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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 is Fast EtherChannel (FEC)?
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
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Switch(config)#errdisable detect cause arp-inspection
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]

2. What are the common PMD types for 10 Gigabit Ethernet?
They are dropped (ARP throttling)
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
Switch#show interfaces status err-disabled
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP

3. Enables error-disable for when the port link state is flapping between the up and down states
Switch#show interfaces status err-disabled
Switch(config-if)#switchport access vlan {vlan}
Switch(config)#errdisable detect cause link-flap
LAN PHY and WAN PHY

4. What is the standard for 1000BASE-T?
Switch(config)#mac address-table aging-time {seconds}
IEEE 802.3ab
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Switch(config-if)#speed {10 | 100 | 1000 | auto}

5. What is the DTP negotiation mode of a switch port configured as trunk?
Switch(config-if)#switchport mode access
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
On

6. What are the default error-disable detection causes?
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
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#show cef drop
Enable error-disable for all possible causes

7. What is ANSI?
XENPAK - X2 - or SFP+
Tunnel
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
American National Standards Institute

8. Enables error-disable when an STP BPDU is received from a root bridge on an unexpected port
25 metres
Switch(config)#errdisable detect cause rootguard
The Punt adjacency
Switch#show ip cef

9. What is the name of the switching technology where good frames are received - stored for inspection and then forwarded?
Switch#show errdisable detect
Switch(config)#errdisable detect cause security-violation
Slow response times - low throughput - runts and other input errors on the switch ports
Store-and-forward

10. What is 1000BASE-CX?
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Static access or dynamic
On
LAN PHY and WAN PHY

11. What mechanism does the TCAM provide for Layer 4 comparisons involving gt - lt - neq or range operators?
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Trunk or dynamic
Switch(config)#errdisable detect cause dhcp-rate-limit
LOU registers

12. What is 10GBASE-LR/LW?
Value - Mask - and Result (VMR)
Switch(config)#interface range macro {name}
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
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)

13. What type of packets can not be forwarded by CEF but are instead sent to the switch CPU for process switching in software?
Switch(config)#errdisable detect cause rootguard
Switch#show errdisable detect
Partition and tune the TCAM on some Catalyst switches into areas for different functions
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

14. Displays administrative and operational status for a specified interface
Slow response times - low throughput - runts and other input errors on the switch ports
Switch(config)#errdisable detect cause bpduguard
Switch#show interfaces {interface}
10 Gigabit Ethernet over copper CX4 with Infiniband connectors

15. Sets the administrative mode of a switch port to access
Route caching and topology based
Switch(config-if)#switchport mode access
A station must wait its turn to transmit; it can't transmit and receive at the same time
Only temporarily for debugging purposes

16. What is the default duplex mode of a Gigabit Ethernet interface?
Cabling specifications for 10 Gigabit Ethernet
Full duplex
SC fibre optic or RJ-45 UTP
Manually by administratively disabling and re-enabling the port

17. What is the name of the CEF engine that forwards packets in hardware?
Switch#show errdisable recovery
The Layer 3 forwarding engine
100 metres
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance

18. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Switch(config)#errdisable detect cause l2ptguard
R = LAN PHY; W = WAN PHY
The Layer 3 forwarding engine
Switch(config-if)#shutdown

19. Configures the maximum ageing time for entries in the MAC address table
American National Standards Institute
SVI
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Switch(config)#mac address-table aging-time {seconds}

20. Enables error-disable for misconfiguration of EtherChannel bundles
UTP Fast Ethernet and Gigabit Ethernet
XENPAK - X2 - or SFP+
Route caching and topology based
Switch(config)#errdisable detect cause channel-misconfig

21. What is FIB?
Full duplex
Forwarding Information Base
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
Switch(config)#errdisable detect cause pagp-flap

22. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Switch#show ip cef {interface} [detail]
Switch(config)#errdisable detect cause udld
American National Standards Institute
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)

23. What is full duplex operation?
Switch(config)#interface {type}{module}/{number}
S = Short; L = Long; E = Extra-long
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
A three-fold combination of 0 - 1 and X (don't care)

24. What is CAM?
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Content-Addressable Memory
Routing table and ARP table
Source MAC (/48); Destination MAC (/48); Ethertype (/16)

25. What are the Gigabit Ethernet autonegotiation selection priorities?
1000BASE-T full duplex followed by 1000BASE-T half duplex
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
A switch port that has been shut down automatically due to a serious error condition
Switch(config)#errdisable recovery interval {seconds}

26. What is the maximum cabling distance for 10GBASE-CX4?
Institute of Electrical and Electronics Engineers
15 metres
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch(config-if)#shutdown

27. Enables error-disable for errors with offering inline power
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
Switch(config)#errdisable detect cause udld
Switch(config)#errdisable detect cause ilpower
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

28. What are the reasons for packets being dropped by CEF?
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
1 -2 on one end with 3 -6 on the other end

29. What is the prerequesite for creating a working SVI?
Switch#show running-config interface {interface}
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Creating the VLAN
Switch(config)#errdisable detect cause channel-misconfig

30. What is LOU?
Full duplex only
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Logical Operation Unit
Enable error-disable for all possible causes

31. What CEF optimisation technique cache FIB entries in switch line cards?
The CEF entry version number
Tunnel
Accelerated CEF (aCEF)
Interconnecting switches in a campus network

32. Enables error-disable for Bridge Protocol Data Units (BPDU) received on ports configured for STP PortFast
From 30 seconds to 86 -400 seconds (24 hours)
Logical Operation Unit
Switch(config)#errdisable detect cause bpduguard
Trunk or dynamic

33. What tables are maintained by the CEF Layer 3 engine?
Routing table and ARP table
300 seconds
Switch#show interfaces status
70 km for 9 micron SMF; 100 km for 8 micron SMF

34. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
On
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
10 km

35. When should CEF be disabled?
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
Switch(config)#default interface {interface}
By Mask/Value - where each unique mask has eight value patterns associated with it
Only temporarily for debugging purposes

36. When can a switch start to learn source MAC addresses on incoming ports?
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
Switch(config-if)#no ip route-cache cef
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
Off

37. What is the timer range for automatic re-enabling of error-disabled ports?
From 30 seconds to 86 -400 seconds (24 hours)
Wide-Wavelength Division Multiplexing
Cisco Express Forwarding
Accelerated CEF (aCEF) and Distributed CEF (dCEF)

38. What is an interface-range macro?
A name assigned to a ranges of interfaces
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
10 km
UTP Fast Ethernet and Gigabit Ethernet

39. What are the names of CEF optimisation techniques using specialised forwarding hardware?
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
UTP Fast Ethernet and Gigabit Ethernet

40. What is the maximum cabling distance for 1000BASE-LX/LH?
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)
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
15 metres
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF

41. Enables error-disable for errors when assigning a port to a dynamic VLAN through a VMPS
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Slow response times - low throughput - runts and other input errors on the switch ports
Switch#show errdisable recovery
Switch(config)#errdisable detect cause vmps

42. What is 1000BASE-LX/LH?
IEEE 802.3ab
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Half duplex

43. What are the reasons for packets being punted by CEF?
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)
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-if)#no switchport
SVI or native routed interface

44. Enables error-disable for the presence of invalid GBIC or SFP modules
300 seconds
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
Switch(config)#errdisable detect cause gbic-invalid
Switch#show interfaces {interface}

45. What connectors can be used with SFP modules?
LC - MT-RJ or RJ-45
A name assigned to a ranges of interfaces
Collision domain
Tunnel

46. What two IOS software components are involved in TCAM operation?
Switch(config)#errdisable detect cause gbic-invalid
Institute of Electrical and Electronics Engineers
Feature Manager (FM) and Switching Database Manager (SDM)
Switch#show errdisable detect

47. What is 10BASE-T?
By Mask/Value - where each unique mask has eight value patterns associated with it
Down - static access - trunk or tunnel
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling

48. What RJ-45 pins have been swapped in a Category 5 UTP crossover cable for Fast Ethernet?
Dynamic
1 -2 on one end with 3 -6 on the other end
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Switch(config)#errdisable detect cause storm-control

49. What is 1000BASE-SX?
On
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
Switch(config)#errdisable detect cause dtp-flap

50. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
XENPAK - X2 - or SFP+
IEEE 802.3ab
The Punt adjacency
American National Standards Institute