1. Wireless
  2. Build a cable
  3. 66-block
  4. IGMP Snooping
  5. EIGRP
  6. MPLS
  7. VoIP
  8. OSPF
  9. Port security
  10. IPv6
  11. IPsec
  12. GRE
  13. T1
  14. QoS
  15. Virtualization
  16. rsyslog
  17. Web server
  18. PIM
  19. File sharing
  20. DHCP
  21. DNS
  22. AD
  23. Configuration Management
  24. SELinux
  25. LDAP
  26. GPO
  27. RADIUS and/or +
  28. TACAS
  29. HAProxy
  30. Firewall
  31. ACLs
  32. Trunking
  33. PXE Boot
  34. VLANs
  35. Tunneling
  36. RSTP
  37. Sitebook
  38. ELK Stack
  39. Link aggregation
  40. Load balancing
  41. Failover
  42. BGP
  43. RAID