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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 information is recorded in CAM as frames arrive on a switch port?
Off
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
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

2. Enables error-disable for when the port link state is flapping between the up and down states
Switch(config)#errdisable detect cause link-flap
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
Cabling specifications for 10 Gigabit Ethernet

3. Enables error-disable for errors with dynamic ARP inspection
Switch(config)#errdisable detect cause arp-inspection
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF
Switch(config-if)#speed {10 | 100 | 1000 | auto}
LC - MT-RJ or RJ-45

4. What is the name of physical network segment where data packets can collide with one another when being sent?
Only temporarily for debugging purposes
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
100 metres
Collision domain

5. What combinations are TCAM entries composed of?
Distributed CEF (dCEF)
Value - Mask - and Result (VMR)
FIB with adjacency table
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)

6. What two IOS software components are involved in TCAM operation?
Switch(config)#interface {type}{module}/{number}
Feature Manager (FM) and Switching Database Manager (SDM)
Switch(config)#errdisable detect cause security-violation
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)

7. What are the common cabling specifications for Gigabit Ethernet?
American National Standards Institute
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
IEEE 802.3u
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX

8. What is the TCAM Value and Mask for an IGMP access list?
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
10 km

9. What is the name of the CEF engine that forwards packets in hardware?
The Layer 3 forwarding engine
Switch#show errdisable recovery
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
By electrical signalling so that either end of a link can determine what speed the other end is trying to use

10. What are the names of CEF optimisation techniques using specialised forwarding hardware?
FIB with adjacency table
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
They are dropped (ARP throttling)
Accelerated CEF (aCEF) and Distributed CEF (dCEF)

11. What tables are maintained by the CEF Layer 3 forwarding engine?
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Switch#show cef drop
FIB with adjacency table
Routing table and ARP table

12. What is the content of TCAM Mask entries?

13. What is 1000BASE-LX/LH?
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
The CEF entry version number
SVI or native routed interface
Switch(config-if)#switchport access vlan {vlan}

14. What is the default duplex mode of a 10 Mbps Ethernet interface?
Half duplex
Switch(config)#errdisable detect cause psecure-violation
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
Switch#show running-config interface {interface}

15. What is the DTP negotiation mode of a switch port configured as dynamic?
Switch(config-if)#no switchport
On
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
S = Short; L = Long; E = Extra-long

16. Displays the entire Forwarding Information Base (FIB)
Switch(config)#errdisable detect cause udld
Switch#show ip cef
FIB with adjacency table
Switch#show cef drop

17. Selects multiple switch port interfaces at the same time and enters interface configuration mode
Creating the VLAN
Switch(config)#errdisable detect cause dtp-flap
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
CEF glean

18. What is the TCAM Value and Mask for an Ethernet access list?
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
SVI or native routed interface
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
Switch(config)#errdisable detect cause storm-control

19. What is 10BASE-T?
Switch(config)#errdisable detect cause unicast-flood
LC - MT-RJ or RJ-45
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Switch(config-if)#switchport access vlan {vlan}

20. What is the name of a Layer 3 physical interface on a switch?
SVI or native routed interface
Native routed interface
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
The table of learned MAC addresses - ports - and VLAN information

21. What is the original standard for Ethernet (10 Mbps)?
Switch(config)#interface {type}{module}/{number}
IEEE 802.3
Down - static access - trunk or tunnel
Half duplex

22. What is the maximum cabling distance for 1000BASE-LX/LH?
Static access or trunk
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
From 30 seconds to 86 -400 seconds (24 hours)
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF

23. What is CEF?
Cisco Express Forwarding
Institute of Electrical and Electronics Engineers
ANSI X3T11 FibreChannel
American National Standards Institute

24. What is 10GBASE-LR/LW?
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
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
With MMF cables shorter than 100 metres (to prevent over-driving the far-end receiver) and with MMF cables longer than 300 metres (to lessen the effect of differential mode delay)
Creating the VLAN

25. 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
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
LOU registers
Switch#show adjacency [{interface}] [summary | detail]

26. What are the 10GBASE-X PMD transceiver form factors used in Cisco Catalyst switches?
Dynamic
XENPAK - X2 - or SFP+
The table of learned MAC addresses - ports - and VLAN information
IEEE 802.3u

27. What CEF adjacency is used to switch packets that can't be forwarded normally?
Security and QoS ACLs
The Drop adjacency
Switch(config)#errdisable detect cause unicast-flood
Static access

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

29. Displays static CAM table entries
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#default interface {interface}
Switch(config)#errdisable detect cause dhcp-rate-limit
Switch(config)#mac address-table aging-time {seconds}

30. What Ethernet ports allow for autonegotiation?
UTP Fast Ethernet and Gigabit Ethernet
Down - static access - trunk or tunnel
Tunnel
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

31. What information is stored in TCAM?
Enable error-disable for all possible causes
Switch(config)#interface range macro {name}
Security and QoS ACLs
LAN PHY and WAN PHY

32. What is WWDM?
Wide-Wavelength Division Multiplexing
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
10 km
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing

33. What is MLS?
SC or MT-RJ
Value - Mask - and Result (VMR)
Switch(config)#errdisable detect cause rootguard
Multilayer Switching

34. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Switch(config)#errdisable detect cause l2ptguard
Static access or dynamic
40 km
The Drop adjacency

35. What are the administrative modes of Layer 2 switched interfaces?
Content-Addressable Memory
LAN PHY and WAN PHY
Switch(config)#errdisable detect cause bpduguard
Static access - trunk - tunnel or dynamic

36. What are the default error-disable detection causes?
Switch(config)#mac address-table aging-time {seconds}
The Discard adjacency
40 km
Enable error-disable for all possible causes

37. What is TCAM?
Switch#show interfaces status
From 30 seconds to 86 -400 seconds (24 hours)
SVI or native routed interface
Ternary Content-Addressable Memory

38. What are the symptoms of a duplex setting mismatch between two ends of a link?
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
Switch(config)#errdisable detect cause gbic-invalid
Slow response times - low throughput - runts and other input errors on the switch ports
10 Gigabit Ethernet over copper CX4 with Infiniband connectors

39. What is TCAM overflow?
Switch(config)#interface range macro {name}
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
R = LAN PHY; W = WAN PHY

40. What is 10GBASE-SR/SW?
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
A three-fold combination of 0 - 1 and X (don't care)
Process the first packet in a traffic flow to determine the destination
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)

41. What is 100BASE-T4?
With a mask value in addition to binary values to decide which keys in a table are relevant
Adjacent MAC address (6 octets); Layer 3 engine MAC address (6 octets); EtherType (2 octets)
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
Compiling Access Control Entries (ACE) into the TCAM table

42. Displays interface configuration information
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
Switch#show running-config interface {interface}
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
IEEE 802.3

43. What is the standard for 10 Gigabit Ethernet (10GbE)?
IEEE 802.3ae
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
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
From 30 seconds to 86 -400 seconds (24 hours)

44. What is the maximum cabling distance for 10GBASE-LX4/LW4?
Switch(config)#errdisable detect cause udld
The switch port falls back to default setting of half duplex
The CEF epoch number
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF

45. Enables error-disable when trunking encapsulation is flapping from one type to another
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
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
Switch(config)#errdisable detect cause dtp-flap
Switch(config)#errdisable detect cause dhcp-rate-limit

46. What are the common cabling specifications for Fast Ethernet?
Institute of Electrical and Electronics Engineers
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

47. What is the maximum cabling distance for Ethernet - Fast Ethernet and Gigabit Ethernet over UTP cabling?
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
Cisco Express Forwarding
Switch#show interfaces status
100 metres

48. Enables error-disable for conditions that trigger unicast flood blocking on a port
Compiling Access Control Entries (ACE) into the TCAM table
Mask bits set to 1 for Value bits of interest and 0 for Value bits that don't matter
Switch(config)#errdisable detect cause unicast-flood
Electromagnetic Interference

49. What is ANSI?
Switch#show adjacency [{interface}] [summary | detail]
American National Standards Institute
IEEE 802.3z
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]

50. Disables a switch port
The CEF epoch number
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Switch(config-if)#shutdown
Distributed CEF (dCEF)