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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. How are the TCAM Mask/Value pairs evaluated?
In parallel revealing the best (longest) match in a single table lookup
Carrier Sense Multiple Access Collision Detection
Cisco Express Forwarding
Fast Ethernet over 2 pairs EIA/TIA Category 5 UTP

2. Specifies the timer for automatic re-enabling of error-disabled ports
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
Only temporarily for debugging purposes
Switch(config)#errdisable recovery interval {seconds}

3. What are the letters used with 10GBASE-X two-letter suffixes to specify the transceiver wavelengths?
Off
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state
S = Short; L = Long; E = Extra-long

4. What is the operational mode of a switch port that carries transparent Layer 2 VPNs?
Tunnel
The CEF entry version number
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Switch(config)#errdisable detect cause pagp-flap

5. Sets the speed of a Fast Ethernet or Gigabit Ethernet interface
Switch(config-if)#speed {10 | 100 | 1000 | auto}
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
15 metres
Creating the VLAN

6. Enables error-disable for errors when assigning a port to a dynamic VLAN through a VMPS
Native routed interface
Switch(config)#errdisable detect cause vmps
CEF punt
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]

7. What is the name of the CEF engine that maintains routing information in software?
The Layer 3 engine
Switch(config)#errdisable detect cause gbic-invalid
10GbE operates only at full duplex
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)

8. Configures the maximum ageing time for entries in the MAC address table
The Drop adjacency
Switch(config)#mac address-table aging-time {seconds}
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
550 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF

9. What is the name of physical network segment where data packets can collide with one another when being sent?
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)
Collision domain
Feature Manager (FM) and Switching Database Manager (SDM)
Full duplex if only one of the two stacking connectors is used; Half duplex over a shared bus if if both connectors are used

10. What happens to subsequent packets destined for FIB entries in CEF glean state?
Cabling specification for 10 Mbps Ethernet over Unshielded Twisted Pair (UTP) cabling
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)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
They are dropped (ARP throttling)

11. What is 1000BASE-LX/LH?
Switch(config)#errdisable detect cause link-flap
Full duplex
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF or 9 micron SMF (1300 nm laser)

12. What Ethernet ports allow for autonegotiation?
Switch#show interfaces {interface} switchport
Switch(config)#mac address-table aging-time {seconds}
Electromagnetic Interference
UTP Fast Ethernet and Gigabit Ethernet

13. Enables error-disable for errors with offering inline power
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
Institute of Electrical and Electronics Engineers
Switch#show cef not-cef-switched
Switch(config)#errdisable detect cause ilpower

14. What is the TCAM Value and Mask for an extended IP access list using TCP/UDP?
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
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 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. What are the operational modes of a Layer 2 switched interface?
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
SC fibre optic or RJ-45 UTP
Switch#show mac address-table static [address {mac-address}] [interface {interface}] [vlan {vlan}]
Down - static access - trunk or tunnel

16. What is the maximum cabling distance for 1000BASE-CX?
25 metres
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
When one station transmits at the same time as another on a shared medium
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP

17. When do collisions occur?
When one station transmits at the same time as another on a shared medium
70 km for 9 micron SMF; 100 km for 8 micron SMF
Logical Operation Unit
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)

18. What is 10GBASE-SR/SW?
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
Switch(config)#errdisable recovery cause {all | {cause-name}}
A switch port that has been shut down automatically due to a serious error condition
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)

19. What is LOU?
In parallel revealing the best (longest) match in a single table lookup
A three-fold combination of 0 - 1 and X (don't care)
Only temporarily for debugging purposes
Logical Operation Unit

20. How are ports that are in error-disable state re-enabled by default?
Manually by administratively disabling and re-enabling the port
Partition and tune the TCAM on some Catalyst switches into areas for different functions
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
Switched virtual interface (SVI)

21. What are the classes of Physical Media Dependent (PMD) interfaces defined by IEEE 802.3ae?
LC - MT-RJ or RJ-45
XENPAK - X2 - or SFP+
LAN PHY and WAN PHY
SVI

22. What fields are rewritten in hardware before a Layer 3 packet is switched to the to egress queue of a multilayer switch?
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
Switch(config)#errdisable detect cause udld
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
Switch(config)#interface {type}{module}/{number}

23. Displays the CAM table size with number of MAC addresses
The Null adjacency
CEF punt
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause arp-inspection

24. Displays entries in the Forwarding Information Base (FIB) for a specific subnet
Off
Static access or trunk
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
Tunnel

25. What CEF optimisation replicates the entire FIB table among switch line cards?
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
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
The Drop adjacency
Distributed CEF (dCEF)

26. Enables error-disable when an STP BPDU is received from a root bridge on an unexpected port
300 seconds
Store-and-forward
Switch(config)#errdisable detect cause rootguard
Switch(config-if)#switchport mode access

27. How is link speed determined on Fast Ethernet links configured to autonegotiate?
Switch(config)#errdisable detect cause security-violation
By electrical signalling so that either end of a link can determine what speed the other end is trying to use
Source IP (/32) - Destination IP (/32) - Protocol (/16) - IP ToS (/8) - Source port (/16) - Source operator (/4) - Destination port (/16) - Destination operator (/4)
Switch(config)#errdisable detect cause pagp-flap

28. What is the operational mode of a switch port that uses DTP negotiation?
Static access or trunk
Switch(config)#errdisable detect cause bpduguard
Switch(config-if)#description {string}
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)

29. What information is stored in CAM?
The table of learned MAC addresses - ports - and VLAN information
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
Switch#show interfaces {interface}
When the Spanning Tree Protocol (STP) has put the switch port in learning or forwarding state

30. What is the TCAM Value and Mask for an Ethernet access list?
Switch(config-if)#duplex {auto | full | half}
Source MAC (/48); Destination MAC (/48); Ethertype (/16)
Switch(config-if)#switchport access vlan {vlan}
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

31. What is the role of a Route Processor (RP) in first generation MLS?
Process the first packet in a traffic flow to determine the destination
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]
Switch#show interfaces {interface} switchport
Switch(config)#errdisable detect cause vmps

32. What are the 100BASE-FX connectors used in Cisco Catalyst switches?
Switch(config)#errdisable detect cause dtp-flap
SC or MT-RJ
10 Gigabit Ethernet over 9 micron SMF (1310 nm serial laser)
IEEE 802.3ab

33. What is a GigaStack GBIC?
Trunk
IEEE 802.3u
300 seconds
A proprietary connector with a high-data-rate copper cable with enhanced signal integrity and EMI performance

34. Enables error-disable for errors with Layer 2 Protocol Tunnelling
Switch(config)#errdisable detect cause l2ptguard
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Enable error-disable for all possible causes

35. Displays dynamic CAM table entries
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause vmps
Switch(config)#errdisable detect cause unicast-flood
10 km

36. What is error-disable state?
Accelerated CEF (aCEF)
A switch port that has been shut down automatically due to a serious error condition
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]

37. What is CSMA/CD?
Forwarding Information Base
Switch(config)#errdisable detect cause psecure-violation
Carrier Sense Multiple Access Collision Detection
Switch#show interfaces {interface}

38. What technology was merged into the IEEE 802.3 Ethernet standard to create Gigabit Ethernet?
American National Standards Institute
ANSI X3T11 FibreChannel
XENPAK - X2 - or SFP+
Bundling together two to eight full duplex Fast Ethernet links to act as a single physical link

39. Displays entries in the Forwarding Information Base (FIB) for a specific interface
On
Switch#show ip cef {interface} [detail]
10 km
The Null adjacency

40. What are the default error-disable detection causes?
Static access or trunk
IEEE 802.3
Fast Ethernet over 62.5/125 micron multimode fibre (MMF) or 9 micron singlemode fibre (SMF)
Enable error-disable for all possible causes

41. Enables error-disable when an interface has been looped back
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause loopback
Switch(config)#default interface {interface}
Enable error-disable for all possible causes

42. Sets the duplex mode of an Ethernet or Fast Ethernet interface
Through exchange of information - which means that for one end to successfully negotiate duplex mode the other end must also be set to autonegotiate
IEEE 802.3
Half duplex
Switch(config-if)#duplex {auto | full | half}

43. What is 1000BASE-T?
FIB with adjacency table
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
Switch#show interfaces status err-disabled
Flooding a frame with unknown destination MAC address out all ports assigned to the source port VLAN except the source port itself

44. What information is stored in TCAM?
On
Security and QoS ACLs
Only temporarily for debugging purposes
Institute of Electrical and Electronics Engineers

45. What is EMI?
1 -2 on one end with 3 -6 on the other end
Dynamic
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
Electromagnetic Interference

46. What are the common cabling specifications for Fast Ethernet?
UTP Fast Ethernet and Gigabit Ethernet
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX
Dynamic
Switch#show ip cef {network} [{mask}] [longer-prefixes] [detail]

47. What CEF adjacency is used to switch packets that can't be forwarded normally?
Native routed interface
The Drop adjacency
Only temporarily for debugging purposes
Static access

48. What is 1000BASE-X?
LOU registers
Cabling specifications for Gigabit Ethernet
10 km
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)

49. Enables error-disable for Bridge Protocol Data Units (BPDU) received on ports configured for STP PortFast
With a mask value in addition to binary values to decide which keys in a table are relevant
IEEE 802.3
Switch(config)#errdisable detect cause bpduguard
10 Gigabit Ethernet over 9 micron SMF (1550 nm serial laser)

50. What is 100BASE-T4?
Fast Ethernet over 4 pairs EIA/TIA Category 3 - 4 - 5 UTP
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance
SVI
Switch#show adjacency [{interface}] [summary | detail]