switch port falls back to default setting of half duplex
Switch(config)#errdisable detect cause gbic-invalid

27. What CEF adjacency is used to discard packets because of access list or other policy action?
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
The Discard adjacency
CEF punt
10 km

28. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Switch#show ip cef {interface} [detail]

29. What is the administrative mode of a switch port that carries traffic for multiple VLANs?
Tunnel
Switch(config)#interface {type}{module}/{number}
A switch port that has been shut down automatically due to a serious error condition
Trunk or dynamic

30. Enables error-disable for errors with dynamic ARP inspection
Switch(config)#errdisable detect cause arp-inspection
S = Short; L = Long; E = Extra-long
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
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance

31. What is the content of TCAM Result entries?
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Cisco Express Forwarding
Switch(config)#errdisable detect cause unicast-flood
Numeric values that represent what action to take after the TCAM lookup occurs

32. What is the TCAM Value and Mask for an IGMP access list?
The Punt adjacency
ANSI X3T11 FibreChannel
LAN PHY and WAN PHY
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)

33. What is error-disable state?
A switch port that has been shut down automatically due to a serious error condition
Route caching and topology based
Switch(config)#errdisable detect cause vmps
CEF punt

34. Displays CEF adjacency table information
Value - Mask - and Result (VMR)
Switch#show adjacency [{interface}] [summary | detail]
Trunk
Static access

35. Displays a list of all interfaces in an error-disabled state
Switch#show interfaces status err-disabled
Switch#show interfaces status
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
The Null adjacency

36. Adds a description to an interface configuration
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Switch(config-if)#description {string}
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Source MAC address; Port of arrival; VLAN; Time stamp

37. How are the TCAM Mask/Value pairs evaluated?
Full duplex only
In TCAM Value entries
In parallel revealing the best (longest) match in a single table lookup
Switch(config-if)#description {string}

38. What is the TCAM Value and Mask for an ICMP access list?
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#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show mac address-table static [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)

39. Specifies the timer for automatic re-enabling of error-disabled ports
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
IEEE 802.3ab
Switch(config)#errdisable recovery interval {seconds}
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding

40. What are the administrative modes of Layer 2 switched interfaces?
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Static access - trunk - tunnel or dynamic
Partition and tune the TCAM on some Catalyst switches into areas for different functions

41. What are the duplex modes of a GigaStack GBIC?
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)
Tunnel
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]

42. What denotes the number of times the CEF table has been flushed and regenerated as a whole?
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
The CEF epoch number
10 km
Off

43. Enables error-disable when an STP BPDU is received from a root bridge on an unexpected port
Switch(config)#errdisable detect cause l2ptguard
Switch(config)#errdisable detect cause rootguard
The CEF epoch 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

44. What portion of the FIB contains the Layer 3 next-hop addresses for each entry together with the corresponding Layer 2 information?
The adjacency table
Switch(config-if)#shutdown
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Partition and tune the TCAM on some Catalyst switches into areas for different functions

45. 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
A three-fold combination of 0 - 1 and X (don't care)
Switch(config-if)#no ip route-cache cef
Multilayer Switching

46. Enables error-disable for misconfiguration of EtherChannel bundles
100 metres
Creating the VLAN
With a mask value in addition to binary values to decide which keys in a table are relevant
Switch(config)#errdisable detect cause channel-misconfig

47. What is the role of a Switch Engine (SE) in first generation MLS?
Switch(config)#interface vlan {vlan-id}
10GbE operates only at full duplex
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
Manually by administratively disabling and re-enabling the port

48. What is MLS?
Compiling Access Control Entries (ACE) into the TCAM table
Multilayer Switching
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Switch#show ip cef

49. What is the role of a Route Processor (RP) in first generation MLS?
Process the first packet in a traffic flow to determine the destination
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Switch(config)#errdisable detect cause channel-misconfig
Switch(config-if)#shutdown

50. Displays the CAM table size with number of MAC addresses
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
From 30 seconds to 86 -400 seconds (24 hours)
By Mask/Value - where each unique mask has eight value patterns associated with it
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF