About This Flashcard Deck
This flashcard deck contains 10 cards covering key Infrastructure concepts for the ENCOR exam. Test your enterprise infrastructure knowledge for ENCOR. Use active recall by attempting to answer each question before revealing the answer.
Question
What are the OSPF LSA types 1 through 5?
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Answer
1=Router, 2=Network (DR), 3=Summary (ABR), 4=ASBR Summary (ABR), 5=External (ASBR).
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All Infrastructure Flashcards
Q: What are the OSPF LSA types 1 through 5?
A: 1=Router, 2=Network (DR), 3=Summary (ABR), 4=ASBR Summary (ABR), 5=External (ASBR).
Q: What is EIGRP DUAL algorithm?
A: Diffusing Update Algorithm — calculates loop-free backup routes. Successor = best route. Feasible Successor = backup route meeting feasibility condition (RD < FD of successor).
Q: What is the BGP path selection tiebreaker order (first 4)?
A: 1. Highest Weight. 2. Highest Local Preference. 3. Locally originated. 4. Shortest AS-path.
Q: What is VXLAN?
A: Virtual Extensible LAN — encapsulates Layer 2 frames in UDP (port 4789) to extend L2 over L3 infrastructure. Uses 24-bit VNI (16M segments vs 4K VLANs).
Q: What is the difference between HSRP, VRRP, and GLBP?
A: HSRP: Cisco proprietary, active/standby. VRRP: open standard, master/backup. GLBP: Cisco, active-active load balancing across gateways.
Q: What is CoPP?
A: Control Plane Policing — rate-limits traffic destined to the router CPU to protect against DoS attacks targeting the control plane.
Q: What is an OSPF stub area?
A: An area that does not accept Type 5 (external) LSAs. The ABR injects a default route instead. Reduces LSDB size and SPF calculations.
Q: What is PIM Sparse Mode?
A: Protocol Independent Multicast — uses a Rendezvous Point (RP). Sources register with RP, receivers join via IGMP. Builds shared trees then optionally shortest-path trees.
Q: What is MACsec (802.1AE)?
A: Layer 2 hop-by-hop encryption that provides confidentiality, integrity, and origin authentication for Ethernet frames.
Q: What is VRF-lite?
A: Creates multiple routing table instances on a single router without MPLS. Used for network segmentation (e.g., guest vs corporate traffic).
Cisco Flashcard Study Strategy
Cisco exams heavily test protocol operations and configuration details. Use these flashcards to drill port numbers, protocol behaviours, and administrative distances. Pair flashcard sessions with Packet Tracer labs — when you encounter a card about OSPF neighbour states, open a lab and verify each state transition on a live topology. This combination of memorisation and practice builds the deep understanding Cisco exams demand.