Sunday, 12 November 2006

Securing the Network: 1

This next series of posts is entitled:

Securing The Network
A Post on Corporate Security Issues for the Non Technical

This post covers:
                What is a Hacker
                The Security Triad
                The Laws of Security

Security can be likened to Insurance. Most people and organisations never really consider it worthwhile until the worst happens. Today we live in an age where computer and network security has to be at the top of the CIO’s agenda. There is too much at stake for security to be an afterthought.

Unfortunately security and convenience/practicality are at opposite ends of the user experience. As such security will always be a compromise. To give a contemporary example: It is extremely easy to stop terrorists getting on commercial flights. Use airplanes for cargo only. Problem Solved. This however is not a practical solution and so a compromise between security and practicality is necessary.

This document looks at the computer and network security that is needed within the modern enterprise and explains in layman’s terms the policies, procedures and settings that are essential to ensure that if security is going to be compromised then somebody is going to have to work hard to do it.

This is not a comprehensive security document and it does not cover every eventuality. The suggestions it makes however, if followed, are likely to lead to more comprehensive security than what your competitors and most other companies have.

After all, you don’t always have to be able to run fast, as long as you run faster than the other person when you are both being chased by a bear …

What is a Hacker ?
You will see references to the word ‘Hacker’ throughout this document. I have used the word ‘Hacker’ as it should be used, not as it is often used in modern literature or in Hollywood films.

A Hacker is someone who likes to know, in depth, about a subject. Someone who is willing to study and tinker until they gain mastery of their craft. Generally accepted to be gifted Programmers or System Administrators they can I believe be categorised by their belief that if the knowledge is worth pursuing they won’t necessarily let laws or restrictions stop them. The average Hackers attitude is probably a bit ‘Grey’ as opposed to either ‘Black’ or ‘White’.

A Hacker , like anybody else can have either good or bad intentions, and be capable of either good, bad or indifferent acts. In this document you should understand the type of Hacker I am describing by the context of the paragraph in which they are mentioned.

The Security Triad
The three cornerstones of information security are:


Confidentiality is concerned with information being accessible to only the intended recipient. This may be documents, database information, emails or even instant messages.

Integrity is concerned with the fact that for information to be trusted we must know that it has only been modified by those who are authorised to do so. In addition the data must be 100% accurate.

Availability is making sure the information is available to the right person(s) when it is needed. Factors that affect this delivery of information such as incorrect permission settings or denial of service attacks are examples of how availability may be compromised.

TECH NOTE: Denial of Service Attack: This is when several hundreds or thousands of computers are commandeered by a Hacker and all set to send requests to a targeted website simultaneously. This can often cause the targeted website to crash or become otherwise unusable.

The concept of security in the enterprise involves considering and balancing these three concepts, every step of the way.

The Laws of Security
Client side security does not work.
You cannot securely exchange encryption keys without a shared piece of information.
Malicious code cannot be 100% protected against.
Any malicious code can be completely altered to bypass signature detection.
Firewalls cannot protect you 100% from attack.
Any Intrusion Detection System (IDS) can be evaded.
Secret cryptographic algorithms are not secure.
If you don’t have a key, you don’t have encryption, you have encoding.
Passwords cannot be securely stored on the client, without password protection.
For a system to be considered secure, it must undergo an independent security audit.
Security through obscurity does not work.

Source: INFOSEC Career Hacking, Syngress 2005.

"I want freedom for the full expression of my personality." - Mahatma Gandhi

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