Domain 2: Networking (23%) - Network Hardware Devices, SOHO Network Configuration, Internet Connection Types and Networking Tools

IPv4 private ranges

• Not internet-routable; used with NAT (Networkd Address Translation)

• 10.0.0.0 - 10.255.255.255 (Class A size)

• 172.16.0.0 - 172.31.255.255 (Class B size)

• 192.168.0.0 - 192.168.255.255 (Class C Size - Common for SOHO - Small Office / Home Office)

IPv4 public

Routable on internet, assigned by ISP (Internet Service Provider)

IPv6

• 128-bit addresses (e.g., FE80::5D18:0652:FEFD:8F52)

• DNS is crucial (addresses are long/complex)

• eliminates need for NAT (Network Address Translation)

• auto-configuration support

APIPA (169.254.x.x)

Automatic Private IP Addressing when DHCP fails

Static IP (Internet Protocol)

Manually configured, used for servers, printers, network devices

Dynamic IP

Automatically assigned by DHCP, used for client devices

Subnet Mask

• Defines network and host portions of IP address

• Common masks: 255.255.255.0 (/24) | 255.255.0.0 (/16) | 255.255.255.128 (/25)

• Determines which devices are on same local network

Default Gateway

• Router IP address that forwards traffic to other networks

• Required for internet access and inter-network communication

• Typically first or last usable IP in subnet (e.g., 192.168.1.1 or 192.168.1.254)

Routers

• Connect different networks (e.g., LAN to WAN/internet)

• Make forwarding decisions based on IP addresses (Layer 3)

• Provide NAT (Network Address Translation) for private to public IP conversion

• Include firewall capabilities in SOHO models

Switch: Un-managed switches

• Plug-and-play, no configuration options, lower cost

• No advance features (VLAN, QoS remote management)

Switch: Managed switches

• Advanced configuration & remote management

• VLAN (Virutal Local Area Network) support, port configuration, monitoring, QoS (Prioritize

Switches “Local Street Directors” - Layer 2

• Connect wired devices (computers, printers, servers) within a single LAN

• Forwarding traffic using MAC addresses

• High-speed (ASIC hardware), many ports

Quality of Service (QoS)

• A set of technologies used in networking to manage traffic, reduce latency, and ensure the performance of critical applications

• It works by prioritizing bandwidth for high-priority data (e.g., video conferencing) over less critical traffic during network congestion. Key components include classification, marking, and queuing, which manage packet loss, jitter, and delays

Access Points

• Provide wireless connectivity to wired network

• Can be standalone or controller-managed for enterprise deployments

• Support multiple SSIDs (Service Set Identifier) for network segmentation

• PoE-powered for flexible placement

Power over Ethernet (PoE)

• PoE standards: 802.3af (15.4W), 802.3at/PoE+ (25.5W), 802.3bt/PoE++ (up to 100W)

• PoE injector: Adds power to single Ethernet cable

• PoE switch: Provides power to multiple devices through Ethernet ports

• Powers access points, IP cameras, VoIP phones without separate power cables

Patch panel

Organizes and terminates network cables in wiring closet

NIC (Network Interface Card)

Connects computer to network (wired or wireless)

ONT (Optical Network Terminal)

Converts fiber optic signal to Ethernet

DSL (Digital Subscriber Line) modem

Converts phone line (copper) signal to Ethernet for internet access

Cable modem

Converts coaxial cable signal to Ethernet for internet access

Firewall

Dedicated security appliance for traffic filtering

Cable Installation Tools

• Crimper: Attaches RJ45 connectors to Ethernet cables by compressing metal contacts

• Cable stripper: Removes outer jacket from cables without damaging internal wires

• Punchdown tool: Terminates wires into patch panels, keystone jacks, 110 blocks

Cable Testing Tools

• Toner probe (tone generator and probe): Traces and identifies cables in walls, ceilings, cable bundles

• Wi-Fi analyzer: Scans wireless networks, identifies channel congestion, measures signal strength

• Cable tester results: Tests all 8 wires in Ethernet cable, identifies miswiring or broken connections

Common Cable Issues

• Improper termination: Four wire pairs not properly punched down causes connectivity issues

• 10/100 Mbps Ethernet: Uses only 2 pairs (4 wires), can work with partial wiring

• Gigabit Ethernet: Requires all 4 pairs (8 wires) properly terminated

Connection Technologies

• Fiber: Fastest (up to 10 Gbps+), most reliable, symmetric speeds, requires ONT

• Cable: Fast (up to 1 Gbps), shared bandwidth with neighbors, asymmetric speeds

• DSL (Digital Subscriber Line): Moderate speed (up to 100 Mbps), dedicated connection, speed decreases with distance

• Satellite: Available anywhere, high latency (500-700ms), weather-dependent

• Cellular (4G/5G): Mobile connectivity, variable speeds, data caps common

• WISP (Wireless ISP): Fixed wireless, line-of-sight required, rural areas

Network Types

• LAN (Local Area Network): Single building or campus, high speed, private ownership

• WAN (Wide Area Network): Connects LANs across large distances, internet is largest WAN

• PAN (Personal Area Network): Very small area, Bluetooth devices, typically 10m range

• MAN (Metropolitan Area Network): City-wide network, between LAN and WAN in size

• SAN (Storage Area Network): High-speed network for storage devices

• WLAN (Wireless LAN): Wireless version of LAN using Wi-Fi