Difference between router and switch

A switch connects devices within one local network so they can talk to each other, while a router connects separate networks together and gives those devices access to the internet.

Below are how each one works, their types and advantages, how they compare with hubs, modems, access points and firewalls, and how to add a switch to your router.

Router vs switch: the key differences

Cisco sums up the split in one line: switches allow different devices on a network to communicate, and routers allow different networks to communicate.

Feature	Router	Switch
Main job	Connects networks and shares one internet connection	Connects devices inside one local network (LAN)
Addresses it reads	Destination IP address	Destination MAC address
OSI layer	Network layer (layer 3)	Data link layer (layer 2)
Internet access	Yes, links the LAN to the internet	No, it needs a router for that
Typical ports	One internet (WAN) port plus a few LAN ports	Five to 52 Ethernet ports on fixed models
Wi-Fi	Built in on home wireless routers	Not usually; add an access point
Security features	Firewall, content filtering, guest networks, WPA2 Wi-Fi	Managed models add VLANs and security settings; unmanaged have none
Where it sits	At the edge, between your network and the internet	Inside the network, plugged into a router port

What is a router?

A router receives and sends data on computer networks and connects networks to each other, including your home or office network to the internet. Cisco describes it as a dispatcher that directs traffic and chooses the most efficient route for each data packet.

Most home routers combine several jobs in one box, which is why they get confused with modems, hubs and switches.

Type of router	What it does	Where you find it
Core router	Carries maximum bandwidth between other routers and switches	Internet service providers, cloud providers and very large enterprises
Edge (gateway) router	The network's outermost link to external networks such as the internet; usually Ethernet ports only	Where the network meets the provider
Distribution (interior) router	Takes data from the edge router and sends it to users, often over Wi-Fi	Inside larger networks
Wireless router (residential gateway)	Combines edge and distribution roles with Wi-Fi	Most homes and small offices
Virtual router	Router functions delivered as software in the cloud	Large businesses with complex networks

How does a router work?

Every data packet carries a header with the sender, data type, size and, most importantly, the destination IP address. The router reads that header, prioritizes the packet and picks the best route for it.

Router function	What it gives you
Packet routing by IP address	Data reaches the right network, local or across the internet
Internet sharing	Many users and devices share one internet connection
Traffic priority	Decides which devices or kinds of traffic go first
Built-in firewall and content filtering	Extra protection from unwanted content and malicious websites
Guest network	Visitors get Wi-Fi without reaching your own devices and files
USB storage and printer sharing	On many models, a drive or printer becomes available to the whole network

Advantages of a router follow from those functions: one internet connection for every device, separate networks that stay apart, and a security layer at the edge. On a home network, the router is also where you change Wi-Fi settings, such as the WPS button and pairing.

Routers help a business in the same ways: they connect employees to the local network and the internet, screen out malicious websites with built-in firewall and content filtering, and turn an attached hard drive or printer into a shared resource for the whole office. The types of routers in the table above show which class fits a home, a small office or a large enterprise.

What is a switch?

A network switch connects devices such as computers, printers, servers and wireless access points within one local area network. It works at the data link layer and forwards each packet only to the device it is meant for, using the destination MAC address.

Switches fall into two categories: modular switches, which take expansion modules, and fixed-configuration switches with a set number of ports.

Type of switch	What it offers	Best for
Unmanaged	Plug and play, no settings and no security features	Homes, a desk, a lab or a meeting room that needs more ports
Smart (smart managed)	Some management, segmentation, quality of service and security	Small businesses on a budget
Managed	Fully configurable: VLANs, QoS, security settings and performance data	Larger networks where reliability and security matter
Modular	Expansion modules for firewall, wireless, extra ports or power	Networks that change; costs the most
PoE switch	Powers IP phones, cameras and access points over the data cable	Devices in places without a power outlet
Stackable	Several switches managed as one unit that routes around a failed member	Growing networks

How does a switch work?

A switch learns which device sits on which port and stores that in a MAC-address table. When a packet arrives, it sends it out of the one port that leads to the destination device instead of to every port.

Advantage of a switch	Why it matters
More usable bandwidth	Several devices can communicate at the same time
Less congestion than a hub	Data goes only to the device that needs it
Separate collision domain per port	Traffic from one device does not collide with another's
Traffic isolation and VLANs	Managed switches split one physical network into secure virtual networks
Easy expansion	Add ports by connecting another switch to the router or to an existing switch
Speed choices	Fast Ethernet (10/100 Mbps), Gigabit (10/100/1000 Mbps), 10 Gigabit and up to 40/100 Gbps

Router vs switch vs hub

A hub is the oldest of the three: a central connection point for devices in a LAN that shares its bandwidth between everything plugged in.

Device	How it forwards data	Effect
Hub	Shares bandwidth across all connected devices	The more devices you add, the longer data takes to arrive
Switch	Sends each packet only to its destination port, using MAC addresses	Avoids the hub's slowdowns and collisions
Router	Sends packets between networks, using IP addresses	Connects the LAN to the internet and to other networks

Router vs switch vs modem, access point, gateway and firewall

Home internet kits often combine several of these devices in one box. Each still has a distinct job.

Device	Job	How it relates to a router and a switch
Modem	Connects your network to the internet provider's line	Cisco notes that edge router and modem are somewhat interchangeable terms; the router sits behind it or is built in
Wireless access point (AP)	Lets Wi-Fi devices join a wired network	Plugs into a switch or router port and extends Wi-Fi coverage
Gateway	Connects different networks by translating between protocols	The Wi-Fi router from an internet provider is both a router and a gateway
Firewall	Allows or blocks traffic based on security rules	Many routers have one built in; businesses add a dedicated device
Switch	Connects devices inside the LAN	Adds wired ports behind the router

Do you need a router or a switch?

Your situation	What you need	Why
New internet connection, no network yet	Router (often supplied by the provider)	Only a router shares internet access between devices
Router has run out of Ethernet ports	Unmanaged switch	Plugs into one router port and adds more wired ports
Wi-Fi is weak in part of the building	Access point or mesh system	A switch adds wired ports, not wireless coverage
Need separate networks, such as staff and guests	Router with guest network, or a managed switch with VLANs	Keeps traffic apart
IP cameras or phones with no power outlet nearby	PoE switch	Sends power and data over one cable

How to connect a network switch to a router

An unmanaged switch needs no configuration, so adding one takes a few minutes.

1. Place the switch near the devices you want to wire up and plug in its power adapter.
2. Connect an Ethernet cable from a free LAN port on the router to any port on the switch.
3. Connect each wired device, such as a desktop PC, printer or game console, to another port on the switch.
4. Wait for the port lights on the switch to show a link for each connected device.
5. On a managed switch, sign in to its management page and set up VLANs or quality of service if you need them.

Do not plug the switch into the router's internet (WAN) port; that port is meant for the modem or the provider's line.

How to check a device behind the switch reaches the router

1. On a Windows PC connected to the switch, open Command Prompt.
2. Type ipconfig and press Enter.
3. Under the Ethernet adapter, confirm an IPv4 Address appears and Default Gateway shows your router's address.
4. Open a website to confirm internet access passes through the switch and router.

If the PC shows no default gateway, check its IP and Ethernet settings before you blame the switch.

On a Mac connected to the switch, find the router's IP address in network settings to run the same check.

Router vs switch FAQ

What is a router vs a switch?

A router connects different networks and shares an internet connection between devices, using IP addresses. A switch connects devices inside one local network so they can exchange data, using MAC addresses. Most networks use both.

Can a switch replace a router?

No. A standard switch only connects devices within one network and cannot share an internet connection. You still need a router to reach the internet; the switch plugs into it to add more wired ports.

Is a Wi-Fi router also a switch?

Yes, in practice. A home wireless router combines a router, a small built-in switch for its LAN ports, a Wi-Fi access point and usually a firewall in one box.

What is the difference between a router, a switch and a hub?

A hub shares bandwidth across all devices, so it slows down as you add more. A switch sends data only to the destination device. A router connects whole networks together and to the internet.

What is the difference between a router, a switch and a modem?

The modem connects your network to the internet provider's line, the router shares that connection and directs traffic, and the switch adds wired ports for more devices inside the network.

Is a switch the same as an access point?

No. A switch connects wired devices with Ethernet cables. A wireless access point lets Wi-Fi devices join a wired network, and it usually plugs into a switch or router port itself.

Does a switch slow down the internet?

A switch does not limit your internet speed as long as its port speed matches your connection. Use a Gigabit switch for gigabit internet, because a Fast Ethernet switch tops out at 100 Mbps.

Router vs switch in networking: which OSI layer?

A switch works at layer 2, the data link layer, and forwards frames by MAC address. A router works at layer 3, the network layer, and forwards packets by IP address.

Router or switch: which one should you buy?

Get a router first for internet access, and add an unmanaged switch only when you run out of wired ports. The router is the only device that shares one internet connection across the network, while a switch simply extends it with more Ethernet ports.