Uses of free Unix-based Security Tools to Develope Secure Systems – Part 4


“Enumeration can best be defined as the process of counting. From a security standpoint, it’s the process the attacker follows before an attack. The attacker is attempting to count or identify systems and understand their role or purpose.

This may mean the identification of open ports, applications, vulnerable services, DNS or NetBIOS names, and IP addresses before an attack.”

Michael Gregg (2008, p 149)

This means at this stage it’s only a matter of time before the attacker compromises a system on the network.

The main aim of this stage is to find:


Uses of free Unix-based Security Tools to Develope Secure Systems – Part 3


At this stage an attacker would’ve got a list of IP ranges, DNS servers, Mail servers, employee names and phone numbers. All this would be used by attackers to probe our network to see which systems are alive and the services running on them.

There are many tools and techniques available to accomplish this.

Ping sweeps basically a method used to find out which of a range of IP addresses are a live and reachable from the internet.

Fping can be used on large networks, it doesn’t wait for a reply before trying the next IP, it sends many requests in parallel.

root@bt:#fping -a -f ipadd.txt

-a – shows systems that are alive.

-d – resolves hostnames.

-f – read from file.

-h – help.

Nmap is another tool that can be used for ping sweeps.

root@bt:#nmap –sP

There are other methods that can be used if ICMP is blocked but they are not as accurate as Continue reading

Uses of free Unix-based Security Tools to Develope Secure Systems – Part 2


The aim of foot printing is to gather as much information as possible about the organisation and its network. One would ask why would I need to perform such step when I have all the information about my network?

Joel Scambray, Stuart McClure and George Kurtz (2009, page 10), answers this question:

“Foot printing is necessary for one basic reason: it gives you a picture of what the hacker sees. And if you know what the hacker sees, you know what potential security exposures you have in your environment. And when you know what exposures you have, you know how to prevent exploitation.

Hackers are very good at one thing: getting inside your head, and you don’t even know it. They are systematic and methodical in gathering all pieces of information related to the technologies used in your environment. Without a sound methodology for performing this type of reconnaissance yourself, you are likely to miss key pieces of information related to a specific technology or organization—but trust me, the hacker won’t.”


“Foot printing is one of the most important steps and it must be performed accurately and in a controlled fashion.” Continue reading

Uses of free Unix-based Security Tools to Develope Secure Systems – Part 1


In today’s world it is very rare to find a business or an organisation that is not reliant on a computer network of some sort, whether it is a hospital, a school, large bookstore, small shop or even a home business. This sets a challenge for IT professionals around the world, especially with the increased number of network attacks that are happening every day. The challenge is how to keep these networks secure?

What is network security?

Network security to IT professionals doesn’t mean that a network is 100% secure because that is impossible unless you completely disconnect your network from the outside world and even that doesn’t protect the network from internal attacks or the physical theft of the computer and the data inside it. The only way to have 100% security is to power off all computers and for businesses these days that isn’t an effective decision. Continue reading


By clicking on the networking menu above you’ll find a page that aims at providing tutorials on various networking topics. At the moment I’m trying to provide tutorials that help those preparing for any of the certifications such as CompTIA Network + to reinforce the materials they’ve studied. The topics I’m planning to discuss are as follows:

  1. Network +
  2. Security +
  3. CCNA Networking
  4. CCNA Security

After finishing with these I’ll then focus on the main topic of the site, which is Information Security and can be tracked from this home page (front main page of the site). Some of the topics I’m planning on discussing here are:

  1. Information Security principles (cryptography)
  2. Network Security
  3. Systems Security
  4. Applications Security
  5. Intrusion Detection
  6. PenTesting

So please be patient with me as amongst other things (looking for employment, family life, etc) it took me a while to get familiar with the interface to set this site up because it is my first site or blog.




Information systems have become very important in every business not only that, today you can hardly find a business, organisation or even home businesses that doesn’t have a computer network of some sort. These businesses have become very dependent on these systems for their daily day-to-day operations. Thus the effectiveness of organisation’s business performance has become greatly dependant on the availability, reliability and security of these computers and the networks they’re connected to.

Continue reading