IT Cheat Sheets

Common TCP/UDP ports for Network+, Security+, and CCNA exams

The 7 layers of the OSI model with protocols, devices, and PDUs

IPv4 subnet masks, CIDR notation, and host calculations

Comprehensive comparison of IPv4 and IPv6 addressing

RIP, OSPF, EIGRP, BGP, and first-hop redundancy protocols

A, AAAA, CNAME, MX, TXT, and other DNS record types

Ethernet cables, fiber, coaxial, and T568A/B wiring standards

SC, LC, ST, MPO, and fiber polish types

Hubs, switches, routers, firewalls, and security appliances

RAID 0, 1, 5, 6, 10 with fault tolerance and capacity

802.11 wireless standards (a/b/g/n/ac/ax/be)

WEP, WPA, WPA2, WPA3, and 802.1X authentication

SSL/TLS versions, IPsec, SSH, and VPN protocols

Encryption algorithms, hashing, and key exchange

Cyber attacks, methods, and prevention techniques

Passwords, MFA, biometrics, and SSO protocols

NIST IR framework phases (PICERL)

IaaS, PaaS, SaaS, FaaS, and deployment models

Common HTTP response codes (1xx-5xx)

Essential Linux command line reference