Setting the Scene
Before you commence this <1h microcourse - you need to be aware that Cisco Packet Tracer is free, free for everyone - students, teachers and of course education establishments.
You will need to download/install this before you commence. Cisco offer this via ...
Versions exist for Windows, Linux and the Mac.
Andrew Smith - from the Open University Cisco Academy Support Centre (OUCisco) has created this ad-hoc resource for everyone. He will refer to teachers and students separately as this activity can be accomplished both online and in the classroom.
Above is a brief introduction from Andrew Smith ... it is under 30 seconds ... please take the time to watch this and then scroll onwards.
Getting started!
We will assume that you have a recent version of Packet Tracer installed - this should work with all versions. However, the later the version - the better the experience. As shared in getting started (scroll up) - anyone can obtain and install packet tracer for free.
By default, Cisco Packet Tracer requires you to login to NetAcad - this is essential if you wish to save this activity at any time. Be careful, the login is case fussy.
You may notice some minor differences in appearance. Everything being demonstrated, was created using v7.2.2
First you will be greeted with a blank canvas - soon, you will add a server, a switch and two PC's. This will be a simple network, however you will be accomplishing a great deal with these few devices.
You will build this network in stages, first setting up DHCP, then DNS, then a web server, finally you will set up email.
Make sure that you save the file regularly - this may seem obvious. However, our experience is that some of you forget then become upset when it goes badly wrong.
Note for teachers - your students will cover a number of different concepts and technologies in this session. The aim is to give them a simple 'real' network. We will not explain how all of the technologies 'actually' work - we can leave that to you. However, we will show the students 'how to make them work'.
First - let's get DHCP working.
DHCP ... dynamic host configuration protocol - allows a server (or a router, such as your home wireless device) to allocate IP addresses to all end devices on a network. This is why you are able to enable a connection between your smartphone and a cafe wifi hotspot - without needing to add an IP (internet) address.
Step one, is to ensure that the server has its own IP address.
For this activity, we will issue 10.0.0.1 to the server, as well as a subnet mask of 255.0.0.0 to keep it simple. Also, do not forget to tell it (the server) that its DNS address will be 10.0.0.1 - you will require this later on.
Step two, you need to set up the DHCP pool, this is a collection of IP addresses. Click on the server and select services.
As you can see from the serverPool configuration. You must 'switch on' the DHCP server, tell the pool the start address, subnet mask and DNS before you save the configuration.
Note for teachers - no, we have not missed the default gateway. This network does not require it. Why is this? A challenge for both you and your students to discover.
Step three, enable DHCP addressing on each PC ... this is very easy, all you need to do - is click on the DHCP radio button. Technology will do the rest for you.
You may add as many PC's as you desire - however, please do not do this. Two PC's are more than enough for this activity.
Finally, you may test connectivity, by using command prompt on PC0 to ping PC1 ... the coam
As you can see from the above video, pinging from PC0 to PC1 is simple - you may also ping the server.
NEXT - set up DNS and also a web server!
We will need a web server so that our DNS entries are interesting ... within the server on packet tracer. There is a nice, basic web server that is always on by default.
You will notice that the web server is exceptionally simple to set up. You may edit the pages using a very basic form of HTML - it is worth checking the Packet Tracer help files for a full exploration of what HTML is available.
Note for teachers ... why did the browser allow me to visit the server on 10.0.0.1 - discuss this with your students.
Next, we need to set up DNS - this is a domain naming system technology that matches human understandable names to IP addresses. So www.cisco.com or www.open.ac.uk are all domain names and map to specific IP addresses.
Another note for teachers - there are many conventions and standards around domain names - you may wish to explore the role of an internet registrar.
In the next video, you will see Andrew set up the DNS server. Do not forget to switch this on - it is off by default. Create a simple entry of www.supercool.com and point this to the 10.0.0.1 IP address of the server. This will link the web server to this IP address.
As you can see from the above video - this wasn't difficult. It is essential to note, that the required A record was available by default.
Note for teachers - there are many different types of DNS records, Packet Tracer uses four of these. Explore with your students - what they are as well as why they are required?
It is time that you take a moment to stop and think! So far, you have:
- Built a Network
- Enabled IP addressing via a DHCP pool
- Set up a basic web server
- Set up a DNS server and a single domain
- Browsed to the web server via the DNS and DHCP configured network
You are doing well - all you now need to set up is email. Please scroll down.
Setting up an email service!
Setting up the email server is a two stage process on Packet Tracer:
- First, you must set up another DNS based A record for the email clients - for fun, we are going to call it 'mail.me'
- Then, you must set up the email server and create at least two email accounts ...
After this you will also have to set up the clients. But not yet, first complete the setting up of the server service.
First, you need to set up your 'mail.me' DNS based A record. It must point to 10.0.0.1 - we can have many services running from the same server. We can also have many DNS entries for many domains also pointing to the same server.
Next, you must work on the email service within the Packet Tracer server.
As you can see - the SMTP and POP3 services are also switched on by default. However, it is worth checking to ensure that this is the case. SMTP is for Simple Mail Transport Protocol - this supports sending mail. POP3 is Post Office Protocol v3 and supports the receipt of email.
You need to set the mail domain of mail.me - hence why you had to create this A record in DNS. Then create two accounts Bob and Alice - they are classic tropes in computing (why not search the internet to understand where they are often used). For each account, we have used the classic password of 'cisco' - no good security here is there - however, it is easy to remember for the purposes of this practical activity.
Now you are ready to set up the email clients. Please read on.
Note for teachers - why not ask your students to explore in greater detail SMTP and POP3 - for SMTP there is an actual command set.
Setting up an email client
Now you need to work on both PC's - PC0 will be 'Bobs Computer' - PC1 will be 'Alices Computer'.
To set up bob, you go to the desktop tab, then email - the following video explains more in greater detail.
You must set up the server - mail.me and the email address of bob@mail.me - of course, you already know that the super secure password is 'cisco'.
Next, you will set up Alice, who will email Bob. There is some repetition of the previous video - however, you MUST pay attention as there are some essential differences. Also - Alice will show you how to email Bob.
Once you have set up Alice, you can email bob@mail.me - then Bob can reply to alice@mail.me.
Note for teachers - ask your students to add two more PC's and two additional email accounts (why not call them Fred and Wilma). They will need to check back through the relevant steps to complete this. Then ask them to email you their PT file with additional proof that Fred, emailed Bob then Alice and finally Wilma about his friend Barney (make sure the students keep it decent).
We are are working with our WhatsApp - Cisco Instructor community to develop and share other micro activities for teachers during the Covid19 lockdown.
Credits:
Created with images by Umberto - "Optical fibers colored lamp" • Grzegorz Walczak - "untitled image" • Smart - "Man On Arrow" • paul jespers - "untitled image" • Thomas Jensen - "Homelab backbone" • Markus Spiske - "Code on computer monitor" • Free To Use Sounds - "Stop sign near Denver airport" • Bundo Kim - "Post" • Adi Goldstein - "Pointing As You" • Kon Karampelas - "iPhone displaying the gmail app"