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Computer Networks → Introduction to Computer Networks 34

VTP server mode
Can create modify delete VLANs and propagates changes
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VTP client mode
Creates no VLANs but applies updates received
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DTP auto mode
Negotiates trunk if other side is desirable or auto
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DTP desirable mode
Actively attempts to negotiate trunk
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802.1Q tag is inserted after
Source MAC address
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EIGRP hold time is typically
3x hello interval
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EIGRP feasibility condition ensures
Backup route is loop-free
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EIGRP active state occurs when
No feasible successor and router queries neighbors
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EIGRP SIA stands for
Stuck In Active (query not answered in time)
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PTP grandmaster clock provides
Primary time reference for PTP domain
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PTP boundary clock
Acts as slave to master and master to downstream slaves
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PTP transparent clock
Passes PTP but corrects for transit delay
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IEEE 802.1AS is for
Precision time synchronization (generalized PTP)
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White Rabbit protocol provides
Sub-nanosecond synchronization
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GPS 1PPS provides
Sub-microsecond timing reference
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Stratum 0 time source is
Hardware reference clock like atomic or GPS
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Stratum 1 NTP server is
Directly connected to stratum 0 source
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SONET SDH is
Physical optical transport standard
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OTN G.709 adds to SONET SDH
Enhanced OAM FEC and multi-layer client mapping
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LACP PDU is called
LACPDU
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EtherChannel load balancing default is typically
Source and destination MAC XOR
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Stack master in Cisco StackWise handles
Control plane for entire stack
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VSS (Virtual Switching System) creates
Single control plane from two physical switches
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vPC in Nexus creates
Active-active EtherChannel to two different Nexus switches
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MLAG creates
Multi-chassis LAG across two switches
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Jumbo frames are MTU larger than
1518 bytes
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Jumbo frames in data center typically use
9000 bytes
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Baby giant frames are slightly larger than
1518 bytes
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QinQ double-tagged frame overhead per tag is
4 bytes
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Cryptojacking uses victim resources for
Cryptocurrency mining
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Fileless malware operates in
Memory without writing to disk
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Trojan horse malware disguises as
Legitimate useful software
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Worm vs virus difference is
Worm replicates without host file virus needs host
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Rootkit hides at
OS or kernel level
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Computer Networks → Types of Networks 1

EIGRP hello interval on LAN is
default is 5 seconds
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Computer Networks → Routing Algorithms 5

OSPF interface priority 0 means
Cannot become DR or BDR
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OSPF database exchange uses
DBD LSR LSU packets
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OSPF DBD packet does
Describes link state database for synchronization
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OSPF LSR is
Link State Request
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OSPF LSU contains
One or more LSAs for transmission
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