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. What is TCAM?
Cisco Express Forwarding
Creating the VLAN
The Null adjacency
Ternary Content-Addressable Memory

2. Displays interface configuration information
Switch(config)#errdisable detect cause arp-inspection
Switch#show running-config interface {interface}
The CEF epoch number
Trunk or dynamic

3. What is the standard for Fast Ethernet (100 Mbps)?
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
Tunnel
IEEE 802.3u
300 seconds

4. What changes are made to packets by the CEF packet rewrite engine just before forwarding?
Switch#show errdisable recovery
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
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Static access

5. What is the TCAM Value and Mask for an IP access list?
LC - MT-RJ or RJ-45
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
300 seconds
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)

6. Enables error-disable when an interface has been looped back
10GbE operates only at full duplex
UTP Fast Ethernet and Gigabit Ethernet
Switch(config)#errdisable detect cause loopback
Forwarding Information Base

7. What is the name of physical network segment where data packets can collide with one another when being sent?
Collision domain
Switch(config)#errdisable detect cause bpduguard
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
25 metres

8. What CEF adjacency is used when packets must be sent to the Layer 3 engine for further processing?
Switch(config)#interface {type}{module}/{number}
Switch(config)#errdisable detect cause link-flap
The Punt adjacency
Switch#show interfaces {interface} switchport

9. What is EMI?
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
Electromagnetic Interference
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
SVI

10. Enables error-disable detection
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Switch(config)#errdisable detect cause {all | {cause-name}}
Security and QoS ACLs
Packets that have been truncated before they were fully received

11. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Switch(config)#errdisable detect cause l2ptguard
Slow response times - low throughput - runts and other input errors on the switch ports
Creating the VLAN
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]

12. 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)
Switch(config)#default interface {interface}
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
Switch#show errdisable recovery

13. What type of packets can not be forwarded by CEF but are instead sent to the switch CPU for process switching in software?
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
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
1000BASE-T full duplex followed by 1000BASE-T half duplex
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing

14. What RJ-45 pins have been swapped in a Category 5 UTP crossover cable for Fast Ethernet?
1 -2 on one end with 3 -6 on the other end
Switch(config)#errdisable detect cause dhcp-rate-limit
10 km
Interconnecting switches in a campus network

15. What is the name of the switching technology where good frames are received - stored for inspection and then forwarded?
Switch#show errdisable recovery
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
100 metres
Store-and-forward

16. What is the default duplex mode of a Gigabit Ethernet interface?
IEEE 802.3u
Switch(config)#errdisable detect cause dtp-flap
Full duplex
Collision domain

17. What is 10GBASE-CX4?
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
Switch#show cef drop
Switch(config)#errdisable detect cause udld

18. Enables automatic re-enabling of error-disabled ports
Switch(config)#errdisable recovery cause {all | {cause-name}}
IEEE 802.3ab
Tunnel
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)

19. What connectors can be used with SFP modules?
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
LC - MT-RJ or RJ-45
Switch(config)#errdisable detect cause l2ptguard
Manually by administratively disabling and re-enabling the port

20. What CEF optimisation replicates the entire FIB table among switch line cards?
Switch#show errdisable recovery
A station must wait its turn to transmit; it can't transmit and receive at the same time
Static access or trunk
Distributed CEF (dCEF)

21. What is the name of a Layer 3 logical interface on a switch that represents an entire VLAN?
Half duplex
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause link-flap
SVI

22. Enables error-disable for rate-limiting of DHCP snooping
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
Switch(config)#errdisable detect cause dhcp-rate-limit
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP
IEEE 802.3

23. What information is stored in CAM?
Partition and tune the TCAM on some Catalyst switches into areas for different functions
The table of learned MAC addresses - ports - and VLAN information
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
Slow response times - low throughput - runts and other input errors on the switch ports

24. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Switch#show ip cef {interface} [detail]
Collision domain
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP

25. What are the common cabling specifications for Fast Ethernet?
100 metres
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
The Layer 3 engine
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling

26. Adds a description to an interface configuration
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)
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)
Forwarding Information Base
Switch(config-if)#description {string}

27. What are the Gigabit Ethernet autonegotiation selection priorities?
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
1000BASE-T full duplex followed by 1000BASE-T half duplex
Only temporarily for debugging purposes
Switch(config)#interface vlan {vlan-id}

28. What is the original standard for Ethernet (10 Mbps)?
IEEE 802.3
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)
Switch(config)#errdisable recovery cause {all | {cause-name}}
400 metres half duplex and 2000 metres full duplex

29. What is full duplex operation?
Switch#show ip cef
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Switch(config)#errdisable detect cause dtp-flap
300 seconds

30. What are the duplex modes of a GigaStack GBIC?
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used
SVI
The CEF entry version number

31. What is the default duplex mode of a 10 Mbps Ethernet interface?
Switch(config)#errdisable detect cause psecure-violation
Configure the appropriate values manually on both ends of the link
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Half duplex

32. What is 1000BASE-ZX?
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link
Tunnel

33. What is the maximum cabling distance for 10GBASE-ER/EW?
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause l2ptguard
40 km
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

34. What CEF adjacency is used to discard packets because of access list or other policy action?
Switch#show adjacency [{interface}] [summary | detail]
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
The Discard adjacency
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

35. What is an interface-range macro?
IEEE 802.3ae
1000BASE-T full duplex followed by 1000BASE-T half duplex
A name assigned to a ranges of interfaces
Collision domain

36. What is the TCAM Value and Mask for an IPX access list?
Switch(config)#errdisable detect cause ilpower
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
The Layer 3 engine
Interconnecting with existing Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) networks

37. Enables error-disable when a storm control threshold has been exceeded on a port
Switch(config)#errdisable detect cause storm-control
LC - MT-RJ or RJ-45
Switch(config)#errdisable detect cause l2ptguard
Accelerated CEF (aCEF)

38. Disables a switch port
Switch(config-if)#shutdown
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch#show adjacency [{interface}] [summary | detail]
Configure the appropriate values manually on both ends of the link

39. Displays switch port information for a specified interface
Switch#show interfaces {interface} switchport
Switch#show adjacency [{interface}] [summary | detail]
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
Switch(config)#interface {type}{module}/{number}

40. What is the maximum cabling distance for 1000BASE-ZX?
70 km for 9 micron SMF; 100 km for 8 micron SMF
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
Switch(config)#errdisable detect cause udld
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)

41. Adds a static entry to the MAC address table
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance
Switch(config-if)#shutdown
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]

42. What is CEF?
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Cisco Express Forwarding
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
400 metres half duplex and 2000 metres full duplex

43. Displays static CAM table entries
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show interfaces {interface}
Full duplex
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]

44. Enables error-disable for conditions that trigger port security configured on a port
1000BASE-T full duplex followed by 1000BASE-T half duplex
100 metres
Switch(config)#errdisable detect cause psecure-violation
CEF glean

45. How is link speed determined on Fast Ethernet links configured to autonegotiate?
IEEE 802.3u
The table of learned MAC addresses - ports - and VLAN information
Switch(config)#errdisable detect cause ilpower
By electrical signalling so that either end of a link can determine what speed the other end is trying to use

46. What denotes the number of times a CEF entry has been updated since the CEF table was created?
Trunk or dynamic
Static access - trunk - tunnel or dynamic
The CEF entry version number
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

47. 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
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state

48. What is the maximum cabling distance for Ethernet - Fast Ethernet and Gigabit Ethernet over UTP cabling?
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF
Switch(config)#errdisable detect cause l2ptguard
100 metres
Switch#show adjacency [{interface}] [summary | detail]

49. What are GigaStack GBICs used for?
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
Ingress queueing; Destination MAC lookup (CAM); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Egress queueing
When there are more access list entries and Layer 4 operations than available Mask/Value and LOU entries
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]

50. What is LOU?
Full duplex
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Logical Operation Unit
Switch(config)#mac address-table aging-time {seconds}