Różnica między modemem a routerem

What Is the Difference Between a Modem and a Router?

Although a modem and a router may look similar, each serves a different purpose. Both are essential devices for connecting to the internet. A modem is not the same as a router, and if you need a reliable internet connection, it’s good to understand the differences between them. In this article, we explain what a modem and a router are and how they differ from each other.

What Is a Modem?

A modem serves as the link between the internet and your computer. It is responsible for converting or translating signals — it modulates and demodulates the internet signal. It converts the computer’s digital signal into an analog one that travels through cable connections, and then changes it back into digital form (ones and zeros) on the receiving end.

A modem can connect to various types of infrastructure - cable, telephone, satellite, or fiber optic.

A wireless modem allows you to connect to the internet wirelessly, without needing cables. This type is often called a WiFi modem.
A cable modem provides an internet connection via cable.

In combination with other devices, such as routers, modems can form a fully functional and connected network that allows us to communicate and access the internet.

Simplified diagram of modem functionality

What Is a Router?

A router is a device that connects multiple networks and directs network traffic between them. It is located between the internet connection and the local network.

Beyond basic data routing, routers can also provide additional features such as network security, Quality of Service (QoS) management for prioritizing specific types of traffic, and firewalls to protect the network from unauthorized access.

A router allows multiple devices to share a single internet connection. The connected devices can communicate with each other using the local network. The router tracks which traffic is going to which device and assigns each device an IP address. It recognizes the destination address of data packets and decides the most efficient path for delivery.

Types of Routers According to Internet Connection

• Wired routers – connect to the internet using an Ethernet cable. Suitable for fixed connections like DSL, fiber optic, or cable internet.
• WiFi routers – create a wireless network (WiFi) in addition to wired internet access, enabling cable-free device connection.
• Mobile routers – connect to the internet through a SIM card with a data plan and create a WiFi network. Ideal for mobile use or areas without fixed connections.

Simplified diagram of router and local network functionality

Comparison: What Each Device Does

• A modem is responsible for translating the signal, while a router manages transmission, reception, and security.
• A modem can function alone, while a router depends on a working modem.
• A router connects devices to the internet only when the modem is active.
• A modem connects a single device to the internet via an Ethernet cable (or USB connection today). To connect multiple devices, a router must be used.
• A modem transfers data exactly as it receives it from the internet, without checking it.
• A router typically includes firewalls to inspect and filter data packets.

Example of a Robustel router

Two-in-One Devices

Nowadays, you don’t necessarily need two separate devices — manufacturers often integrate a modem directly into a router.

Modem vs Router

While a modem serves as a gateway bringing the internet into your home, the router ensures that the connection is efficiently and securely distributed among your various devices.

We will gladly assist you in selecting a suitable modem or router. Contact us at sales@sectron.cz.