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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
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
Switch(config)#errdisable detect cause ilpower
Source IPX network (/32); Destination IPX network (/32); Destination node (/48); IPX packet type (/16)

2. What is an interface-range macro?
From 30 seconds to 86 -400 seconds (24 hours)
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
Distributed CEF (dCEF)
A name assigned to a ranges of interfaces

3. What is 100BASE-T2?
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)
Only temporarily for debugging purposes
Numeric values that represent what action to take after the TCAM lookup occurs
Fast Ethernet over 2 pairs EIA/TIA Category 3 - 4 - 5 UTP

4. Enables automatic re-enabling of error-disabled ports
Process the first packet in a traffic flow to determine the destination
Static access - trunk - tunnel or dynamic
Switch(config)#errdisable detect cause l2ptguard
Switch(config)#errdisable recovery cause {all | {cause-name}}

5. What are the administrative modes of Layer 2 switched interfaces?
Static access - trunk - tunnel or dynamic
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
IEEE 802.3ae
300 seconds

6. Displays entries in the Forwarding Information Base (FIB) for a specific interface
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
By Mask/Value - where each unique mask has eight value patterns associated with it
Switch(config)#errdisable detect cause ilpower
Switch#show ip cef {interface} [detail]

7. What RJ-45 pins must be swapped in a Category 5 UTP crossover cable for Gigabit Ethernet?
Carrier Sense Multiple Access Collision Detection
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
Switch(config-if)#no ip route-cache cef
The Discard adjacency

8. What is the TCAM Value and Mask for an IP access list?
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8)
Switch(config)#errdisable detect cause {all | {cause-name}}
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
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

9. Creates a switched virtual interface (SVI) and enters interface configuration mode
Switch(config)#interface vlan {vlan-id}
Accelerated CEF (aCEF)
Manually by administratively disabling and re-enabling the port
Half duplex

10. What is the maximum cabling distance for Fast Ethernet over 62.5/125 micron multimode fibre?
Switch(config-if)#switchport access vlan {vlan}
400 metres half duplex and 2000 metres full duplex
Switch(config)#errdisable detect cause {all | {cause-name}}
Per port collision domains; Full duplex mode; Dedicated bandwidth; Error detection; Broadcast thresholds; Intelligent filtering and forwarding

11. What is 10GBASE-X?
ANSI X3T11 FibreChannel
Cabling specifications for 10 Gigabit Ethernet
Feature Manager (FM) and Switching Database Manager (SDM)
The adjacency table

12. What denotes the number of times the CEF table has been flushed and regenerated as a whole?
The CEF epoch number
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
Mask bits set to 1 for Value bits of interest and 0 for Value bits that don't matter

13. Displays CEF Drop statistics with number of packets and reason for each line card
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show cef drop
300 seconds
Switch(config-if)#speed {10 | 100 | 1000 | auto}

14. How does topology based switching work?
Switch#show interfaces status
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
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
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing

15. Enables error-disable for rate-limiting of DHCP snooping
Switch(config)#errdisable detect cause udld
Switch(config)#errdisable detect cause dhcp-rate-limit
Partition and tune the TCAM on some Catalyst switches into areas for different functions
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

16. What changes are made to packets by the CEF packet rewrite engine just before forwarding?
Switch(config)#errdisable detect cause storm-control
Trunk or dynamic
1 -2 on one end with 3 -6 on the other end
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

17. What information is stored in TCAM?
Switch(config)#errdisable recovery cause {all | {cause-name}}
Switch(config)#interface {type}{module}/{number}
Security and QoS ACLs
1 -2 on one end with 3 -6 on the other end

18. Displays the entire Forwarding Information Base (FIB)
Forwarding Information Base
Switch#clear mac address-table [dynamic] [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show ip cef
10 Gigabit Ethernet over 50 or 62.5 micron MMF (850 nm serial laser)

19. What is CSMA/CD?
Switch(config)#errdisable detect cause link-flap
Forwarding Information Base
Carrier Sense Multiple Access Collision Detection
Source IP (/32); Destination IP (/32); Protocol (/16); IP ToS (/8); IGMP message type (/8)

20. What is IEEE?
Switch(config)#errdisable detect cause storm-control
IEEE 802.3ae
Institute of Electrical and Electronics Engineers
Half duplex

21. What information is recorded in CAM as frames arrive on a switch port?
Switch(config-if)#speed {10 | 100 | 1000 | auto}
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 address; Port of arrival; VLAN; Time stamp
Switch(config-if)#switchport mode access

22. Displays a list with status of all interfaces
Switch(config)#errdisable detect cause psecure-violation
Switch#show mac address-table [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch#show interfaces status
Trunk

23. What is error-disable state?
Trunk
A switch port that has been shut down automatically due to a serious error condition
100 metres
100BASE-TX - 100BASE-T2 - 100BASE-T4 and 100-BASE-FX

24. What is the maximum cabling distance for Fast Ethernet over singlemode fibre?
10 km
LOU registers
Switch(config)#errdisable detect cause pagp-flap
10 Gigabit Ethernet over 50 or 62.5 micron MMF or 9 micron SMF (1300 nm WWDM laser)

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

26. What is 10GBASE-LR/LW?
10 Gigabit Ethernet over 9 micron SMF (1310 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
Switch(config)#default interface {interface}
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)

27. What is the standard for Gigabit Ethernet (1000 Mbps)?
SVI or native routed interface
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling
When one station transmits at the same time as another on a shared medium
IEEE 802.3z

28. Enables error-disable for errors related to 802.1x security
Switch(config)#errdisable detect cause security-violation
Switch(config-if)#no ip route-cache cef
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(config)#errdisable detect cause rootguard

29. What are the common PMD types for 10 Gigabit Ethernet?
Accelerated CEF (aCEF) and Distributed CEF (dCEF)
On
Configure the appropriate values manually on both ends of the link
10GBASE-SR/SW - 10GBASE-LR/LW - 10GBASE-ER/EW - 10GBASE-LX4/LW4 - 10GBASE-CX4

30. What are the basic operations that a frame undergoes as it passes through a multilayer switch?
10 Gigabit Ethernet over copper CX4 with Infiniband connectors
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Switch#show running-config interface {interface}
Dynamic

31. What is MLS?
Tunnel
Multilayer Switching
Switch#show mac address-table count [address {mac-address}] [interface {interface}] [vlan {vlan}]
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF

32. Enables error-disable when trunking encapsulation is flapping from one type to another
Switch#show mac address-table dynamic [address {mac-address}] [interface {interface}] [vlan {vlan}]
Switch(config)#errdisable detect cause dtp-flap
1000BASE-T full duplex followed by 1000BASE-T half duplex
The Null adjacency

33. What fields are rewritten in hardware before a Layer 3 packet is switched to the to egress queue of a multilayer switch?
Ingress queueing; Destination MAC lookup (CAM); Destination IP lookup (FIB); Security ACL lookup (TCAM); QoS ACL lookup (TCAM); Layer 3 packet rewrite; Egress queueing
Switch(config-if)#switchport mode access
Layer 2 source and destination MAC addresses; Layer 3 Time-To-Live (TTL) value and header checksum
Switch(config)#errdisable detect cause gbic-invalid

34. How are packets marked before being sent to the CEF Layer 3 engine for further processing?
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
CEF punt
Electromagnetic Interference
GBIC-to-GBIC connection between stacking Catalyst switches or between any two Gigabit switch ports over a short distance

35. What is LAN PHY used for?
Interconnecting switches in a campus network
Cabling specifications for Gigabit Ethernet
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
275 metres for 62.5 micron MMF; 550 metres for 50 micron MMF

36. What happens when autonegotiating of link duplex mode fails on a Fast Ethernet link?
The Discard adjacency
The switch port falls back to default setting of half duplex
CEF glean
Gigabit Interface Converter (GBIC) or Small Form factor Pluggable (SFP)

37. What is the name of a Layer 3 logical interface on a switch that represents an entire VLAN?
SVI
300 seconds
XENPAK - X2 - or SFP+
In parallel revealing the best (longest) match in a single table lookup

38. Displays administrative and operational status for a specified interface
Half duplex
1000BASE-CX - 1000BASE-T - 1000-BASE-SX - 1000-BASE-LX/LH and 1000-BASE-ZX
Partition and tune the TCAM on some Catalyst switches into areas for different functions
Switch#show interfaces {interface}

39. Sets the duplex mode of an Ethernet or Fast Ethernet interface
Distributed CEF (dCEF)
Process the first packet in a traffic flow to determine the destination
Switch(config-if)#duplex {auto | full | half}
Switch(config)#errdisable detect cause dtp-flap

40. How does the IEEE 802.3ae standard differ from its predecessors at the physical layer?
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)
LOU registers
Content-Addressable Memory
10GbE operates only at full duplex

41. Creates an interface-range macro
Switch(config)#errdisable detect cause udld
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
When one station transmits at the same time as another on a shared medium
300 metres for 50 or 62.5 micron MMF; 10 km for 9 micron SMF

42. What is the content of TCAM Result entries?
Wide-Wavelength Division Multiplexing
100 metres
Encapsulation failure; Unresolved address; Unsupported protocol; No valid route; No valid adjacency; Checksum error
Numeric values that represent what action to take after the TCAM lookup occurs

43. What is 1000BASE-ZX?
Gigabit Ethernet over 1 pair 8 or 9 micron SMF (1550 nm laser)
Gigabit Ethernet over 4 pairs EIA/TIA Category 5 UTP
A name assigned to a ranges of interfaces
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

44. What is the default duplex mode of a 10 Mbps Ethernet interface?
Half duplex
Switch(config)#mac address-table static {mac-address} vlan {vlan} interface {interface}
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
Static access

45. Enables error-disable when a link is seen to be unidirectional
Stations can transmit and receive at the same time because switched Ethernet removes the possibility of collisions
Switch(config)#errdisable detect cause dtp-flap
Switch(config)#errdisable detect cause udld
Switch(config)#errdisable detect cause ilpower

46. What is the original standard for Ethernet (10 Mbps)?
They are dropped (ARP throttling)
IEEE 802.3
Switch(config)#errdisable detect cause security-violation
Feature Manager (FM) and Switching Database Manager (SDM)

47. Selects a switch port interface and enters interface configuration mode
Cisco Express Forwarding
Switch(config)#interface {type}{module}/{number}
The Layer 3 forwarding engine
SVI or native routed interface

48. What is 1000BASE-CX?
10 km
400 metres half duplex and 2000 metres full duplex
Switch(config)#no ip cef
Gigabit Ethernet over 1 pair Shielded Twisted Pair (STP) cabling

49. What is the administrative mode of a switch port that uses DTP to negotiate its operational mode?
Switch#show ip cef
Dynamic
XENPAK - X2 - or SFP+
Gigabit Ethernet over 1 pair 50 or 62.5 micron MMF (850 nm laser)

50. What is the maximum cabling distance for 1000BASE-CX?
Switch(config)#interface range {type}{module}/{number} [- {number}] [ - {type}{module}/{number} ...]
UTP Fast Ethernet and Gigabit Ethernet
Switch(config)#define interface-range {macro-name} {type} {module}/{number} [- {number}] [ - {type} {module}/{number} ...]
25 metres