Test your basic knowledge |

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 static CAM table entries
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Native routed interface
Process the first packet in a traffic flow to determine the destination

2. What is the TCAM Value and Mask for an IGMP access list?
Collision domain
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)
The Punt adjacency
Value - Mask - and Result (VMR)

3. What Ethernet ports allow for autonegotiation?
Switch(config-if)#description {string}
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
UTP Fast Ethernet and Gigabit Ethernet
Switch#show interfaces status

4. Displays entries in the Forwarding Information Base (FIB) for a specific subnet
Trunk or dynamic
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
LOU registers
Full duplex only

5. What is 1000BASE-SX?
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
SC or MT-RJ
On

6. What denotes the number of times a CEF entry has been updated since the CEF table was created?
The CEF entry version number
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}

7. When can a switch start to learn source MAC addresses on incoming ports?
Route caching and topology based
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
Switch#show running-config interface {interface}
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state

8. Displays a list with status of all interfaces
Switch(config)#interface range macro {name}
Static access or dynamic
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Switch#show interfaces status

9. What is 10GBASE-SR/SW?
LC - MT-RJ or RJ-45
Trunk or dynamic
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
1000BASE-T full duplex followed by 1000BASE-T half duplex

10. What information is stored in CAM?
The table of learned MAC addresses - ports - and VLAN information
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
IEEE 802.3z
Switch(config)#errdisable detect cause vmps

11. What are the letters used with 10GBASE-X two-letter suffixes to specify the PHY type?
R = LAN PHY; W = WAN PHY
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch#show interfaces {interface} switchport

12. What are the 10GBASE-X PMD transceiver form factors used in Cisco Catalyst switches?
Switch(config)#default interface {interface}
Switch(config-if)#speed {10 | 100 | 1000 | auto}
XENPAK - X2 - or SFP+
The Drop adjacency

13. What is the administrative mode of a switch port that is a member of one VLAN?
70 km for 9 micron SMF; 100 km for 8 micron SMF
Switch#show running-config interface {interface}
Static access or dynamic
SVI or native routed interface

14. What is 10GBASE-LR/LW?
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Native routed interface
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)

15. What is CEF?
The switch port falls back to default setting of half duplex
Wide-Wavelength Division Multiplexing
Cisco Express Forwarding
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}

16. What is EMI?
Static access - trunk - tunnel or dynamic
SC fibre optic or RJ-45 UTP
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
Electromagnetic Interference

17. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
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
In parallel revealing the best (longest) match in a single table lookup
The Punt adjacency
With a mask value in addition to binary values to decide which keys in a table are relevant

18. What is IEEE?
Institute of Electrical and Electronics Engineers
The switch port falls back to default setting of half duplex
25 metres
Security and QoS ACLs

19. Displays error-disabled recovery timer information
Switch#show errdisable recovery
The Discard adjacency
Source MAC address; Port of arrival; VLAN; Time stamp
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance

20. What denotes the number of times the CEF table has been flushed and regenerated as a whole?
The CEF epoch number
1000BASE-T full duplex followed by 1000BASE-T half duplex
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing

21. What is 100BASE-T2?
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
Down - static access - trunk or tunnel
The Discard adjacency
LC - MT-RJ or RJ-45

22. Enables error-disable when the Port Aggregation Protocol (PAgP) is flapping
Switch(config)#errdisable detect cause pagp-flap
Packets that have been truncated before they were fully received
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
In TCAM Value entries

23. What are runts?
A station must wait its turn to transmit; it can't transmit and receive at the same time
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
Packets that have been truncated before they were fully received

24. What is the standard for Fast Ethernet (100 Mbps)?
Collision domain
With a mask value in addition to binary values to decide which keys in a table are relevant
In TCAM Value entries
IEEE 802.3u

25. What is the default duplex mode of a Fast Ethernet interface?
Switched virtual interface (SVI)
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Half duplex
Routing table and ARP table

26. What are the Gigabit Ethernet autonegotiation selection priorities?
1000BASE-T full duplex followed by 1000BASE-T half duplex
American National Standards Institute
Switch(config-if)#no switchport
In parallel revealing the best (longest) match in a single table lookup

27. What are the common cabling specifications for Gigabit Ethernet?
15 metres
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Static access or trunk
The Punt adjacency

28. Disables CEF operation on an interface
Switch(config-if)#no ip route-cache cef
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
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

29. What is the state of packets that are sent to the CEF Layer 3 engine because of missing Layer 2 next-hop addresses?
40 km
Switch(config)#errdisable detect cause dhcp-rate-limit
CEF glean
Collision domain

30. What CEF adjacency is used to switch packets destined for the null interface?
The Null adjacency
SC fibre optic or RJ-45 UTP
IEEE 802.3ab
Source MAC (/48); Destination MAC (/48); Ethertype (/16)

31. What is the maximum cabling distance for 1000BASE-ZX?
Partition and tune the TCAM on some Catalyst switches into areas for different functions
70 km for 9 micron SMF; 100 km for 8 micron SMF
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Multilayer Switching

32. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
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
10 km
Switch(config)#errdisable recovery cause {all | {cause-name}}
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding

33. What is the default duplex mode of a Gigabit Ethernet interface?
Full duplex
Switch#show interfaces {interface}
100 metres
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)

34. What are the symptoms of a duplex setting mismatch between two ends of a link?
Switch(config)#errdisable recovery interval {seconds}
SVI or native routed interface
Slow response times - low throughput - runts and other input errors on the switch ports
Switch(config)#interface vlan {vlan-id}

35. What is the DTP negotiation mode of a switch port configured as dynamic?
Switch(config)#errdisable detect cause l2ptguard
On
Switch(config)#errdisable detect cause security-violation
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error

36. What portion of the FIB contains the Layer 3 next-hop addresses for each entry together with the corresponding Layer 2 information?
The Punt adjacency
A three-fold combination of 0 - 1 and X (don't care)
Switch(config)#errdisable detect cause link-flap
The adjacency table

37. How is link speed determined on Fast Ethernet links configured to autonegotiate?
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Switch(config)#errdisable detect cause pagp-flap
By electrical signalling so that either end of a link can determine what speed the other end is trying to use

38. What is a SVI?
FIB with adjacency table
Switched virtual interface (SVI)
10 km
Trunk or dynamic

39. What are the administrative modes of Layer 2 switched interfaces?
Switch(config-if)#switchport access vlan {vlan}
Static access - trunk - tunnel or dynamic
Tunnel
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions

40. What CEF adjacency is used to switch packets that can't be forwarded normally?
American National Standards Institute
Switch(config-if)#no ip route-cache cef
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
The Drop adjacency

41. What is the name of a Layer 3 logical interface on a switch that represents an entire VLAN?
SVI
Store-and-forward
Route caching and topology based
10GbE operates only at full duplex

42. What is the TCAM Value and Mask for an IP access list?
Store-and-forward
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
10 km
Switch#show cef drop

43. Configures a switch port with a static access VLAN assignment
Switch(config-if)#switchport access vlan {vlan}
Switch#show interfaces status err-disabled
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
Switch(config)#errdisable detect cause dhcp-rate-limit

44. Enables error-disable for conditions that trigger unicast flood blocking on a port
Creating the VLAN
Switch(config)#errdisable detect cause gbic-invalid
Switch(config)#errdisable detect cause unicast-flood
Carrier Sense Multiple Access Collision Detection

45. What is 10GBASE-ER/EW?
Configure the appropriate values manually on both ends of the link
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
SC or MT-RJ
Switch(config)#errdisable detect cause loopback

46. Where is source and destination addresses and other relevant protocol information for access lists stored in the TCAM table?
In TCAM Value entries
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
66-300 metres for 50 micron MMF; 33 metres for 62.5 micron MMF

47. What are the default error-disable detection causes?
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding
Switch(config)#errdisable detect cause psecure-violation
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
Enable error-disable for all possible causes

48. What is the DTP negotiation mode of a switch port configured as trunk?
A switch port that has been shut down automatically due to a serious error condition
On
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
Feature Manager (FM) and Switching Database Manager (SDM)

49. 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
The Punt adjacency
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
The Layer 3 forwarding engine

50. What is the TCAM Value and Mask for an ICMP access list?
Source IP (/32); Destination IP (/32); Protocol (/16); ICMP code (/8); ICMP type (/4); IP type of service (ToS) (/8)
Switch(config)#errdisable recovery interval {seconds}
10 km
Static access or trunk