The Ultimate Network Security Training Course: All In One

Examine the open systems interconnection model and its seven-layer network stack—an abstract framework designed to support current and future networks, with each layer only communicating with adjacent layers.

Explore the seven-layer OSI model as an abstract framework for network communication from physical to application. Understand layer order and how routers use layer three to forward data.

explains how the application layer initiates network communication, performs DNS name resolution to IP addresses, and uses gateway functions to translate protocols across layers.

Understand the presentation layer, layer six of the OCI model, which converts data from applications into a standard format compatible with all network protocols, where encryption and compression should occur.

Understand the session layer of the OSA model, which manages communications with remote endpoints, enables dialog control and checkpoint-based error recovery, and supports simplex, half duplex, and full duplex modes.

Explore how the transport layer segments a data stream into one kilobyte payloads, adds headers, and uses tcp or udp with port numbers to manage end-to-end transfer.

Examine how the TCP header encodes ports, sequence and acknowledgment numbers, and six flags to ensure reliable, ordered delivery. Compare this with UDP's connectionless, best-effort delivery with no handshakes.

Master transport layer concepts by comparing tcp and udp, and see how source and destination ports (0–65535) identify server services, registered ports (1024–49151), and ephemeral client ports (49152–65535).

Compare tcp and udp choices and map well-known port numbers to services, from ftp and ssh to http and ipsec, while noting clear-text vulnerabilities and the need for encrypted channels.

Explore the network layer, covering IP addressing, routing decisions, fragmentation and reassembly, DNS lookups, NAT, ICMP, MPLS, RIP, OSPF, and BGP, plus routers and the packet-filtering firewall.

Explore the IPv4 header, including version, protocol number, and source/destination addresses. Understand how the IP address, subnet mask, default gateway, and DNS enable routing and name resolution with CIDR notation.

Explore IPv4 addressing at the network layer, defining network, host, and broadcast addresses via the and operation on an IP address and subnet mask, noting these addresses cannot be assigned.

Explore IPv4 addressing by class a–e ranges, private addresses 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, and APIPA 169.254, plus NAT and loopback 127.0.0.1.

Explore IPv6 addressing, a 128-bit space written in hexadecimal with abbreviated forms. Discover built-in QoS, IPsec encryption, auto-configuration via router advertisements, and tunneling or translation with IPv4 networks.

Explore IPv6 addressing and the network layer, including global unicast, unique local, link-local, multicast, and 128-bit addresses; and learn how regional internet registries, DNS, and DHCPv6 support connectivity.

The lecture explains how a host uses source and destination IPs, DNS, and subnet mask to decide local versus remote delivery, then forwards via arp to the default gateway.

Explore the data link layer, including LLC and MAC, MAC addresses, and media access methods such as polling, token passing, and carrier sense multiple access to prevent collisions.

Explore the data link layer, where frames carry source and destination MAC addresses, ARP resolves MACs, CRC ensures integrity, and bridges, switches, and wireless access points forward traffic.

Explain the 48-bit MAC address hardcoded into a network interface, how ARP maps IPs to MACs on the local subnet, and hand frames to the default gateway.

Explore how the address resolution protocol maps IP addresses to MACs and how ARP cache poisoning creates a man-in-the-middle by spoofing mappings, and review CRC-based error detection.

Explore the physical layer’s role in encoding binary bits into media and its lack of intelligence. See how OSI and TCP/IP models map frames, packets, and datagrams.

Explore transmission media and technology by defining media, attenuation, interference, including emi and rfi, and how impedance mismatches and connectors affect signal integrity.

Explain emanations from electron-based signaling on copper and wireless media, show how crosstalk causes attenuation and interference, and contrast baseband with broadband and fiber optics using wavelength division multiplexing.

Rank media from most to least secure, noting attenuation, crosstalk, interference, and emanations, and explain fiber optic cables using photons for higher data rates as the backbone choice.

Explore coaxial cable fundamentals, including center copper conductor and grounded shielding that reduce emanations, baseband and broadband signaling, plus bus topology terminators and twisted pair ethernet with RJ-45.

Explore Ethernet twisted pair cabling, from category one through category six and gigabit implementations, including crossover cables and plenum safety with floral polymer jackets and cost considerations.

Explore wireless networking fundamentals, including IEEE 802.11 standards, radio frequency transmissions, and access point architecture, while examining security challenges and high-throughput MIMO OFDM for 802.11n/ac.

Explore modulation and encoding techniques, including digital signaling with unipolar and bipolar schemes, and analog RF methods like amplitude modulation, frequency modulation, phase shift keying, and quadrature amplitude modulation.

Explore modulation and encoding fundamentals, including frequency, wavelength, amplitude, fm, and the distinction between synchronous and asynchronous transmissions with start and stop bits for binary data.

Explore time division multiplexing on baseband wires and how sliced time shares boost bandwidth, then compare with frequency division multiplexing on coax and wavelength division multiplexing on fiber optics.

Explore network topologies from bus and ring to star, mesh, and tree, with focus on single points of failure, redundancy, and the distinction between physical and logical topology.

Explore intranets, extranets, and the internet, and how private networks behind firewalls form trusted environments. Compare branch-connected extranets to the public internet, the least secure zone.

Trace the spectrum of network sizes from personal area networks with Bluetooth and Zigbee to global area networks like the internet.

Explore unicast, broadcast, multicast, and anycast transmission types, detailing unicast 1-to-1 delivery, layer 2 and layer 3 broadcasts, Class D multicast with IGMP, and anycast for nearest service discovery.

Learn how circuit switching in the telco, or POTS, creates a dedicated path for a telephone call, delivering data in FIFO order with consistent latency for time-sensitive audio and video.

Explore how packet switching networks route data across a cloud of routers and switches, compare with circuit switching, and learn routing, load balancing, and quality of service for bursty traffic.

Explore how layer two handles media access with polling, token passing, and contention methods, showing how collision avoidance and collision detection prevent collisions on ethernet networks.

Discover token passing, including token bus and token ring, with a token master and active monitor maintaining a single token; explore fault-tolerant CDI and FTD networks across copper and fiber.

Explore carrier sense multiple access flavors, CSMA/CA and CSMA/CD, and how collision avoidance, announcement frames, and acks govern half-duplex wireless, early Ethernet, and AppleTalk networks.

Explore how CSMA/CD enables collision detection in full and half duplex networks, compare Ethernet and 802.11n/802.11ac with MIMO, and see how switches eliminate collisions for efficiency.

Explore how clients, application servers, and data repositories form a multi-layered network infrastructure. See how web applications traverse the presentation layer and DMZ to access data and run Java applets.

Discover how the middleware layer connects applications to diverse data repositories, transforming and preparing data—from XML and SAML to service oriented architecture and CORBA, COM/DCOM—for seamless client access.

Explore mainframe computers and dumb terminals, including screen scrapers that adapt data for new workstations. Understand security risks from unscheduled reboots and initial program load and the early SDLC/HDLC protocols.

Explore endpoint protection across desktops, BYOD, thin clients, and remote workers, and implement least privilege, antivirus, patching, monitoring, and physical security.

Explore infrastructure services powering a corporate network, including file and printer sharing, email, application services, and directory services with DNS, DHCP, domain controllers, VPN, and storage area networks.

Explore how remote administration enables secure, centralized access for administrators with strong authentication and auditing, using tools like remote desktop protocol and desktop sharing for helpdesk support.

Explore how physical segments and ip subnets form logical networks, and how routers, hubs, and bridges define collision and broadcast domain separation. Bridges use mac address tables and store-and-forward.

Define nodes, segments, and subnets, and explain collision and broadcast domains on a physical segment. Describe sockets as an IP address plus port number that selects a service.

Describe physical layer devices, from NICs and concentrators to media, repeaters, amplifiers, and hubs, noting that layer 1 handles only binary bits while MAC addresses enable layer 2 filtering.

Explore layer two data link devices that use MAC addresses to forward frames and reduce collision domains. Bridges memorize source MACs and broadcast to all ports, evolving into switches.

Explore bridging and layer 2 forwarding, where MAC address learning enables a switch to divide a segment into collision domains and forward frames efficiently, with VLANs and protocol snooping.

Discover how layer two devices and VLANs use port isolation to segment traffic, with switches and wireless access points handling logical segmentation.

Learn how layer three devices, especially routers, forward IP packets across subnets. Discover access control lists, default deny rules, route tables, and basic static to dynamic routing concepts.

Explore dynamic routing protocols, comparing distance vector and link state, with rip, eigrp, ospf, and bgp, and learn loop prevention using ttl, poison reverse, split horizon, and hold down timer.

Trace the evolution of firewalls from the packet filtering firewall to the next generation, and learn how screening routers, default deny ACLs, and port forwarding secure DMZ and internal networks.

Explore how a second-generation proxy firewall authenticates clients, applies security groups, and proxies requests to the internet, while application-layer proxies perform deep packet inspection to reassemble and inspect content.

Explore how a third generation stateful firewall uses a state table to permit outbound requests and deny unsolicited inbound traffic, and how dynamic packet filtering enables port openings.

Secure your firewall by changing the administrator password, enforcing a default deny, and implementing documented allow rules; enable remote logging and a whitelist within a layered security zone architecture.

Explore the dynamic host configuration protocol (dhcp) for automatic ip address allocation, the four-step handshake, ip uniqueness checks, and the risks of rogue dhcp servers and ip depletion attacks.

Explore how name resolution translates human-friendly names into IP addresses using sockets-based DNS, the resolver cache, and the hosts file, tracing NetBIOS and the shift to modern DNS.

Explore the domain name system, a name resolution service that maps fully qualified domain names to ip addresses like a book, enabling forward and reverse lookups.

Understand the domain name system architecture, including forwarders, root servers, and iterative queries. Explore TTL caching and split DNS for private and public namespaces in Active Directory environments.

Explore how DNS resolution works from root servers to servers, including root hints and TTL, and learn attacks like DNS poisoning and domain hijacking, plus DNS SEQ with X.509 certificates.

Explore authentication in networking infrastructure, covering Kerberos KDC within Active Directory, domain controllers, and remote access evolution from Radius and TACACS+ to Diameter and Extensible Authentication Protocol.

Analyze the storage area network (SAN) as a high-speed, highly available data repository with Fibre Channel over Ethernet or iSCSI, weighing private SAN versus cloud SAN security and backup considerations.

Explore software defined networks and separate the logical decision making plane from the packet handling plane. Apply a centralized policy across routers, switches, and access points using open flow.

Learn how network access control validates device health before granting corporate data access, using domain authentication, updates, antivirus, firewall, hips, vulnerability scans, remediation segments, and PKI certificates via 802.1X.

Explore wireless networking, from Bluetooth and wifi local area networks to 802.11n and 802.11ac, with emphasis on strong authentication and encrypting 100 percent of wireless communications.

Discover how IEEE 802.11 family evolved wireless networks from 2 Mbps at 2.4 GHz with WEP to 802.11i security, WPA/WPA2, and high-throughput MIMO and 802.11ac in the 5–6 GHz bands.

Understand how wireless cells form infrastructure networks via access points or ad hoc peer groups, with bridging and 802.1X authentication in enterprise settings.

Learn how wireless association occurs through the access point, beacon broadcasts, and ssid. Trace the evolution from wep to wpa and wpa2, and why wep should be disabled.

Explore 802.11i wireless security from WPA to WPA2, including TKIP, AES, key rotation, and CBC-MAC, and learn how EAP, 802.1X, Radius, and VPN secure access.

Change default wireless credentials and disable or conceal the ssid, then implement WPA with enterprise authentication and multi-factor authentication, while isolating wireless from the wired network using firewalls.

Explore MIMO evolution from 802.11n to 802.11ac, using up to eight transmitters, receivers, and antennas to boost data rates via spatial diversity and beamforming.

Trace the evolution of cellular networks from 1g to 4g, compare gsm, edge, cdma, and mimo, and explain how signaling schemes and layer two choices affect data rates and reliability.

Explore how network protocols define endpoint communication, map to ports, and relate to the tcp/ip layers, dns, icmp, nat/pat, and routing protocols like rip and bgp.

Explore the internet group management protocol, enabling multicast from a source to many receivers for audio and video, with clients registering for a class d address and routers duplicating packets.

Explore how icmp enables network self-tuning, attackers exploit it, using ping and traceroute to send echo request and echo response, test connectivity, and map hops with ttl and dns lookups.

Explore how NAT and PAT extend IPv4 using RFC 1918 private spaces, enabling one-to-many sharing, port forwarding, and stateful 1-to-1 mappings behind external firewalls.

Examine telnet, ftp, tftp, and snmp protocols and their security risks, including clear text credentials and port usage, and learn how ssh and ftp over ssl mitigate these issues.

Explore how email travels from SMTP for sending on port 25 or 465 with SSL, to retrieval via POP3 and IMAP, and how mime and smime enable attachments and encryption.

Explore protocols, focusing on instant messaging and hypertext transfer protocol. Assess data exfiltration and malware risks from mobile code, and enforce strict corporate policies with training and monitoring.

Explain how https uses a trusted certificate to verify a web server and establish an encrypted channel via a symmetric session key exchanged with public keys, replacing ssl with tls.

Compare windows file and print sharing, dfs services and linux nfs and lpd, detailing ports 137–139, 445, 515, 111, 2049, and 389, and explain qos reduces jitter for time-sensitive packets.

Understand virtual private networks that encapsulate and encrypt data to create secure channels between known endpoints, examining ssh, ssl/tls, and pptp as vpn technologies and their protocols.

Explore IPsec, the vpn standard delivering authentication, confidentiality, and integrity across IPv4 and IPv6. Learn transport and tunnel modes, ah and esp, and how gateways enable host and subnet connections.

Explore how ipsec vpn negotiation uses the internet key exchange to establish inbound/outbound security associations for ah and esp, indexed by spi, with isakmp and oakley guiding diffie-hellman key exchanges.

Learn how IPsec VPN uses authentication header with HMAC for data integrity, and encapsulated security payload for encryption, including transport and tunnel modes with net traversal considerations.

Examine layer two tunneling protocol (l2tp) that encapsulates frames over a layer two network and lacks built-in confidentiality, often paired with ipsec over udp 1701 for encryption.

Examine the security risks of industrial control protocols, including scada and DNP3, their air-gapped origins, and internet exposure. Emphasize the need for strong authentication, encryption, and awareness of port numbers.

Explore network sizes from personal area to global area networks and their technologies, including Bluetooth and Zigbee, master-slave pico nets, and trends like infrared deprecation.

Learn how local area networks provide high-speed, multi-segment connectivity bounded by firewalls and governed by administrative policy, with ethernet or wireless technologies and VLAN-based layer-two isolation that segments switch ports.

Connect campuses into a metropolitan area network using fiber, wireless bridges, or VPN, and explore last-mile technologies like cable modems and DSL, plus FDI and SONET backbones.

Explore wide area networks, from SONET backbones and optical carrier units to T1/T3, E1/E3 links, ISDN, frame relay, ATM, MPLS, and satellites.

Explore integrated services digital network (isdn) and Exodus 25 56 kbps channels, pbx security risks, and frame relay evolution with committed information rate and permanent virtual circuits.

Explore asynchronous transfer mode and MPLS in wide area networks, comparing ATM's 53-byte cells, SVC and PVC, with QoS and cut-through routing, plus VoIP gateways and registration servers.

Explore voice over IP concepts, including RTP/RTCP, SIP versus H.323, and the security risks of integrating VoIP with networks, plus satellite links and link encryption to reduce latency and eavesdropping.

Explore opportunistic browsing attacks that target weak users, including viruses and worms, and understand how unskilled attackers, or script kiddies, use drive-by methods in a grazing, spray-and-pray approach.

Explore how targeted attacks unfold from passive recon to active reconnaissance, footprinting, and fingerprinting to identify vulnerabilities, escalate privileges, entrench with backdoors, cover tracks, and pivot to deeper network access.

Examine attack vectors from server-side breaches to client-side compromises and the role of security awareness training, and explore denial-of-service attacks like syn flood, ping of death, and smurfing.

Examine teardrop and land denial of service attacks, including fragmentation abuse and TCP/IP spoofing, then the rise of DDoS botnets coordinating zombie hosts via handlers to flood targets.

The advanced persistent threat is a highly sophisticated, targeted attacker who stealthily avoids detection while conducting passive recon, fingerprinting targets, and exfiltrating data through careful, repeated probes and exploits.

Examine attacker methods like eavesdropping, social engineering, emanations, and cell phone attacks, then analyze man-in-the-middle, hijacking, and poisoning techniques that compromise confidentiality, integrity, and availability of information.

Review the CISSP domain four on communications and network security, covering the OSA model, layer one through seven, UDP and DNS concepts, and network attacks.