Routers, Gateways, and Modems. What's the Difference?

When talking about networks you can hear loads of different terms: Routers, Gateways, Modems. It gets even more confusing when these terms are used in very similar topics.

1. Modems

Let’s start our discussion from Modems. A modem is one of the oldest terms used when talking about Networks. A modem is a piece of hardware built solely to do one task and one task only – send traffic from point “A” to point “B” without doing anything with data. Historically, Modems are considered primitive devices that are not programmable thus data security services and traffic routing capabilities are not present in such devices. Moreover, Modem works like a key, a key to the internet. Similarly, to a key, majority of Modems cannot make a connection without the help of software running on the device it is connected to.

2. Routers

Routers, similarly as Modems are used to provide and manage internet connection. When router is used, there is no additional need to use another device to control it. Routers can and do provide internet connection autonomously. Moreover, Routers can provide internet connection to multiple devices through multiple interfaces. They possess data routing capabilities allowing to provide internet access to multiple devices simultaneously. This capability of handling multiple interfaces and various devices connected to it makes Routers very versatile and adaptable to a use case scenario. Another massive difference between Modems and Routers is software functionality. Routers are usually equipped with advanced data security services such as firewalls and multiple data tunneling services. These features provide extensive data security and lower risk of cyber attacks. All in all, Routers are best defined as Networking devices that do provide a secure internet connection to multiple devices simultaneously. 

3. Gateways

Lastly, let’s have a look at Gateways. Gateway is a term widely used and quite often misused while talking about networks. Term Gateway gets often mixed up with term Router and there is an excellent reason why. They are very similar. When you look at the functionality of majority of Gateways and Routers you will find many similarities. Both Routers and Gateways work autonomously; both are usually equipped with extensive security functionality such as firewall and data tunneling capabilities.

So how are they different? The principal difference between Routers and Gateways is number of interfaces it can support. While Routers are designed to manage multiple interfaces, Gateways usually are designed to have only one interface. Thus, it can be said that Routers are meant to connect multiple devices to internet and Gateways are meant to connect only one device.