Network Security: What Is It, Why Does It Matter and What Can You Do to Make Networks More Secure?

Today, hacks, data breaches, and cyberattacks are more common than ever before. In fact, the number of data breaches that exposed private records more than doubled between 2015 and 2017 alone.
The increasing number and severity of these attacks make network security a topic of utmost importance, especially for current and prospective certified IT professionals.

CompTIA has done extensive research on cybersecurity, and one recent study on building security teams, shows that the primary driver for a new security approach
is a change in IT operations. Migrating to a cloud provider, adding new mobile devices or focusing on data analytics are all common IT strategies that require new security tactics. It’s no coincidence that these strategies also drive changes
or improvements to the corporate network. Success in these areas requires a solid understanding of best practices in network security.

Network security is a smaller subset that falls under the larger umbrella of cybersecurity, and it refers to the practice of preventing unauthorized users from accessing computer networks and their associated devices. It involves physically protecting
network servers and devices from external threats, as well as taking steps to secure the digital network. In an age of increasingly sophisticated and frequent cyberattacks, network security matters more now than ever before.

The Importance of Network Security

Network security is vital to maintaining the integrity of your data and the privacy of your organization and employees. It encompasses everything from the most basic practices,
such 
creating strong passwords and fully logging out of community computers, to the most complex, high-level processes that keep networks, devices and their users safe. More and more sensitive information
is stored online and in these various devices, and if an unauthorized user gains access to that data, it could lead to disastrous results.

Network security is the key to keeping that sensitive information safe, and as more private data is stored and shared on vulnerable devices, network security will only grow in importance and necessity. Experts expect that more than 2,314 exabytes (or over 2 trillion gigabytes) of data will exist by 2020; managing that amount of data is difficult enough, and protecting it will be another issue entirely.

While each and every member of your organization can take strides to help keep things secure, network security has become more complex in recent years. Adequately protecting networks and their connected devices requires comprehensive network training,
a thorough understanding of how networks actually work and the skills to put that knowledge into practice. It’s crucial for networks to be thoroughly and properly set up, secured and monitored to fully preserve privacy.

Common Network Security Vulnerabilities

In order to effectively implement and maintain secure networks, it’s important to understand the common vulnerabilities, threats and issues facing IT professionals today. While some can be fixed fairly easily, others require more involved solutions.

Virtually all computer networks have vulnerabilities that leave them open to outside attacks; further, devices and networks are still vulnerable even if no one is actively threatening or targeting them. A vulnerability is a condition of the network or
its hardware, not the result of external action.

These are some of the most common network vulnerabilities:

• Improperly installed hardware or software
• Operating systems or firmware that have not been updated
• Misused hardware or software
• Poor or a complete lack of physical security
• Insecure passwords
• Design flaws in a device’s operating system or in the network

While a vulnerability does not guarantee that an attacker or hacker will target your network, it does make it much easier — and possible — for them to gain access to it.

Physical Security Considerations

You must also consider the physical security of the various devices, servers and systems that are used to power and maintain your network. If a network is physically vulnerable, it doesn’t matter how strong or extensive its security is, because
if someone can gain physical access to any of these items, the entire network could then be compromised.

Important physical safety considerations include the following:

• Storing network servers and devices in a secure location
• Denying open access to this location to members of your organization
• Using video surveillance to deter and detect anyone who attempts to access this location

Taking precautions to maintain the physical safety of your network will ensure that it’s able to run as smoothly and safely as possible.

Types of Network Security Attacks

Over the last several years, cyberattacks have become more sophisticated, extensive, frequent and more difficult to defend against. Many cybersecurity experts believe that these attacks will only continue to grow more complex and aggressive.

Some of the most prevalent types of network security attacks any IT professional should be aware of include the following:

• Data Theft: Also called data exfiltration, data theft occurs when an attacker uses their unauthorized access to obtain private information from the network. Attackers frequently use stolen login credentials to read protected files
  or steal the data while it is in transit between two network devices.
• Insider Threat: As its name implies, insider threats come from employees within an organization. These employees use their own access to infiltrate the network and obtain sensitive or private company information.
• Malware Attacks: A malware attack occurs when a malicious code (malware) inserts undesired, unauthorized software onto a network device. Malware can easily spread from one device to another, making it very difficult to get rid of
  entirely.
• Password Attacks: Any type of attack that involves someone attempting to use a password illegitimately is considered to be a password attack. The hacker may obtain access either by guessing, stealing or cracking a password.
• Social Engineering: These attacks use deception and falsehoods to convince others to give up private information, such as an account password, or to violate security protocols. Social engineering attacks often target people who are
  not tech-savvy, but they may also target technical support staff with false requests for help.

Of course, these are only a few of the many ways that hackers may try to infiltrate network systems, and they will continue to develop new, creative ways to do so. Always pay attention to any unusual activity you happen to notice, and don’t hesitate
to investigate the matter further.

Types of Network Security Solutions

Just as there are many ways to infiltrate a network, there are many different techniques and strategies that IT professionals can use to secure one. Some of the most common types of network security solutions include:

• Antivirus Software: Antivirus software can be installed on all network devices to scan them for malicious programs. It should be updated regularly to fix any issues or vulnerabilities.
• Encryption: Encryption is the process of scrambling data to the point of unintelligibility and providing only authorized parties the key (usually a decryption key or password) to decode it. This way, even if data is intercepted or
  seen by an unauthorized user, they are unable to read it.
• Firewalls: Firewalls are a software program, hardware device or combination of both that blocks unsolicited traffic from entering a network. They can be configured to only block suspicious or unauthorized traffic, while still allowing
  access to legitimate requests.
• Multi-Factor Authentication: Multi-factor authentication is simple: users must provide two separate methods of identification to log into an account (for instance, typing in a password and then typing in a numeric code that was sent
  to another device). Users should present unique credentials from two out of three categories — something you know, something you have and something you are — for multi-factor authentication to be fully effective.
• Network Segmentation: Network segmentation involves breaking down a larger network into various subnetworks or segments. If any of the subnetworks are infiltrated or compromised, the others are left untouched because they exist independently
  of each other.

One security strategy won’t be enough to fully and effectively protect a network. A combination of different techniques will ensure that your network is as secure as possible and will help to meet the unique needs of your organization.

Network Protection Tips

Regardless of your organization’s needs, there are a few general network protection tips and best practices that you should be sure to follow. Below is a very basic overview of some of the most important, but perhaps underestimated, steps IT professionals
should take to ensure network security. A more in-depth guide of all relevant steps and information can be found in the CompTIA Network+ Certification study guide.

Grant Access Sparingly

Always be aware of who has access to your network or servers. After all, not everyone in your organization needs to be able to physically or electronically access everything on your network. Don’t give blanket access to every employee in your organization;
only give out what information is necessary to help reduce the chance of unauthorized access, purposeful or unintentional tampering, or security breaches.

Follow Password Best Practices

It’s a basic principle, but following password best practices is a simple and highly effective way to maintain network security. Many people create passwords that aren’t strong, reuse previous passwords and don’t use unique passwords
for each of their accounts. Encourage all employees to follow password best practices, especially for their work accounts, as it can help keep everyone’s data safe.

Secure Servers and Devices

Physically protect your servers and your devices. Keep them in a safe location, and do not grant general access to this room or area. Be sure the room is locked when it’s not in use and keep an eye on the area when it is unsecured or in use.

Test Your Security

You should never assume that your network is completely secure. Continually test and troubleshoot your network to see what is substandard or to identify any vulnerabilities. Be sure to make fixes and updates as needed.

In addition, if you do not already have a data recovery plan in place, now is the time to create one. Even the best-secured networks are compromised and infiltrated, and though no one wants or necessarily expects that to happen, being prepared for the
worst will make solving the problem significantly easier.

Computer networking is constantly evolving, and what was once considered a network security best practice may soon be a thing of the past. IT professionals need continual education and training to
keep up on the latest security issues and threats, so they can more effectively implement promising network security solutions.

To get started in a computer networking career, check out CompTIA Network+ and the related
training materials.

Network Troubleshooting Applications

In addition to command-line tools, there are also a number of standalone applications that can be used to determine the status of a network and to troubleshoot issues. Some of these applications may be included in the system that you are working with,
while others may need to be installed separately.

• Packet Sniffer: Provides a comprehensive view of a given network. You can use this application to analyze traffic on the network, figure out which ports are open and identify network vulnerabilities.
• Port Scanner: Looks for open ports on the target device and gathers information, including whether the port is open or closed, what services are running on a given port and information about the operating system on that machine.
  This application can be used to figure out which ports are in use and identify points in a network that could be vulnerable to outside attacks.
• Protocol Analyzer: Integrates diagnostic and reporting capabilities to provide a comprehensive view of an organization’s network. You can use analyzers to troubleshoot network problems and detect intrusions into your network.
• Wi-Fi Analyzer: Detects devices and points of interference in a Wi-Fi signal. This tool can help you to troubleshoot issues in network connectivity over a wireless network.
• Bandwidth Speed Tester: Tests the bandwidth and latency of a user’s internet connection. This application is typically accessed through a third-party website and can be used to confirm user reports about slow connections
  or download speeds.

Hardware Tools

Command-line tools and applications are software tools for troubleshooting, but some network problems have hardware causes and solutions.

Here are some hardware tools that can help you diagnose and solve network issues:

• Wire Crimpers: A wire crimper (sometimes called a cable crimper) is a tool that attaches media connectors to the ends of cables. You can use it to make or modify network cables.
• Cable Testers: A cable tester (sometimes called a line tester) is a tool that verifies if a signal is transmitted by a given cable. You can use one to find out whether the cables in your network are functioning properly when
  diagnosing connectivity issues.
• Punch Down Tool: A punch down tool is used in a wiring closet to connect cable wires directly to a patch panel or punch-down block. This tool makes it easier to connect wires than it would be to do it by hand.
• TDR: A time-domain reflectometer (TDR) is a measuring tool that transmits an electrical pulse on a cable and measures the reflected signal. In a functioning cable, the signal does not reflect and is absorbed in the other end.
  An optical time-domain reflectometer (OTDR) is a similar tool, but used for measuring fiber optic cables, which are becoming more common in modern networks.
• Light Meter: Light meters, also known as optical power meters, are devices used to measure the power in an optical signal.
• Tone Generator: A tone generator is a device that sends an electrical signal through one pair of UTP wires. On the other end, a tone locator or tone probe is a device that emits an audible tone when it detects a signal in a
  pair of wires. You can use these tools to verify that signals are passing through the wires in your network. They are often used to confirm phone connectivity.
• Loopback Adapter: A loopback adapter is a virtual or physical tool that can be used for troubleshooting network transmission issues. It can be used by utilizing a special connector that redirects the electrical signal back
  to the transmitting system.
• Multimeter: A multimeter (sometimes called a volt/ohm meter) is an electronic measuring instrument that takes electrical measurements such as voltage, current and resistance. There are hand-held multimeters for fieldwork as
  well as bench-top models for in-house troubleshooting.
• Spectrum Analyzer: A spectrum analyzer is an instrument that displays the variation of a signal strength against the frequency.

How to Develop Your Network Troubleshooting Skills

These are just a few of the steps you can follow and tools that you can use to troubleshoot an issue in your network. For home networks, many issues can be solved relatively simply, by checking connections, making sure that everything is plugged in and
using built-in diagnostic tools.

However, if you want a job working on computer networks, you’ll need to develop your troubleshooting skills to match. Network troubleshooting is an essential skill to have when looking for a job as a network engineer or network administrator, since
companies are primarily concerned with minimizing their network downtime.

If you’re looking for a job, an IT certification related to computer networking is essential as proof of your abilities. Keep in mind that certification exams
test your skills very closely, so make sure to seek out appropriate network training to properly prepare for your exam and test with confidence.

In order to really develop your skills that will land you the job, it’s important to combine training and certifications with real-world network troubleshooting experience. This experience doesn’t have to come from a job – you can
practice your IT skills by tinkering with your own equipment or volunteering with local nonprofits to improve their networks and resolve any issues they’re having.

To get started in a computer networking career, check out CompTIA Network+ and the related
training materials.

Read more about Computer Networks.