Introduction to cyber security: stay safe online
Introduction to cyber security: stay safe online

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

Introduction to cyber security: stay safe online

2.1 Network security challenges

Internet routers are designed to move datagrams to their destination but how secure are they?

They have been programmed with strategies to overcome problems such as congestion or the failure of a part of the network. These strategies involve re-routing datagrams via any alternative path, as you saw from using Trace Route. Therefore, it is impossible to state with any assurance which route will be taken by a datagram travelling outside a local network.

The datagram may travel directly, or, more probably, travel through several routers located anywhere in the world. These routers will most probably not belong to either the sender or the recipient, but a third party. In most cases this will not matter, but datagrams can be copied, and their security compromised, as they pass through a router without alerting either the sender or receiver.

The process is known as packet sniffing and it has many legitimate purposes including analysing network performance and for law enforcement, but packet sniffing software is readily available to anyone who chooses to use it. In the past, packet sniffing required a computer that was wired to the network, but wireless networking means this is no longer the case.

CYBER_B1

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, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 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 prospectus371