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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 CEF?
Cisco Express Forwarding
Native routed interface
Switch(config-if)#switchport access vlan {vlan}
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

2. What is the prerequesite for creating a working SVI?
SVI or native routed interface
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Creating the VLAN
LOU registers

3. Enables error-disable for errors with dynamic ARP inspection
Switch(config-if)#speed {10 | 100 | 1000 | auto}
Switch(config-if)#switchport access vlan {vlan}
Switch(config)#errdisable detect cause arp-inspection
Ternary Content-Addressable Memory

4. What information is recorded in CAM as frames arrive on a switch port?
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Content-Addressable Memory
Source MAC address; Port of arrival; VLAN; Time stamp
Switch(config-if)#switchport mode access

5. What is the maximum cabling distance for 10GBASE-CX4?
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Switch(config)#errdisable detect cause udld
15 metres
The Punt adjacency

6. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Switch#show ip cef {interface} [detail]
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switched virtual interface (SVI)
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries

7. What is 10BASE-T?
IEEE 802.3u
On
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
Collision domain

8. What CEF adjacency is used to discard packets because of access list or other policy action?
Trunk
Security and QoS ACLs
The Discard adjacency
The Null adjacency

9. Displays interface configuration information
Switch(config-if)#no switchport
Collision domain
Routing table and ARP table
Switch#show running-config interface {interface}

10. What is the operational mode of a switch port that is a member of one VLAN?
Static access or dynamic
Switch(config)#errdisable detect cause gbic-invalid
Static access
Switch#show errdisable detect

11. Enables error-disable when an interface has been looped back
Switch(config)#mac address-table aging-time {seconds}
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
Switch(config)#errdisable detect cause loopback
IEEE 802.3u

12. What connectors can be used with SFP modules?
LC - MT-RJ or RJ-45
American National Standards Institute
40 km
Static access or trunk

13. What is MLS?
Multilayer Switching
Switch(config-if)#shutdown
Switch(config)#interface {type}{module}/{number}
The Layer 3 forwarding engine

14. What mechanism does the TCAM provide for Layer 4 comparisons involving gt - lt - neq or range operators?
On
IEEE 802.3
LOU registers
Switch(config)#errdisable detect cause channel-misconfig

15. What tables are maintained by the CEF Layer 3 engine?
Switch#show interfaces {interface}
Switch(config)#interface vlan {vlan-id}
Routing table and ARP table
IEEE 802.3ae

16. When do collisions occur?
CEF glean
When one station transmits at the same time as another on a shared medium
Process the first packet in a traffic flow to determine the destination
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]

17. What is the name of the CEF engine that maintains routing information in software?
The Layer 3 engine
Mask bits set to 1 for Value bits of interest and 0 for Value bits that don't matter
1 -2 on one end with 3 -6 on the other end
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)

18. Displays static CAM table entries
Switch(config)#errdisable detect cause ilpower
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch(config)#interface vlan {vlan-id}

19. What is error-disable state?
A switch port that has been shut down automatically due to a serious error condition
70 km for 9 micron SMF; 100 km for 8 micron SMF
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
Static access or trunk

20. What is the name of the CEF engine that forwards packets in hardware?
The Layer 3 forwarding engine
LAN PHY and WAN PHY
R = LAN PHY; W = WAN PHY
The Drop adjacency

21. What is the maximum cabling distance for 10GBASE-LX4/LW4?
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
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
The Discard adjacency
S = Short; L = Long; E = Extra-long

22. How are packets marked before being sent to the CEF Layer 3 engine for further processing?
CEF punt
Static access or trunk
In parallel revealing the best (longest) match in a single table lookup
15 metres

23. How is link speed determined on Fast Ethernet links configured to autonegotiate?
10 km
Half duplex
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
Security and QoS ACLs

24. What information is stored in TCAM?
Switch(config)#no ip cef
Security and QoS ACLs
Wide-Wavelength Division Multiplexing
Store-and-forward

25. What is a SVI?
Switched virtual interface (SVI)
Forwarding Information Base
The Discard adjacency
Switch(config)#errdisable detect cause rootguard

26. What is the administrative mode of a switch port that carries traffic for multiple VLANs?
Trunk or dynamic
Switch(config)#errdisable detect cause dtp-flap
Institute of Electrical and Electronics Engineers
The Drop adjacency

27. What information is stored in CAM?
Cabling specifications for Gigabit Ethernet
SC fibre optic or RJ-45 UTP
Wide-Wavelength Division Multiplexing
The table of learned MAC addresses - ports - and VLAN information

28. Specifies the timer for automatic re-enabling of error-disabled ports
Mask bits set to 1 for Value bits of interest and 0 for Value bits that don't matter
Slow response times - low throughput - runts and other input errors on the switch ports
Switch(config)#errdisable recovery interval {seconds}
300 seconds

29. What is the default duplex mode of a 10 Mbps Ethernet interface?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
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
Half duplex
Store-and-forward

30. What is WAN PHY used for?
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show errdisable recovery
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)

31. What is CSMA/CD?
By Mask/Value - where each unique mask has eight value patterns associated with it
In parallel revealing the best (longest) match in a single table lookup
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Carrier Sense Multiple Access Collision Detection

32. What is the default timer for automatic re-enabling of error-disabled ports?
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Slow response times - low throughput - runts and other input errors on the switch ports
Switch(config-if)#no switchport
300 seconds

33. What is an interface-range macro?
A name assigned to a ranges of interfaces
Switch#show interfaces status err-disabled
IEEE 802.3ae
IEEE 802.3u

34. What is the administrative mode of a switch port that uses DTP to negotiate its operational mode?
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
1000BASE-T full duplex followed by 1000BASE-T half duplex
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
Dynamic

35. What is LAN PHY used for?
XENPAK - X2 - or SFP+
100 metres
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks
Interconnecting switches in a campus network

36. Sets the administrative mode of a switch port to access
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
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
Switch(config-if)#switchport mode access
Switch#show errdisable recovery

37. What type of packets can not be forwarded by CEF but are instead sent to the switch CPU for process switching in software?
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
Configure the appropriate values manually on both ends of the link
Creating the VLAN
Cisco Express Forwarding

38. What are the basic operations that a frame undergoes as it passes through a multilayer switch?
Accelerated CEF (aCEF)
A switch port that has been shut down automatically due to a serious error condition
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Tunnel

39. What is 1000BASE-CX?
15 metres
Manually by administratively disabling and re-enabling the port
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling

40. What is 100BASE-FX?
With a mask value in addition to binary values to decide which keys in a table are relevant
Route caching and topology based
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
The Drop adjacency

41. Enables error-disable for the presence of invalid GBIC or SFP modules
Switch(config)#errdisable detect cause gbic-invalid
S = Short; L = Long; E = Extra-long
Ternary Content-Addressable Memory
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)

42. Enables automatic re-enabling of error-disabled ports
Switch(config-if)#description {string}
Route caching and topology based
Manually by administratively disabling and re-enabling the port
Switch(config)#errdisable recovery cause {all | {cause-name}}

43. How are ternary combinations implemented?
When one station transmits at the same time as another on a shared medium
With a mask value in addition to binary values to decide which keys in a table are relevant
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#show adjacency [{interface}] [summary | detail]

44. What are the 100BASE-FX connectors used in Cisco Catalyst switches?
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
10GbE operates only at full duplex
SC or MT-RJ
Switch(config)#errdisable detect cause dhcp-rate-limit

45. Disables CEF operation globally
Wide-Wavelength Division Multiplexing
Switch(config)#no ip cef
CEF punt
Switch(config)#errdisable detect cause storm-control

46. What is the default duplex mode of a Gigabit Ethernet interface?
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Full duplex
A switch port that has been shut down automatically due to a serious error condition

47. What is a GigaStack GBIC?
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF

48. What is the maximum cabling distance for Fast Ethernet over 62.5/125 micron multimode fibre?
From 30 seconds to 86 -400 seconds (24 hours)
400 metres half duplex and 2000 metres full duplex
300 seconds
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)

49. Displays the entire Forwarding Information Base (FIB)
Switch#show ip cef
Switch(config)#errdisable detect cause storm-control
Content-Addressable Memory
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum

50. What CEF optimisation replicates the entire FIB table among switch line cards?
Switch(config)#errdisable detect cause ilpower
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Distributed CEF (dCEF)
Switch(config)#errdisable detect cause gbic-invalid