Discovering computer networks: hands on in the Open Networking Lab
Discovering computer networks: hands on in the Open Networking Lab

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

Free course

Discovering computer networks: hands on in the Open Networking Lab

6.1 Switching

In this part you will see how a home gateway acts as a switch to connect devices on a home network.

Now watch the video below, which is about 2 minutes long.

Switching

Download this video clip.Video player: 34_switching.mp4
Skip transcript

Transcript

Welcome to a session about home gateways. In this session you will see that a home gateway carries out several different tasks. On a managed network in a business context, these might be carried out on several different devices; a home gateway won’t be as fast or powerful as these, but it is quite a sophisticated device.

I’ll start with something simple – a new network with a gateway router, a desktop, laptop and tablet, and I’m going to use wired connections first.

Initially I’m going to set up static IP addresses manually. What addresses should I use? It’s best to stick to the private address range because you won’t be popular if your IP address conflicts with Google or Facebook – or maybe you’ll be very popular.

So I’m going to set my desktop to IP 192.168.0.10 and my laptop to 192.168.0.20.

Now I can connect them to the router with Ethernet cables. So from the Ethernet port to the first free Ethernet port on the gateway, and then from this Ethernet port to the next free Ethernet port on the gateway.

So let’s see if I can ping between machines. I’ll type ipconfig to check my own IP address, and then ping 192.168.0.20, the address I set for my laptop. And there are some return pings, so I do have a network connection.

The gateway here is operating as a switch, nothing else. It learns which machines are connected and will pass packets to the correct destination.

The gateway router itself is a device on the network and it has its own IP address. But what is it?

With luck, the gateway will have set itself up with a default IP address that is well known and documented in the manual. Here I know it is 192.168.0.1 and I should be able to ping from my desktop to confirm that the router is responding. And there we are.

So we have a local network set up, and the gateway is acting as a switch transferring data between devices within the LAN.

End transcript
 
Interactive feature not available in single page view (see it in standard view).

The home gateway incorporates a switch that connects devices within the LAN, using either wired or wireless connections. The gateway itself has an IP address on the LAN, usually set up to a known default value.

Activity 1 Test yourself

An ISP may send out thousands of similar home gateways to its customers. Can they all be given the same LAN IP address?

a. 

Yes.


b. 

No.


The correct answer is a.

Answer

Home networks are set up with addresses in a private range (often IP addresses starting 192.168.0.0) so it doesn’t matter if gateways in different networks have the same address. Each home network will only have a single gateway.

OPNL_1

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus