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Computer Networks → Introduction to Computer Networks 35

Submarine cables connect continents using
Undersea fiber optic cables
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PTP in IEEE 1588 achieves accuracy of
Sub-microsecond synchronization
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NTP accuracy over internet is typically
Milliseconds
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GNSS stands for
Global Navigation Satellite System
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RTK GPS provides accuracy of
Centimeter level
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BGP weight is
Cisco-proprietary local attribute (higher = preferred)
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BGP AS path prepending adds own AS number to make path
Less preferred for inbound traffic
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BGP synchronization rule means
BGP should be synced with IGP before advertising (obsolete)
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EIGRP uses which protocol number
88
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RIP version 2 supports
Classless routing VLSM and authentication
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IS-IS routing protocol type is
Link state
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IS-IS runs over
Its own protocol directly over data link
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ARP spoofing associates attacker MAC with
Legitimate IP of another host
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DAI stands for
Dynamic ARP Inspection
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IP Source Guard uses
DHCP snooping table to allow only legitimate IP/MAC bindings
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BPDU Guard triggers on
BPDU received on PortFast port
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Root Guard prevents
Unauthorized switch becoming root bridge
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MAC flooding attack fills switch MAC table to force
Hub mode (broadcast all frames)
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Storm control limits rate of
Broadcast multicast and unicast floods
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Port security limits
Number of MAC addresses learned per port
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MPLS pipe mode means IP TTL
Not decremented inside tunnel (hidden from traceroute)
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MPLS uniform mode means IP TTL is
Copied to MPLS label and updated at each hop
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MPLS FRR target recovery time is
Sub-50 ms
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RSVP-TE is used to establish
MPLS TE tunnels with bandwidth reservation
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VPLS stands for
Virtual Private LAN Service
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Pseudowire emulates
Layer 2 circuit over packet-switched network
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VRF allows
Multiple independent routing tables on same router
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Route target in L3VPN controls
Import and export of routes between VRFs
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MPLS entropy label improves
ECMP load balancing across LSPs
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AToM stands for
Any Transport over MPLS
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Docker is used for
Container creation and management
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Kubernetes pod is
Smallest deployment unit with one or more containers
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Kubernetes ClusterIP is
Internal cluster IP for service within cluster
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Kubernetes NodePort exposes service on
Static port on every node
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Kubernetes ingress manages
External HTTP/HTTPS routing to services
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Computer Networks → Routing Algorithms 3

OSPF Type 4 LSA is
ASBR Summary LSA
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OSPF uses which protocol number
89
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OSPF virtual link connects
Non-backbone area to area 0 through transit area
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Computer Networks → Application Layer 1

DHCP snooping prevents
Unauthorized DHCP servers on network
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Computer Networks → Switching Techniques 1

VLAN hopping attack exploits
Trunking protocol vulnerabilities to access other VLANs
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