Networks operate on the principles of communication and sharing. That means network traffic and data could be accessed by people who have no authority to do so. Network security can be improved by implementing different techniques which help to prevent cyberattacks.
Networks operate on the principles of communication and sharing. Unfortunately, these principles mean that network traffic and data risk being accessed by people who have no authority to do so, ie hackers.
A network and the servers connected to it are likely to contain large amounts of information. This information could be valuable and some of it is likely to be private and confidential. For example, a school network is likely to have:
This information needs to be kept secure and most of us wouldn’t be happy if our personal information was available to people who didn’t need it.
There are many ways to secure a network but the starting point is only allowing network access to authorised people. This is known as authentication and validation. A person will authenticate themselves using a username and password. Before being given access to the network, a server will validate their username and password against a list of authorised users.
There are other methods of authentication and validation such as using PINs, a fingerprint or facial recognition.
Authentication of users isn’t enough to fully secure a network. Other important security measures are access control, firewalls and physical security.
Access control determines the facilities a user has access to, such as:
A network manager should restrict most users to allow them to access only the facilities they need. For example, an office worker might need access to productivity software, email and the internet, but not to install software or access to other users' accounts. Restriction limits the actions a user can take, reducing the potential of threats. The restrictions can be precise, allowing different people access to different sets of files or information.
A firewall is a tool that monitors traffic going into and out of a computer or network, and either allows the traffic to pass through or blocks it.
The decision to allow or block traffic is based on rules, known as the firewall policy. For example, some programs, such as email clients and web browsers, have legitimate cause to send a transmission. These programs are known to the system and the firewall policy allows their communications. However, any transmissions that are not sent from, or to, known and allowed sources are blocked.
Firewalls can be hardware-based or software-based. Hardware firewalls tend to be more expensive, but are more effective.
Physical security means restricting physical access to important parts of a network. For example, servers should be kept in a locked, secure room that can only be accessed by authorised people, such as the network manager.
This is important as anyone with physical access to a server could remove or access the hard disks containing private and confidential information.