Network Topologies (Star, Mesh, Ring): Designing physical and logical paths of network nodes, assessing failure tolerance, and mapping redundant physical links.
The OSI Model (7-Layer Deep Dive): Analyzing modern communications through a standardized conceptual framework, tracing data encapsulation from application down to physical media.
The TCP/IP Model (4-Layer DoD Architecture): Interacting with the practical, protocol-driven four-layer model that guides data transmission across local and global networks.
Layer 2 Switching (MAC, Ethernet, ARP): Managing local physical connections, processing Ethernet frames using hardware MAC addresses, and resolving logical IP addresses to physical MAC addresses via Address Resolution Protocol (ARP).
Layer 3 Routing (IPv4, Public vs. Private, NAT): Directing traffic across logical network boundaries using logical IP addressing, partitioning subnets via standard RFC 1918 allocations, and translating IP headers using Network Address Translation (NAT).
Subnetting & CIDR Math: Calculating logical network boundaries, defining subnet sizes, and managing Classless Inter-Domain Routing (CIDR) ranges using binary logic and network masks.
Routing Protocols (OSPF, EIGRP, BGP, ASNs): Discovering and maintaining paths across networks using Interior Gateway Protocols (link-state vs. distance-vector) and routing global internet traffic via Border Gateway Protocol (BGP) across Autonomous System Numbers (ASNs).
Layer 4 Protocols (TCP vs. UDP): Managing end-to-end transport mechanics, negotiating reliable sessions using the TCP 3-Way Handshake, handling flow control via windowing, and processing stateless UDP datagrams.
Network Ports & Sockets: Managing ephemeral and reserved logical ports to allow applications and services to bind to and listen on physical network interfaces.
DNS Architecture (TLDs, Zones, DNSSEC): Resolving domain names to logical IP addresses through hierarchical servers (root, TLD, authoritative), configuring zone records (A, MX, TXT), and securing queries with cryptographic DNSSEC signatures.
DHCP (The DORA Process): Automating dynamic IP address allocation across local networks using the Discover, Offer, Request, and Acknowledge (DORA) lease process.
HTTP/HTTPS (Headers, Methods, QUIC): Interacting with web applications, processing request/response headers and verbs (GET, POST), and migrating to high-performance transport protocols (HTTP/2 and UDP-based HTTP/3/QUIC).
Remote Management Protocols (FTP/SFTP, SSH, RDP): Establishing secure and legacy remote administration channels, using asymmetric key pairs for console access (SSH), and transmitting graphical desktop sessions (RDP).
Advanced Layer 2 (VLANs, Trunking, STP, BPDU): Partitioning physical switches into logical broadcast domains (802.1Q), running multi-VLAN trunk lines, and preventing network loops using Spanning Tree Protocol (STP).
IPv6 (Addressing, SLAAC, Neighbor Discovery): Transitioning to next-generation hexadecimal IP addressing, auto-configuring client interfaces without DHCP (SLAAC), and discovering adjacent nodes without broadcast ARP.
Wireless Networking (802.11, WPA2/WPA3, RADIUS): Securing over-the-air communication, examining physical frequencies, implementing corporate network access, and verifying credentials via EAP over RADIUS servers.