Building a Blueprint for Network Security

Ever gone out and then spent the evening wondering whether you remembered to lock all the doors back at home?

If you’re responsible for a corporate network, you’ve probably had a similar feeling — is my network secure, or have I forgotten something that could leave my organization wide open to attack from the first hacker to probe my network for vulnerabilities?

It’s an important question, and one worth spending some time considering. How can you be sure you’ve done everything reasonable to secure your network?

If you’ve just assumed responsibility for a network and time is of the essence, the first thing to do is check the existing patch management policy. According to research from Gartner Group, around 30% of damage to networks stems from organizational failure to implement patches in a timely fashion. If you find unpatched systems, get them in order as quickly as possible.

The same research found that 65% of intrusions stem from misconfigured systems, with only 5% coming from problems that were not previously known. To go back to the house analogy, 95% of security problems are caused by casual walk-in burglars who find you don’t bother to shut all the windows and doors when you go out, while only 5% come from more devious and determined thieves.

At this stage you may want to examine the configuration of every device on your network. But if you’re really keen to get moving, then it’s probably wise to hire some penetration testers to check if there are any serious vulnerabilities in your network that are likely to be found by would-be intruders.

It’s also useful to test the security of your network from the inside — there are a wide range of statistics available that indicate a high proportion of network attacks come from employees. This can be achieved by giving penetration testers a realistic amount of inside knowledge and network access, and then discovering what kind of trouble they can get into.

Page 2: An Overall Security Architecture