Cisco ENCOR Cheat Sheet 2026

The 30 highest-yield Cisco ENCOR facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What control plane protocol is utilized to map and resolve endpoints in a Cisco SD-Access fabric? → LISP
2. Which command enables TACACS+ as the authentication method for console login on a Cisco IOS device? → aaa authentication login default tacacs+
3. What is the purpose of SNMP traps? → Send asynchronous event notifications from agent to manager
4. After making changes to settings on a switch in CONFIGURATION mode, only the most recent modifications will be implemented. → After you type copy running startup and reboot the switch
5. In EIGRP, what occurs when a router loses its Successor and no Feasible Successor exists in the topology table? → It enters Active state and sends QUERY messages to all neighbors
6. What is a key advantage of using VXLAN over traditional VLANs in large data centers? → Support for up to 16 million segments vs 4,096 VLANs
7. Which header field uniquely identifies a VXLAN segment and is carried in the VXLAN header? → VNI (VXLAN Network Identifier)
8. Which Cisco SD-WAN component acts as the orchestrator and facilitates initial authentication of WAN Edge routers? → vBond
9. What is produced once labels are exchanged over LDP between two routers? → LFIB
10. Removes one character0 → Ctrl-D
11. In the Cisco SD-Access architecture, what technology is used to offer Layer 2 and Layer 3 logical networks? → overlay network
12. What is the function of IP SLA in Cisco IOS? → Proactively measure network performance metrics like latency, jitter, and packet loss
13. What control plane protocol is employed between vSmart controllers and Cisco SD-WAN routers? → OMP
14. What is the function of a Cisco DNA Center intent-based networking API? → Express the desired network state and let the platform determine how to implement it
15. What is the primary function of MACsec (IEEE 802.1AE)? → Encrypt and integrity-protect traffic at Layer 2 on a hop-by-hop basis
16. Which QoS model provides per-flow resource reservation using RSVP signaling? → IntServ
17. What type of ACL can filter traffic based on both source and destination IP, and also TCP/UDP port numbers? → Extended ACL
18. Which feature builds upon DHCP Snooping to prevent hosts from sending traffic with a spoofed source IP? → IP Source Guard
19. What job does a fabric edge node have in an SD-Access setup? → Connects endpoints to the fabric and forwards their traffic.
20. Which Cisco IOS feature can detect and block rogue DHCP servers on a LAN segment? → DHCP Snooping
21. What number of bits make up an MPLS label? → 20
22. Which component in an NFV architecture is responsible for lifecycle management of VNFs? → VNFM
23. What is the purpose of Dynamic ARP Inspection (DAI)? → Prevent ARP spoofing by validating ARP packets against the DHCP snooping binding table
24. Which levels of logging are turned on by default? → 0 - 7
25. This progresses 1 word. → Esc-F
26. What is the default BGP hold time negotiated between Cisco routers? → 180 seconds
27. What distinguishes the FIB and LFIB from one another? → FIB forwards IP packets while LFIB forwarded *labelled* IP packets.
28. Neighbor Finding Setting up the session Label Exchange and Distribution Which three are these? → LDP's three steps
29. Which NTP stratum level indicates the NTP server is directly connected to an authoritative time source? → Stratum 1
30. Where is radio resource management carried out in a wireless Cisco SD-Access solution? → control plane node