We’ve just learned how the router uses its routing table to send packets from one network to another. So far, we haven’t needed to use this, as we’ve only been simulating communications within one IP network. In this architecture, there is no need for a router.
However, when a device wants to send a packet to other networks, it needs to know the router’s IP address of the router responsible for passing on the data to its destination network. If we take the network we’ve just been using, we need to set a default gateway for the three PCs.
Device | Output interface | Default gateway |
PC0 | 192.168.30.1 | 192.168.30.254 |
PC1 | 192.168.10.1 | 192.168.10.254 |
PC2 | 192.168.20.1 | 192.168.20.254 |
Join me in the video below to see how to do this!
Configure Your Equipment with Cisco Packet Tracer
You’ve done it! You’ve learned all the skills you need to successfully complete your mission for Tinos driving school.
Here’s the architecture as it stands:
At this stage, you have:
Created the network architecture with all the necessary equipment and cables.
Assigned an IP address to all end nodes.
The next step is to configure Cyclade’s PCs so that they can access Tinos’ file server.
Over to You!
Go back to your architecture and carry out the following steps:
Enable the router’s network interfaces.
Assign an IP address to them.
Set a default gateway for all end nodes.
Test communication between Cyclade’s two devices and Tinos’ server. You can use the ping or packet simulation method.
Answers
You can find the answer sheet here and watch the video below to check your work.
Each piece of equipment within a network operates on a different level of understanding. These levels or “layers” are all represented within the OSI model—this is what the next chapter is all about.
A message traveling through a network contains a lot of information to ensure it arrives at the right destination. Each network device understands different types of information contained within the message.
Let’s Recap!
For a device to send packets to an external network, we have to provide it with the IP address of the default gateway, i.e., the IP address of the router used to pass on the packets.
In Packet Tracer, all you have to do is fill in the “Default Gateway” field in the device configuration.
All packets this device then sends to an external network will travel via the gateway, which will route them correctly.
To make this clearer, we’ll look at how standardization rules and models keep communication consistent in the next chapter.
