CompTIA Network+ N10-006

Explore the Open Systems Interconnection model and its seven OSI layers, and learn what each layer does. Discover how the layers interact to enable networking.

Explore the OSI model overview part 2, encapsulation, and network theory basics, including modulation techniques, numbering systems, broadband vs baseband, and CSMA/CA and CSMA/CD with carrier sense.

Compare the OSI seven-layer model with the four-layer model, noting they describe the same packet creation process from different design focuses. Some design elements fit neatly into one layer, while others straddle multiple layers.

Reference models divide the communication process into components, speeding design and development and aiding troubleshooting. They enable vendor interoperability and standardization across layers, and isolate changes to prevent cross-layer effects.

Explore the seven-layer osi model from application to physical, and how headers, ports, ip addresses, mac addresses, and checksums shape packets.

Discover how TCAP provides reliable delivery with acknowledgments and retransmission, orders packets with sequence numbers for in-order arrival, and manages flow control and a three-step session handshake to establish connections.

Explore how flow control uses receiver buffers and acknowledgments to prevent overload, with a dynamic window size that starts at one and adjusts to network conditions.

Routers route layer 3 traffic using routing tables, learning direct networks or dynamic routes, and split broadcast domains across interfaces to reduce broadcast traffic.

Explore data encapsulation and packet creation by adding headers at each layer from application to transport, internet, and network access, and reverse decapsulation at the destination.

Understand how multiplexing combines multiple conversations on a single physical medium and shares the medium through time division or frequency division techniques.

Explore the binary, hexadecimal, and octal numbering systems used in computers, including binary for IP addresses and packets, hex for IPv6 and MAC addresses, and octal for Unix permissions.

Understand the difference between baseband and broadband. Baseband uses a single channel that occupies the entire medium and employs time division multiplexing; broadband uses frequency division multiplexing to share bandwidth.

Define bit rate as data speed in bits per second and baud rate as symbol changes per second, when a modem uses voltage, frequency, or phase changes on a medium.

Learn how wavelength measures the distance between signal repetitions and the time between peaks, and how amplitude, the height above the median line, indicates signal strength.

Explore layer 1 physical layer concepts and media types, focusing on cables such as twisted pair, coax cables, and fiber cables.

Explore media types and connectors, and learn to install and terminate copper and fiber cables with the proper tools, while reviewing media converters and common copper issues.

Explore physical media cabling by examining coaxial, twisted pair, and fiber optic cables, noting coax's decline and the prominence of twisted pair in networks.

Coax cables feature copper center conductor, braided shield, and PVC; plenum rated variants prevent poisonous gas, with a 10base2 option using BNC connectors and a thicker version with vampire taps.

Discover twisted pair cables and how shielding reduces cross-talk, covering shielded and unshielded variants, 100-meter limits, and common RJ connectors from RJ11 to RJ45 at the network demarcation.

Explore fiber optic cabling that uses light, not electrical signals. Compare single-mode and multimode variants, noting distance and data trade-offs and immunity to EMI and RFI.

Learn how UTP and BNC couplers connect two cable runs as passive devices, understand attenuation limits on cable length, and why repeaters are needed to amplify signals beyond those limits.

Explore how broadband data travels over power lines using plug-in adapters and couplers, enabling communication between rooms via power outlets and twisted pair connections.

Explain serial connectors and serial communication, highlighting the db-9 and db-25 types and their male/female variants; desktops still use them, while usb largely replaces them.

Compare network cables by speed, attenuation distance, half duplex operation, noise susceptibility, and frequency to distinguish cable types and choose the right solution.

Explore ethernet wiring standards, including straight-through and crossover cables, their use with dissimilar versus similar devices, and the 568A/568B patterns, plus rolled and console cables and auto-sense.

This lecture explains a team one crossover cable used to connect to a team one connection, noting it crosses over pin types and pinning is not required for the exam.

Explore building wiring fundamentals, including main and intermediate distribution panels, IDFs on each floor, 110 block to patch panel connections, D-mark boundaries, and a smart jack.

Troubleshoot wiring by identifying short and open circuits, improper terminations, and mismatched standards, while addressing crosstalk, EMI/RFI, shielding, distance limits, and bad small form pluggable connectors.

Explore ethernet, the most widely deployed layer 2 protocol in local area networks. Learn how the data link layer operates and how mac addressing enables switches and layer 2 protocols.

Explore ethernet standards and wiring practices while examining the properties of ethernet and how it works, including gerson's multiple access as the contention method used in ethernet.

Understand how broadcast domains group devices on a segment and how routers limit broadcast traffic between networks. Learn how collision domains describe packet collisions and how switches break them up.

Explain carrier sense multiple access with collision detection on a shared bus network, detailing jam signals, random backoff, and how switches break collision domains to enable full duplex.

Half duplex ethernet sends or receives; full duplex transmits and receives simultaneously, doubling throughput. Hubs cannot do full duplex; switches and hosts set speed and duplex via auto negotiate.

Convert binary to decimal by examining bits that are on in an 8-bit pattern and adding their powers of two to obtain the decimal value.

Explore how four-bit binary values map to hexadecimal digits, converting values 0 through 15 into 0–9 and a–f.

Explore how mac addresses function as physical 48-bit hexadecimal identifiers on network cards, with a left 24-bit organizational identifier and a right 24-bit unique part, with vendors ensuring uniqueness, ipconfig /all.

Ethernet frames come in two types, one using a type field and the other a linked field, but both carry the source and destination MAC addresses after the preamble.

Explore IEEE Ethernet standards from 10base-t through 10gbase-sr, comparing copper and fiber cabling, speeds, and distance limitations to understand evolving network technologies.

Explore 802.3 standards for 10 gigabit ethernet over fiber, including single-mode fiber up to 10 km with extra wavelengths and long-wavelength lasers, and multimode fiber up to 300 m.

Explore IEEE 1901-2013, a standard for high-speed communication over electric power lines, and mobile high definition link for audio video connections between mobile devices and HDTVs.

Explore routers and switches as core network devices and examine a variety of other networking devices that perform essential functions to keep a network operating.

Explore network devices such as switches and routers, their functions, and roles, then examine common network services and applications, deployment requirements, and basic router and switch configuration.

Explore common network devices such as hubs, network cards, bridges, switches, routers, firewalls, and servers, plus less common devices you may encounter in real networks.

A hub acts as a simple junction with no intelligence, broadcasting to all ports and causing collisions that reduce throughput; switches eliminate collisions and dramatically speed up ghosting.

Explore network interface cards, the physical links to media via electrical, fiber, or radio methods, and how NICs connect through slots, motherboards, or built-ins, each with a unique MAC address.

Explore how a bridge learns MAC addresses and builds a MAC address table, forwarding frames only to the port with the destination address, while each port remains its collision domain.

Demonstrate how switches speed networks with hardware switching, build MAC address tables, and separate collision domains; compare routers operating at Layer 3 with IP-enabled interfaces versus switches without IPs.

Firewalls protect networks by blocking ports and inspecting traffic. A two-firewall setup with a DMZ demonstrates a layered security approach that requires bypassing both firewalls.

Explore host intrusion detection systems that monitor a single computer and network intrusion detection systems that inspect network traffic, plus analog modems and packet shapers that prioritize latency-sensitive traffic.

Explore how the dynamic host configuration protocol enables client–server IP address assignment using broadcast discovery, offer, request, and acknowledgment, and how DHCP relays extend this across subnets.

Explore specialized devices that combine routing and switching, filter traffic, balance loads across servers, resolve dns, proxy traffic, encrypt data, and terminate vpn connections.

Describe how a resolver uses the DNS hierarchy—from root to top-level to second-level domains—to resolve host names to IP addresses, including dynamic DNS with DHCP and A and MX records.

Explore how proxy servers sit between your network and the internet, funneling all information through the proxy. Compare reverse proxies and forwarding proxies, and how traffic flows to web servers.

Explore encryption devices, inline appliances that encrypt all data passing through to offload encryption from computers, and understand how content filtering examines transmissions for content violations.

A VPN concentrator is a hardware device that terminates multiple VPN connections, mapping them to a central point. It is called a concentrator for handling a high volume of connections.

Plan the network by keeping subnets small to reduce broadcast traffic and storms, deploy multicasting on switches, and separate collision and broadcast domains, while maintaining temperature and humidity.

Explore layer 3 routing and the IP protocol, and examine the TCAP IP protocol suite and how each sub protocol enables the networking operation.

Explore the ip protocol, its suite and rules, and examine how port numbers relate to various protocols within network communications.

Tcp/ip became the de facto standard after vendors used competing protocols; it underpins the internet with a four-layer model: application, host-to-host, internet, and network access.

Compare the DoD and OSI models, describing packet creation; map OSI's application, presentation, and session to the TCP/IP application layer, transport to transport, and datalink plus physical to network access.

Explore the TCP/IP protocol suite, detailing host-to-host and internet layer protocols like TCP, UDP, ICMP, and the application layer protocols such as Telnet, FTP, SMTP, HTTP, DNS, and DHCP.

Compare tcp and udp, detailing tcp's reliable, connection-oriented delivery with sequencing and acknowledgements versus udp's simple, best-effort, low-overhead delivery. Real-time apps favor udp to avoid delays from acknowledgments.

Explore port numbers and well-known ports, identify which protocols use tcp or udp, and learn how firewall rules use port numbers to block or allow traffic.

Learn how layer 3 encapsulates the IP header with source and destination addresses (not MAC addresses) and how port numbers are associated at this layer.

Use ICMP to test connectivity between systems; from a Windows computer, ICMP sends datagrams and awaits replies to confirm reachability.

Show how a host resolves an IP to a MAC address using the ARP cache, broadcasting on the local network to learn the MAC and place it in the packet.

Explore data encapsulation and de-encapsulation across the transport layer, internet layer, and data link layer, focusing on port numbers, IP addresses, and MAC addresses in headers.

See how data becomes protocol data units: data, segment, packet, and frame, and how routers route packets at layer 3 and switches switch frames at layer 2.

Explain how the transport layer assigns a random source port outside the first 1024 standardized numbers and uses the destination port to locate the service on the destination computer.

Explore how IP addresses identify each computer in Ethernet networks, how they relate to MAC addresses at Layer 2, and learn the basics of how IP addresses work.

The lecture introduces IP addressing, compares IPv4 and IPv6, explains public and private addressing, and defines network address translation.

Explain how IP addressing uses binary and 8-bit bytes to form IPv4 octets in a 32-bit address, and why network and broadcast addresses are reserved for routing and broadcasts (dhcp/arp).

Explore the hierarchical IP addressing scheme, a 32-bit structure divided into four octets. Identify dotted decimal, binary, and hexadecimal representations, with eight bits per field and nibble-level hex representation.

Understand classful IP addressing by identifying the network part and host part, and by using the first octet ranges for class A, B, C networks.

Understand private IP addressing and NAT to conserve public addresses, using class a/b/c private ranges and APIPA 169.254.x.x as a DHCP fallback.

Identify layer 2 and layer 3 broadcast concepts, include MAC addresses, differentiate unicast and multicast, and explain how multicast delivers packets from a source to many devices across networks.

Explore IP version 6, a 128-bit successor to IPv4, with eight colon-separated 16-bit sections, a global prefix, and global unicast, link-local, multicast addresses and 64 tunneling.

Routers advertise the network prefix to enable IPv6 auto configuration; hosts solicit with router solicitations and then build their IPv6 address using their MAC with the prefix in EUI-64 format.

Explain how link-local and global addresses relate, noting link-local addresses are auto-generated from the MAC, while global addresses are internet-public; include registry, subnet prefix, and 64-bit interface ID.

Explore transition mechanisms such as radio and open source radio, featuring relay servers, clients, and tunneling to carry IPv6 traffic across IPv4 networks.

Explain how DHCPv6 uses advertisements to determine IPv6 usage and assign an IPv6 address to the client. Show how these advertisements may also provide DNS server and gateway information.

Learn how routers break up broadcast domains by subnetting a classful network ID into smaller subnets, reducing broadcast traffic and improving subnet performance.

explore subnetting by dividing a classful network id into subnets, examine addressing and cidr, and discuss network address translation.

Reduce broadcast domains and traffic while simplifying troubleshooting with subnetting. Identify a class C network where the first three octets form the network part and last is the host part.

Borrow bits from the host portion to create subnets, using a formula to calculate the needed networks, and adjust the mask to 255.255.255.240 for at least ten subnets.

Determine the number of hosts per subnet using 2^n−2, where n is the host bits in the mask, accounting for network ID and broadcast address.

Learn to assign IP addresses and define network boundaries with a class C subnet mask, borrowing bits to form eight /24 networks, starting with 192.168.50.0 and the broadcast addresses.

Determine the block size or interval by counting total addresses per subnet, including network ID and broadcast, using one of three methods: formula, last-bit, or borrowing-bit approaches.

Learn about classless inter-domain routing notation as a compact slash notation for ip masks, where a slash followed by the bit count represents the mask used in networks.

Troubleshoot ip addresses by verifying loopback 127.0.0.1 to confirm network card and tcp/ip are functional, test local network ip, gateway, and cross-network ping, and check dns for name resolution.

Explore essential command line tools for network troubleshooting, including trace route and tracer, plus checking the ARP cache and ipconfig /all to verify IP and MAC mappings.

Learn how NAT converts private IPs to public IPs using a NAT router or server, including static, dynamic, and port address translation, or overload.

Explain how NAT translates an inside local IP to an inside global address, allowing many devices to share one IP using port numbers.

Explore routing concepts by examining how routers operate, how they use a routing table, and the functions and purpose of routing in a network.

Explore routing concepts and define essential terms to understand how routing operates. Examine different types of routing protocols and IP concepts, including high availability.

Routers determine the path to remote networks using the destination IP address and a routing table that includes neighboring routers and static and dynamic routes.

Examine how a host on one network reaches a host on another by using arp for the router’s mac, routing table lookups, and successive mac address changes at each hop.

Understand that routers discard packets without a routing table entry, then compare static and dynamic routing, and explore interior and exterior protocols like BGP and hybrid distance-vector, link-state IGPs.

Explore loopback interfaces as reliable, always-up router endpoints and how loopback addresses stay reachable when physical interfaces fail. Learn route redistribution and route aggregation to optimize routing tables.

A default route acts as a router's default gateway, forwarding packets to a next hop when the destination network is unknown in the routing table, such as 172.16.3.1.

Explore gateway redundancy using virtual routing redundancy protocol and hot standby routing protocol, sharing a virtual default gateway across two routers for seamless failover and uninterrupted traffic.

Explore how dynamic routing protocols populate the router's routing table, focusing on interior routing protocols and how these protocols work.

Build on routing basics by examining dynamic routing protocols, including OSPF, GOP, and RIP, to understand how these protocols enable route decisions.

Explore routing protocol basics by distinguishing static and dynamic routing, interior and exterior protocols, and the advanced distance-vector approach like RPE with distance vector and link-state traits.

Administrative distance selects the preferred routing source when multiple protocols advertise a network. Connected routes are 0, static routes are higher, and router favors lower distances like EIGRP over OSPF.

Compare distance-vector and link-state routing protocols, examining hop count, topology awareness, bandwidth, and delay to guide routing decisions. Examine GOP, a Cisco proprietary distance-vector variant with enhancements that resemble OSPF.

Understand distance vector routing protocols and how routers exchange full routing tables about directly connected networks to converge, revealing network id, exit interface, and hop count.

Explore the routing information protocol and its two versions, noting RIP v1's classful, broadcast-based, unauthenticated, and no discontiguous networks limitations, while RIP v2 adds authentication, discontiguous network support, and multicast.

Examine classful versus classless networks, showing fixed 28-bit masks waste on class C and how variable-length masks optimize address use, including point-to-point links, with classless protocols like OSPF.

A discontinuous network places subnets of the same classful network apart by a different classful network, so protocols like RIP v1 and OSPF require manual summarization.

Explore EIGRP and BGP, outlining neighbor, topology, and routing tables. Understand interior gateway protocols inside autonomous systems and how BGP links ASes across the internet.

Compare RIP version 2 with OSPF, noting bandwidth-based routing and faster convergence. Describe OSPF's area zero backbone and area border routers, and mention IS-IS as another area-based protocol.

RIPng and OSPFv3 adapt legacy routing protocols for IPv6, maintaining hop limit, loop prevention, and configuration fundamentals; differences center on IPv6 network IDs and addresses.