Programs that are meant for engineering professionals never are easy to learn- but practice makes perfect! Packet Tracer is a good example of a tough program released by Cisco, of which even making a small computer network can pose a challenge.
Two computers that are connected through a router are actually on separate networks if properly configured. Having a computer communicate another on a different network is a complex process, but Packet Tracer makes it easy to setup the design and configuration.In about 10-15 minutes, the most basic of all networks can be constructed and working.
Constructing the network will take two crossover cables and a console cable. The two crossover cables will connect each desktop to the Ethernet ports of the router, while the console cable will connect one of the computers to the router for configuring. Be sure that the cable you are using isn’t a straight-through when using your Ethernet cable, as this type of cable is reserved for unlike devices.
Each of the computers on the network will need an IP address for routing information from one network to another. You will also have to assign an IP address to each Ethernet port of the router. The Ethernet port connected to a single desktop machine will share the same network address, but will have a different host address. There will be two separate networks; one on each of the Ethernet ports. The IP address you assign may not be a reserved number or duplicated among ports.
The gateway address is also very important: it allows a computer to connect to a network. The gateway address is configured on the desktop, and it’s value is the same IP address as the Ethernet interface that it is connected to. Without the gateway, information wouldn’t have a way of getting from one network to another. It’s one of the most common rookie mistakes to accidentally leave the gateway address blank.
We can confirm that the network was set up properly by pinging a computer from another. As long as you did everything correctly, you should get a success message when using the command line interface. If you get an error regarding a time out, odds are you have input the wrong IP address information or forgot to open the Ethernet ports of the router. Troubleshooting is a valuable skill to have, so try to fix the problem yourself before asking for help if you get stuck on a problem.
Final Thoughts
The small network described is functional, and is even used in real world applications. Using Packet Tracer will simplify the process of designing the network so that you can save time in the overall process, and put more time into troubleshooting and problems that arise during the course of the implementation.
Learn more on packet tracer tutorial and packet tracer router.