Router vs Switch vs Access Point: What Each Network Device Actually Does

A router connects different networks to each other and forwards traffic between them using IP addresses — it is how your local network reaches the internet. A switch connects devices within the same network, forwarding frames to the correct port based on MAC (Media Access Control) addresses. An access point (AP) bridges wireless clients onto that same wired network — it converts Wi-Fi radio traffic into Ethernet, but it does no routing of its own. The three are often combined into one home “router,” which is exactly why candidates mix them up.

For the 220-1201 exam you need to keep the roles separate, because business networks separate the boxes: a firewall and router at the top of the rack, one or more switches in the middle, and access points ceiling-mounted around the building. The exam’s networking-hardware objective asks you to compare these devices, and its PBQs ask you to label them in a diagram — the full 220-1201 study guide shows where the Networking domain sits in the overall exam. Both formats get easy with repetition — the Core 1 exam bank drills them.

The router: traffic between networks

A router’s job is deciding where packets go next when the destination is not on the local network. It reads the destination IP address, consults its routing table, and forwards the packet toward the right network — typically your ISP (Internet Service Provider) on one side and your LAN (local area network) on the other. Because it sits at that boundary, the router is also where several boundary services naturally live:

• NAT (Network Address Translation) — translating many private internal IP addresses to the one public address the ISP assigns.
• DHCP (Dynamic Host Configuration Protocol) — handing out IP addresses to local devices, on small networks.
• The default gateway role — every PC on the LAN points at the router’s internal IP as the way out.

Hands-on tell: the router is the device with an Ethernet run heading toward the modem or ONT (optical network terminal), plus a connection down into the switch. If a device’s uplink leads out of the building, you are looking at the router.

The switch: traffic within a network

A switch is the wiring hub of the LAN. Every wired desktop, printer, server, and access point plugs into a switch port. When a frame arrives, the switch reads the destination MAC address, looks it up in its MAC address table (learned automatically by watching source addresses), and forwards the frame out only the port where that device lives. That per-port intelligence is what separates a switch from the obsolete hub, which blindly repeated every frame to every port and forced devices to share bandwidth.

Two variants matter on the exam:

• Unmanaged switch — plug and play, no configuration. Fine for a desk cluster or a small office.
• Managed switch — configurable via a web interface or console: VLANs (virtual LANs, which split one physical switch into isolated logical networks), port monitoring, link aggregation, and PoE (Power over Ethernet), which pushes DC power down the data cable to run access points, IP cameras, and VoIP phones without separate power bricks.

Hands-on tell: the switch is the box with the most ports — 8, 24, or 48 — usually sitting directly below a patch panel with short patch cables between them.

The access point: wireless onto the wired network

An access point takes 802.11 wireless traffic from laptops, phones, and tablets and bridges it onto the Ethernet network. It broadcasts an SSID (Service Set Identifier — the network name), authenticates clients, and converts between radio frames and wired frames. What a standalone AP does not do is route, translate addresses, or assign IPs: it hands wireless clients to the same switch-and-router infrastructure that wired clients use, so a phone on Wi-Fi gets its DHCP lease from the same server a desktop does.

In a business deployment, APs are mounted on ceilings for coverage and fed by a single PoE cable each — power and data down one run. Multiple APs broadcast the same SSID so clients can roam. In a home, the “wireless router” is really a router, a small switch (the four LAN ports), and an AP sharing one plastic box; if you’re configuring one of those combo units, the SOHO wireless router setup walkthrough covers the software side.

Router vs switch vs access point

	Router	Switch	Access point
Core job	Forwards traffic between networks	Forwards traffic within a network	Bridges wireless clients onto the wired network
Forwards based on	IP addresses (routing table)	MAC addresses (MAC address table)	Associations between Wi-Fi clients and the wired uplink
Typical position	Network edge, behind the modem/firewall	Middle of the rack, below the patch panel	Ceiling- or wall-mounted, one Ethernet uplink
Common extras	NAT, DHCP, default gateway	VLANs, PoE, link aggregation (managed models)	SSID broadcast, client authentication, roaming
Ports	Few (WAN + LAN)	Many (8–48)	Usually one uplink (often PoE-powered)

The supporting cast in the rack

Diagram-labeling questions rarely stop at three devices. Know the roles of the neighbors:

• Modem / ONT — converts the ISP’s medium (cable RF, DSL, or fiber light) into Ethernet. It terminates the provider connection; it does not route or switch your LAN. Sites without wired service substitute a cellular WWAN modem in this position.
• Firewall — inspects traffic against security rules and blocks what fails. In small networks it is a feature inside the router; in business racks it is a dedicated appliance sitting between the router and the switch.
• Patch panel — a purely passive termination point. The building’s in-wall cable runs land on its rear; short patch cables connect its front ports to switch ports. No power, no intelligence — it exists so you re-plug patch cables instead of re-terminating wall cabling.
• PoE injector — adds power to a single Ethernet run when the switch itself is not PoE-capable, typically to feed one AP or camera.
• Hub — a legacy repeater that floods every frame to all ports. On the exam it appears as the wrong answer next to “switch.”

How the 220-1201 exam tests this

• Rack-diagram PBQs. An interactive item shows a rack or floor-plan diagram and a bank of role descriptions — “forwards frames by MAC address,” “connects the LAN to the ISP,” “provides wireless connectivity” — and you drag each device name onto its role. Anchor yourself with the cable paths: toward the ISP = modem then router; the many-port box = switch; the ceiling device = AP.
• Best-device scenarios. A stem describes a need — add eight wired drops to an office, extend Wi-Fi to a warehouse, connect two subnets — and asks which device satisfies it. Match the need to the core job: more wired ports = switch, wireless coverage = access point, between-networks traffic = router.
• Layered distractors. Expect answer choices that pair a correct device with a wrong function (“a switch assigns IP addresses”) or attribute NAT and DHCP to an AP. Functions travel with the device, not with the box they happen to share in a home unit.

Quick reference

• Router: between networks, decides by IP address, hosts NAT/DHCP/default gateway at the network edge.
• Switch: within a network, decides by MAC address, provides the wired ports; managed models add VLANs and PoE.
• Access point: bridges Wi-Fi clients to the wired LAN; broadcasts the SSID; does not route or assign addresses.
• Home “wireless routers” combine all three roles in one box; enterprise networks split them into separate devices.
• Patch panels are passive; hubs are obsolete repeaters; modems/ONTs terminate the ISP line.
• PoE lets a switch (or injector) power APs, cameras, and phones over the data cable.