The IT Manager’s Security Guide

Protect your IT Network with ‘The IT Manager’s Security Guide’. A simple guide to keeping your network secure.


At Exigent Networks security is one of our top priorities. In today’s blog we explore the various threats your IT network might face. From Viruses to Worms and eavesdropping to phishing our IT Manager’s Security Guide is the ideal resource to keep our network safe and secure.


  1. Access – Authorised users are provided the means to communicate with the network
  2. Confidentiality – Information in the network remains private
  3. Authentication – Ensure the users of the network are who they say they are
  4. Integrity – Ensure the message has not been modified in transit
  5. Non‐repudiation – Ensure the user does not refute that he used the network



Interception of communications by an unauthorised party is called eavesdropping.

  • Passive eavesdropping is when the person secretly listens to networked messages.
  • Active eavesdropping is when the intruder listens and inserts something into the communication stream.


Viruses are self‐replication programs that use files to infect and propagate.


There are two main types of worms:

  • Mass mailing worms use email as a means to infect other computers.
  • A network‐aware worm selects a target and infects it


Trojans appear to be benign programs to the user, but will actually have some malicious purpose.


Phishing is an attempt to obtain confidential information by tricking users into disclosing personal data like credit card numbers or online banking credentials.

IP Spoofing Attacks

Spoofing mirrors the address of a trusted computer in order to gain access from an unauthorised computer.

Denial of Service

Denial of Service is an attack when the system cannot return communication to a high volume of requests, and subsequently shuts down.


Cryptographic systems

Cryptography is a useful and widely used tool in security engineering today. It involved the use of codes and ciphers to transform information into unintelligible data.


A firewall is a perimeter defence designed to prevent unauthorized access to or from a private network.

Intrusion Detection Systems

Intrusion Detection Systems (IDS) are software and hardware devices used to detect an attack.

Anti‐Malware Software and scanners

Anti‐Malware tools are used to detect viruses, worms and Trojan horses and cure an infected system.

Secure Socket Layer (SSL)

The Secure Socket Layer (SSL) is a suite of protocols designed to create a secure channel between a web browser and the web server.



Encrypt your data:

Encryption is essential for protecting sensitive data and to help prevent data loss due to theft or equipment loss.

Use digital certificates to sign all of your sites:

Save your certificates to hardware devices such as routers or load balancers and not on the web server as is traditionally done. Obtain your certificates from one of the trusted authorities.

Implement DLP and auditing:

Use data loss prevention and file auditing to monitor, alert, identify, and block the flow of data into and out of your network.

Implement a removable media policy:

Restrict the use of writeable media like USB drives or external hard disks as they facilitate security breaches in your network.

Secure websites against and malware infections:

Use SSL, scan your website daily for malware, set the secure flag for all session cookies, and use SSL certificates with Extended Validation.

Use a spam filter on email servers:

Use a time-tested spam filter to remove unwanted email from entering your users’ inboxes and junk folders. Teach your users how to identify junk mail even if it’s from a trusted source.

Use an endpoint security solution:

Use a multi-layered security solution to prevent malware infections on user devices. Antivirus, personal firewall, and intrusion detection are all part of the total approach to endpoint protection.

Network-based security hardware and software:

Use firewalls, gateway antivirus, intrusion detection devices, honey pots, and monitoring to screen for DoS attacks, virus signatures, unauthorized intrusion, port scans, and other “over the network” attacks and attempts at security breaches.

Maintain security patches:

Be sure that your software and hardware defences stay up to date with new antimalware signatures and the latest patches

Educate your users:

An informed user is a user who behaves more responsibly and takes fewer risks with valuable company data, including email.