Cisco U
Notes from the Cisco U CCNA learning path
2026
- STP varieties
- RSTP port roles and states
- PortFast and BPDU guard
- STP operation
- Redundant topologies and Layer 2 loops
- Issues in redundant topologies
- VLAN design considerations
- VLANs and access ports
- 802.1Q trunking
- Switch startup and verification
- VLSM: variable length subnet masking
- Verifying host IP settings
- Transport layer: TCP and UDP basics
- TCP vs UDP: reliable vs best effort
- Subnet increments and worked examples
- Reserved IPv4 addresses
- Public and private IPv4 addresses
- How HTTP works
- How DNS works
- How DHCP works
- Common ports and application protocols
- Subnetting: borrowing bits
- IPv4 address structure: network and host portions
- Unicast, broadcast, and multicast
- Subnet masks and the AND operation
- IP characteristics and binary conversion
- Half duplex, full duplex, and duplex configuration
- Frame switching and the MAC address table
- Switch benefits and characteristics
- Segments, collision domains, and switches
- LANs, WANs, and LAN components
- LAN components and functions
- Ethernet media: copper, fiber, and transceivers
- Ethernet frames, MAC addresses, and frame switching
- IOS CLI access, mode navigation
- Cisco IOS
- TCP/IP model layers
- Peer-to-peer communication and PDUs
- OSI to TCP/IP mapping and layer terminology
- OSI model, TCP/IP, and encapsulation
- Encapsulation and de-encapsulation
- Describing network traffic
- Network topologies and traffic characteristics
- Interpreting a network diagram
- Cisco CLI command reference