If you cannot connect to the internet, it does not matter how powerful your computer is or how much software you have installed. Network hardware is the physical equipment that makes connectivity possible, and the CompTIA Tech+ exam expects you to know the role of each piece. For someone studying for FC0-U71, understanding these devices is the difference between guessing which cable to plug in and confidently building a small office network.
Jump to a section
A simple way to picture Network Hardware and Connectivity
50 pieces of a 500-piece jigsaw puzzle arrive in one box. 50 more come in a second box, 50 in a third, and so on. Each box represents a data packet, a small chunk of a larger message sent across a network. The puzzle board is your computer, the final image is a webpage or email. The puzzle pieces travel from the manufacturer (a server) to your door via a delivery truck (a network cable or Wi-Fi signal). But here is the catch: the pieces from different boxes might arrive out of order, some might be dropped, and the truck might take different routes each time. The network interface card (NIC) inside your computer acts as the puzzle solver. It reassembles the pieces in the correct order, checks for missing pieces, and requests replacements if any piece is lost. The router is like your local postal sorting office. It looks at the address on each puzzle box and decides which delivery truck should carry it next. The switch is like a handler in a warehouse who sorts boxes going to the same neighbourhood into one pile, ensuring they reach the correct room in your house. An access point is the wireless doorbell that lets the delivery person hand off boxes through the air, without a wire. This whole process happens in milliseconds for billions of daily puzzles, making the internet feel seamless.
If one piece is missing or damaged, the entire puzzle seems incomplete. That is packet loss. If trucks arrive too slowly, you experience network latency. If multiple deliveries clog your driveway, that is network congestion. Every jump between sorting offices is a network hop, and the number of hops increases response time. Tools like ping send a tiny 'test piece' to the manufacturer and measure how long the round trip takes. Understanding this jigsaw process is the core of network hardware: each device has a specific job in moving, sorting, and reassembling digital puzzles so that your computer shows a complete picture.
Network hardware is the physical equipment used to connect computers and other devices so they can share data. The most basic piece is the network interface card (NIC). Every computer, laptop, tablet, and smartphone has one. A NIC is a hardware component, often built into the motherboard, that gives the device the ability to connect to a network. It has a unique address called a MAC address (Media Access Control), which is like a serial number burned into the card at the factory. This MAC address is how devices identify each other on a local network.
The most common type of NIC today uses Ethernet for wired connections or Wi-Fi for wireless. Ethernet NICs have an RJ45 port, which looks like a wide telephone jack, and they connect using twisted-pair copper cables (Cat5e, Cat6). Fibre optic NICs use a different connector (LC or SC) and carry light signals instead of electrical ones, allowing much faster speeds over longer distances. Every NIC has a speed rating, such as 100 Mbps (megabits per second), 1 Gbps (gigabit), or 10 Gbps.
Once a device has a NIC, it needs a way to connect to the broader network. That is where the switch comes in. A switch is a central device that connects multiple devices on the same local network. When your computer sends data to a printer, the switch reads the destination MAC address from the data packet and forwards it only to the port where the printer is connected. This makes switches much more efficient than older hubs, which would broadcast the data to every port. Switches operate at Layer 2 of the OSI model (the data link layer), meaning they work with MAC addresses. Managed switches allow an IT administrator to configure settings like VLANs (virtual LANs) and port security, while unmanaged switches simply plug and play.
If you want to connect your local network to the internet, you need a router. A router connects two or more different networks together. It reads the IP address (Internet Protocol address) in each data packet and decides the best path to send it toward its destination. Routers operate at Layer 3 (the network layer) and use routing tables to make forwarding decisions. In a home network, the router also performs Network Address Translation (NAT), which allows multiple devices to share a single public IP address. Many home routers combine a router, a switch, and an access point into one box, but on the exam you must distinguish the separate functions: it is the router that routes between networks, the switch that connects local devices, and the access point that provides wireless connectivity.
An access point (AP) is a device that allows wireless devices to connect to a wired network using Wi-Fi. It is not the same as a router. A standalone access point connects to a switch or router via an Ethernet cable and then broadcasts a Wi-Fi signal. In large offices or schools, multiple access points are placed around the building to cover the area with a seamless Wi-Fi signal. Access points manage wireless security protocols like WPA3 (Wi-Fi Protected Access 3) and handle client authentication.
A modem (modulator-demodulator) converts digital signals from your computer into analogue signals that can travel over telephone lines, cable TV lines, or fibre optic cables, and vice versa. The modem connects your local network to your internet service provider (ISP). In the exam, remember that a modem connects to the ISP, a router connects networks, an access point connects wireless devices, and a switch connects wired devices.
Other common hardware includes:
A wireless range extender or repeater: receives an existing Wi-Fi signal and rebroadcasts it to extend coverage. It often cuts bandwidth in half because it uses the same radio to receive and retransmit.
A firewall: a device or software that monitors and controls incoming and outgoing network traffic based on security rules. Hardware firewalls are often built into routers, but a dedicated firewall appliance provides more granular control.
A patch panel: a passive panel of ports that sits in a server room, used to organise incoming Ethernet cables from wall jacks. Cables from the patch panel are then connected to the switch using short patch cables.
Power over Ethernet (PoE) injector: a device that sends electrical power along with data over an Ethernet cable, allowing devices like security cameras or access points to receive power without a separate electrical outlet.
Understanding the purpose of each device is critical for the Tech+ exam. You will also need to know common cable types: Ethernet (Cat5e, Cat6), coaxial (used for cable TV and internet), and fibre optic (used for high-speed, long-distance connections). Each has different speed and distance capabilities. For example, Cat5e supports up to 1 Gbps at 100 metres, while fibre can go 10+ kilometres at 40 Gbps or more.
1. Identify the Need
Determine how many devices need to connect, whether they are wired or wireless, and whether internet access is required. This dictates what hardware is needed. For example, if you have ten wired computers and already have internet from an ISP, you need a switch to connect them, not a router.
2. Select Appropriate Cabling
Choose the right cable type based on distance and speed. For distances up to 100 metres and gigabit speeds, Cat5e or Cat6 Ethernet is appropriate. For longer distances or higher speeds, fibre optic cable is needed. Consider environmental factors like interference and whether the cable will run in walls (plenum-rated cable may be required).
3. Connect the Modem to the Router
The modem (from the ISP) must connect to the router's WAN (wide area network) port using an Ethernet cable. This establishes the internet connection. Without this step, devices on the local network cannot reach the internet, even if they can communicate locally.
4. Connect the Router to the Switch
Run an Ethernet cable from one of the router's LAN ports to any port on the switch (usually the first port or a designated uplink port). This allows the switch to distribute the internet connection to all wired devices plugged into it. The switch automatically learns where each device is located via MAC addresses.
5. Add Wireless Coverage with Access Points
If wireless connectivity is required, connect an access point to the switch via Ethernet. Use Power over Ethernet (PoE) if possible to avoid needing a separate power outlet near the access point. Configure the access point with the same SSID and security settings (like WPA3) as the router's wireless network, or use a dedicated wireless controller for seamless roaming.
6. Verify Connectivity and Performance
Use tools like ping, traceroute, and network speed tests to ensure data flows correctly. Check that wired devices receive IP addresses via DHCP from the router and that wireless clients can associate with the access point. Cable testers can verify physical connectivity. Document IP addresses, device locations, and cable labels for future troubleshooting.
An IT technician arrives at a small law office that has been having slow internet and intermittent dropped connections. The office has ten desktop computers, one network printer, and a VoIP phone system. Currently, all computers plug directly into a single home-grade router that also acts as a switch and access point. The technician begins by inspecting the existing equipment.
First, the technician identifies the modem supplied by the ISP, a cable modem connected to the wall. The modem shows solid link lights, indicating a good connection from the ISP. The technician then looks at the router. It is a consumer model with four LAN ports and a built-in Wi-Fi radio. The technician explains that this all-in-one device is being overloaded: the router has to handle routing between the internet and the local network, switching between all ten computers, and also managing Wi-Fi for five smartphones. This causes high CPU utilisation on the router, leading to packet loss and latency.
The technician recommends separating the functions. The plan is:
Keep the existing modem (or upgrade to a business-grade modem).
Add a dedicated router (a small business router like a Ubiquiti EdgeRouter or MikroTik).
Add a 16-port managed switch to connect all ten desktop computers and the network printer via Ethernet.
Add a standalone business-class access point (like a Ubiquiti UniFi AP or a Ruckus AP) mounted on the ceiling for wireless coverage.
The technician walks through the installation: 1. Power down the old router. Unplug the Ethernet cable from the old router's WAN port and plug it into the new dedicated router's WAN port. 2. Connect the new router's LAN port to one port on the new switch using a short Cat6 patch cable. 3. Run Ethernet cables from each desktop computer's NIC to the switch ports. Use a cable tester to verify continuity on each run. 4. Configure the new router: set the WAN interface to DHCP to obtain an IP from the modem, enable NAT, configure a DHCP server for the LAN (192.168.1.0/24), set up a simple firewall rule to block inbound traffic from the internet. 5. Mount the access point on the ceiling in the centre of the office. Connect a PoE injector near the switch: plug the switch into the injector's data port, then a cable from the injector's data+power port to the access point. The access point now receives both data and power over the single Ethernet cable. 6. Configure the access point with the same SSID and WPA3 password on the router's management interface (or via a dedicated controller software). Enable band steering to push 5 GHz clients to the faster band. 7. On the managed switch, enable features like VLAN (optional), port security to prevent unauthorised devices from plugging in, and link aggregation if more bandwidth is needed between switch and router.
The result: the router now handles only routing (very little CPU load), the switch handles all local traffic at full wire speed (no CPU overhead), and the access point handles wireless clients without interference from switching tasks. Network speed tests show consistent 900 Mbps wired and 400 Mbps wireless, compared to the previous 50 Mbps wireless with frequent drops. The technician documents all settings, labels cables at both ends, and provides the office manager with a simple network diagram.
This scenario demonstrates that an IT professional must not only identify each piece of hardware but also understand how they work together and when to use dedicated devices versus all-in-one units.
The FC0-U71 exam objective 4.2 asks you to identify and explain the purpose of common networking hardware. Expect multiple-choice questions that test the difference between similar devices. The exam loves to present a scenario and ask which hardware would solve a specific problem.
Common topics tested:
Distinguishing between router, switch, hub, access point, and modem.
Understanding that a switch forwards data based on MAC addresses, while a router forwards based on IP addresses.
Knowing that a modem connects to the ISP and a router connects different networks.
Recognizing that a hub blindly replicates data to all ports (works at Layer 1) and is outdated, whereas a switch sends data only to the correct device.
Identifying cable types: Cat5e (up to 1 Gbps), Cat6 (up to 10 Gbps for short distances), coaxial (used for cable internet and TV), fibre optic (used for long distances and high speeds).
Understanding the role of a NIC and that each NIC has a unique MAC address.
Knowing that Power over Ethernet (PoE) allows a device to receive power through the Ethernet cable, eliminating the need for a separate power outlet.
Identifying that a wireless range extender can reduce bandwidth and increase latency.
The exam sets traps by presenting similar-sounding answers. For example: - 'Which device should you install to connect two different networks?' The answer is a router, not a switch, not a bridge. - 'What device connects a local network to the internet?' The answer is a modem (or a modem and router combo, but the question likely expects just the modem). - 'Which device reads MAC addresses to forward data?' The answer is a switch, not a router. - 'A user wants to add Wi-Fi to a wired network that already has a switch. What device is needed?' The answer is an access point, not a router. - 'Which network hardware operates at Layer 2 of the OSI model?' The answer is a switch. - 'Which network hardware operates at Layer 3?' The answer is a router.
You must also memorise the key ranges and distances:
Ethernet (Cat5e): 100 metres max, 1 Gbps.
Fibre optic: depends on type (multimode up to 2 km, single mode up to 100+ km).
Wi-Fi: typically 30-50 metres indoors, less with obstacles.
Another trap: the exam may ask about 'a device that connects multiple devices and sends data to only the intended recipient.' This is a switch, not a hub. Hubs broadcast to every port.
Finally, know the purpose of a patch panel: organisation. Not for signal boosting or network security.
Make sure you understand that most home 'routers' are really three devices in one (router, switch, access point) and that the exam may ask about the function of the 'access point' part separately. For example, a question might describe a scenario where a user has a wired router but no wireless signal, and the solution is to add an access point. The exam expects you to know that adding another router would cause double NAT issues, whereas an access point is the correct addition.
A network interface card (NIC) is the hardware inside a device that provides connectivity, and every NIC has a unique MAC address burned into it at the factory.
A switch connects devices within the same local network and forwards data only to the intended device based on its MAC address, making it more efficient than a hub.
A router connects two or more different networks, such as your home network and the internet, and makes forwarding decisions based on IP addresses.
A modem converts digital signals from your network into analogue signals for transmission over telephone, cable, or fibre lines, and vice versa.
An access point adds wireless connectivity to a wired network, but it does not route traffic or provide internet on its own.
Power over Ethernet (PoE) allows a single Ethernet cable to carry both data and electrical power, eliminating the need for separate power outlets for devices like security cameras and access points.
A hub repeats incoming data to every port, making it a security and performance risk, and is considered obsolete in modern networking.
Common Ethernet cable categories include Cat5e (up to 1 Gbps, 100 metres), Cat6 (up to 10 Gbps at shorter distances), and Cat6a (up to 10 Gbps at 100 metres).
These come up on the exam all the time. Here's how to tell them apart.
Switch
Forwards data based on MAC address to the specific device
Operates at Layer 2 (data link layer) of the OSI model
More secure because data only reaches the intended recipient
Hub
Repeats data to every connected device regardless of destination
Operates at Layer 1 (physical layer) of the OSI model
Less secure because all devices see all traffic
Router
Connects two or more different networks (e.g., home to internet)
Uses IP addresses to make forwarding decisions
Operates at Layer 3 (network layer) of the OSI model
Switch
Connects devices within the same local network
Uses MAC addresses to make forwarding decisions
Operates at Layer 2 (data link layer) of the OSI model
Modem
Converts signals between ISP medium and digital network
Has one WAN port (to ISP) and one LAN port (to router)
Does not assign IP addresses or perform NAT
Router
Routes data between your local network and other networks
Has one WAN port (to modem) and multiple LAN ports
Performs NAT and DHCP (assigns IP addresses to local devices)
Access Point (AP)
Provides only wireless connectivity to a wired network
Does not perform routing or DHCP
Must be connected to a router or switch to function
Router (Wireless)
Combines routing, switching, and wireless functions in one device
Performs routing and DHCP
Can function standalone without a separate router
Ethernet Cable (Cat5e)
Uses copper wires to carry electrical signals
Maximum distance of 100 metres before signal degrades
Susceptible to electromagnetic interference
Fibre Optic Cable
Uses glass or plastic fibres to carry light signals
Can transmit over kilometres without signal loss
Immune to electromagnetic interference
Mistake
A router and a modem are the same thing.
Correct
A modem connects your network to your ISP and converts signals. A router connects multiple networks together and manages traffic between them. Many home devices combine both, but they are distinct functions.
Because most home internet devices are combination units that look like a single box, people assume they are one device. Manufacturers market them as 'routers' but they contain both a modem and a router (and often a switch and access point).
Mistake
Wi-Fi and the internet are the same thing.
Correct
Wi-Fi is a wireless local network technology that connects devices to each other and to a router. The internet is the global network of networks. You can have Wi-Fi without internet (e.g., connecting two laptops to share files) and you can have internet without Wi-Fi (e.g., using a wired Ethernet connection).
Most people access the internet through Wi-Fi at home, so they equate the two. When Wi-Fi is down but internet is still working (if you plug in a cable), the confusion becomes clear.
Mistake
A switch and a router do the same job.
Correct
A switch connects devices within the same local network and uses MAC addresses. A router connects different networks (e.g., your home network to the internet) and uses IP addresses. A router often includes switch functionality, but the Layer 2 vs Layer 3 distinction is crucial.
In small office and home devices, these functions are built into one box, so beginners think they are interchangeable. Understanding the OSI model layers helps separate them.
Mistake
A network switch provides internet to connected devices.
Correct
A switch connects devices to each other locally but does not provide internet by itself. The switch must be connected to a router (which has a connection to a modem) to give devices internet access.
Plugging a computer into a switch with no router attached will allow the computer to talk to other devices on the switch (file sharing, printing) but not to the internet. This is a common discovery error.
Mistake
A higher Cat number (e.g., Cat8) is always better for any network.
Correct
Higher Cat cables support higher speeds and frequencies but have shorter maximum distances and often require more shielding. For a typical home or small office network, Cat5e or Cat6 is sufficient. Cat6a or Cat8 is only needed for specific high-speed data centre environments.
Marketing pushes 'faster is better' and people buy Cat8 cables for home networks, not realising there is no benefit over Cat6 for gigabit internet speeds, and they cost much more.
Mistake
Turning off Wi-Fi on a router stops all network access.
Correct
If you turn off Wi-Fi, only wireless devices lose connectivity. Wired devices connected via Ethernet to the router or a switch will still have network access. The router still performs its routing and DHCP functions for wired clients.
People associate the router with the wireless signal because they see the blinking lights and antenna, forgetting that the wired ports provide independent connectivity.
Reveal each answer, then mark whether you got it right. Score 60%+ to unlock the next chapter.
No. You can connect two computers directly with an Ethernet crossover cable (or a standard cable if both NICs support Auto MDI-X) and configure static IP addresses. Alternatively, you can use a switch without a router to connect multiple computers for local file sharing.
A switch connects devices on the same local network and moves data between them using MAC addresses. A router connects two different networks (like your home network and the internet) and moves data between them using IP addresses. Think of a switch as an internal organiser and a router as the gateway to the outside world.
Yes. Fibre optic internet still requires a modem (often called an ONT or Optical Network Terminal) to convert the light signals from the fibre into electrical signals that your router can use. The ONT serves the same function as a cable or DSL modem.
Yes, most home routers can be configured to operate in access point mode. You disable the DHCP server and connect a LAN port (not the WAN port) to your main network. This effectively turns the router into a switch and access point combined. However, a dedicated access point is simpler and often more reliable.
A patch panel is a passive device with multiple RJ45 ports mounted in a server rack. Cables from wall jacks around the building terminate at the back of the patch panel. Short patch cables then connect the front ports to the switch. It keeps the wiring organised, makes changes easy, and protects the switch ports from wear.
Not necessarily. Standard Cat5e or Cat6 Ethernet cables can carry PoE as long as the cable length does not exceed 100 metres and the cable quality is adequate. The PoE injector or PoE switch provides the power through the same cable. However, for outdoor or high-power PoE devices (like pan-tilt-zoom cameras), you may need thicker gauge or outdoor-rated cable.
A network hop is each intermediate device (usually a router) that data passes through on its journey from source to destination. Every hop adds a small amount of delay (latency). The traceroute command shows each hop and the time it takes to reach it.
You've finished Network Hardware and Connectivity. Continue through the FC0-U71 study guide to build a complete picture of the exam.
Done with this chapter?