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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 the contents of the CAM table
Trunk or dynamic
Switch(config-if)#shutdown
Switch(config-if)#speed {10 | 100 | 1000 | auto}
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]

2. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)
The Punt adjacency
300 seconds
400 metres half duplex and 2000 metres full duplex

3. What is the DTP negotiation mode of a switch port configured as dynamic?
Route caching and topology based
Tunnel
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
On

4. What are the basic operations that a frame undergoes as it passes through a Layer 2 switch?
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
Security and QoS ACLs
Switch#show adjacency [{interface}] [summary | detail]
Numeric values that represent what action to take after the TCAM lookup occurs

5. Displays a list of all interfaces in an error-disabled state
Switch#show interfaces status err-disabled
Switch#show adjacency [{interface}] [summary | detail]
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
The switch port falls back to default setting of half duplex

6. What denotes the number of times the CEF table has been flushed and regenerated as a whole?
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
On
The CEF epoch number
Numeric values that represent what action to take after the TCAM lookup occurs

7. What are the letters used with 10GBASE-X two-letter suffixes to specify the PHY type?
The switch port falls back to default setting of half duplex
R = LAN PHY; W = WAN PHY
Carrier Sense Multiple Access Collision Detection
Distributed CEF (dCEF)

8. What technology was merged into the IEEE 802.3 Ethernet standard to create Gigabit Ethernet?
10 km
Switch(config)#errdisable detect cause udld
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
ANSI X3T11 FibreChannel

9. What is 1000BASE-LX/LH?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Switch(config-if)#switchport access vlan {vlan}
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Switch#show cef not-cef-switched

10. What is the standard for Fast Ethernet (100 Mbps)?
With a mask value in addition to binary values to decide which keys in a table are relevant
Multilayer Switching
400 metres half duplex and 2000 metres full duplex
IEEE 802.3u

11. What is the maximum cabling distance for 10GBASE-LR/LW?
The switch port falls back to default setting of half duplex
10 km
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
Trunk or dynamic

12. What type of packets can not be forwarded by CEF but are instead sent to the switch CPU for process switching in software?
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
Store-and-forward
Static access - trunk - tunnel or dynamic
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

13. What is 1000BASE-T?
Switched virtual interface (SVI)
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
The Null adjacency
Cabling specifications for 10 Gigabit Ethernet

14. What is the content of TCAM Result entries?
Switch(config)#errdisable detect cause dhcp-rate-limit
10GbE operates only at full duplex
Numeric values that represent what action to take after the TCAM lookup occurs
They are dropped (ARP throttling)

15. Displays the CAM table size with number of MAC addresses
A station must wait its turn to transmit; it can't transmit and receive at the same time
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
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#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]

16. What is unknown unicast flooding?
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
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
XENPAK - X2 - or SFP+

17. What CEF optimisation replicates the entire FIB table among switch line cards?
Distributed CEF (dCEF)
Switch(config)#errdisable detect cause gbic-invalid
Partition and tune the TCAM on some Catalyst switches into areas for different functions
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)

18. Where is source and destination addresses and other relevant protocol information for access lists stored in the TCAM table?
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
In TCAM Value entries
A name assigned to a ranges of interfaces
Switch(config)#errdisable detect cause udld

19. What two IOS software components are involved in TCAM operation?
Switch(config)#errdisable detect cause bpduguard
Feature Manager (FM) and Switching Database Manager (SDM)
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
Routing table and ARP table

20. What is the administrative mode of a switch port that is a member of one VLAN?
Static access or dynamic
Value - Mask - and Result (VMR)
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
Static access or trunk

21. What function is performed by the Feature Manager (FM)?
SVI
Compiling Access Control Entries (ACE) into the TCAM table
Static access or trunk
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

22. What is the operational mode of a switch port that carries transparent Layer 2 VPNs?
Switch(config)#errdisable detect cause rootguard
Switch(config-if)#switchport mode access
10 km
Tunnel

23. What are the common cabling specifications for Fast Ethernet?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Switch(config-if)#duplex {auto | full | half}
Switch(config)#errdisable detect cause unicast-flood

24. What is 10BASE-T?
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
When one station transmits at the same time as another on a shared medium
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
CEF glean

25. What are the operational modes of a Layer 2 switched interface?
Accelerated CEF (aCEF)
Down - static access - trunk or tunnel
S = Short; L = Long; E = Extra-long
Store-and-forward

26. What is the maximum cabling distance for 1000BASE-CX?
Switch#show errdisable recovery
Enable error-disable for all possible causes
They are dropped (ARP throttling)
25 metres

27. What CEF optimisation technique cache FIB entries in switch line cards?
In TCAM Value entries
300 seconds
Accelerated CEF (aCEF)
Switch#show errdisable detect

28. Creates an interface-range macro
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Trunk or dynamic
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#no ip cef

29. What is the default age-out time for stale entries in the CAM table?
From 30 seconds to 86 -400 seconds (24 hours)
300 seconds
Interconnecting switches in a campus network
Tunnel

30. What is the administrative mode of a switch port that carries transparent Layer 2 VPNs?
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Switch(config)#interface {type}{module}/{number}
Tunnel
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)

31. What is ANSI?
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
The switch port falls back to default setting of half duplex
American National Standards Institute
Switch#show interfaces {interface} switchport

32. What are the 10GBASE-X PMD transceiver form factors used in Cisco Catalyst switches?
XENPAK - X2 - or SFP+
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)#interface range macro {name}
Collision domain

33. What is the name of the switching technology where good frames are received - stored for inspection and then forwarded?
Switch(config)#errdisable detect cause bpduguard
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
The Null adjacency
Store-and-forward

34. How are ports that are in error-disable state re-enabled by default?
Manually by administratively disabling and re-enabling the port
Switch#show cef not-cef-switched
IEEE 802.3ab
Full duplex only

35. What is the default duplex mode of a 10 Mbps Ethernet interface?
Switch#show interfaces status
Switch(config)#interface range macro {name}
Switch#show ip cef
Half duplex

36. What is the TCAM Value and Mask for an Ethernet access list?
Ternary Content-Addressable Memory
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
Process the first packet in a traffic flow to determine the destination
Switch(config)#no ip cef

37. Displays administrative and operational status for a specified interface
Creating the VLAN
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Switch#show interfaces {interface}
R = LAN PHY; W = WAN PHY

38. What is full duplex operation?
IEEE 802.3
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

39. What is TCAM overflow?
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
The Punt adjacency
Switch(config)#errdisable detect cause {all | {cause-name}}
10 Gigabit Ethernet over copper CX4 with Infiniband connectors

40. What connectors can be used with GBIC modules?
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
IEEE 802.3
Switched virtual interface (SVI)
SC fibre optic or RJ-45 UTP

41. Displays CEF Drop statistics with number of packets and reason for each line card
Wide-Wavelength Division Multiplexing
Switch#show cef drop
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Mask bits set to 1 for Value bits of interest and 0 for Value bits that don't matter

42. What are the names of CEF optimisation techniques using specialised forwarding hardware?
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
A switch port that has been shut down automatically due to a serious error condition
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)

43. How is the TCAM organised?
Switch#show interfaces status err-disabled
By Mask/Value - where each unique mask has eight value patterns associated with it
Switch(config)#interface range macro {name}
Switch(config-if)#duplex {auto | full | half}

44. What tables are maintained by the CEF Layer 3 engine?
Full duplex only
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Slow response times - low throughput - runts and other input errors on the switch ports
Routing table and ARP table

45. What is a SVI?
Switched virtual interface (SVI)
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF
Switch(config)#interface range macro {name}
The switch port falls back to default setting of half duplex

46. Enables error-disable when trunking encapsulation is flapping from one type to another
Switch#show errdisable recovery
IEEE 802.3z
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
Switch(config)#errdisable detect cause dtp-flap

47. Sets the duplex mode of an Ethernet or Fast Ethernet interface
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Content-Addressable Memory
Switch(config-if)#duplex {auto | full | half}
Switch#show running-config interface {interface}

48. What function is performed by the Switching Database Manager (SDM)?
A switch port that has been shut down automatically due to a serious error condition
Switch#show interfaces {interface} switchport
The Discard adjacency
Partition and tune the TCAM on some Catalyst switches into areas for different functions

49. What is the administrative mode of a switch port that uses DTP to negotiate its operational mode?
Distributed CEF (dCEF)
Dynamic
Configure the appropriate values manually on both ends of the link
Static access or trunk

50. What is the name of a Layer 3 logical interface on a switch that represents an entire VLAN?
LC - MT-RJ or RJ-45
SVI
IEEE 802.3
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)