Скачать или смотреть Network Security Services - 6 : Physical Security

The first type of security we are going to discuss is physical security. One of the first questions a network manager must answer is, "Who should have access to the network devices?" These are the switches and other boxes that make up the backbone of a network, and are essential to keep the network up and running. So, it is very important to make sure that no one can tamper with these devices. Sometimes network security is like a scene from Mission Impossible... while other times it simply involves locking the network switches in a closet.

These protection methods are called physical security. The first level of protection is always physical protection. If you don't want to allow general access to a device, then lock it up. As we mentioned, this could just be behind a locked door in a closet, or, for more important devices, it might be in a controlled-access location protected by alarms and armed guards.

The next level of physical protection involves password-controlled access. Passwords are very important, because even though individuals may be permitted physical access to controlled rooms, they may not be allowed access to specific devices. Password-controlled access to devices ensures that only people who have authorization to use a device can do so - without the correct password, you can't use the device. However, it's important to remember that password protection methods are only as secure as the password and the ability of the password-holder to keep it secret.

Let's use this class as an example. Most of you use some kind of a password for computers, or combinations for a lock, or even a PIN number for ATM machines. Now think about what password you chose. Is it your name, your dog's name, or maybe your birthday? Many people use personal information for their passwords so they will be easy to remember. But because of this, someone who learns about you may be able to figure out your password. Even worse, many people write down passwords and tape them to the underside of their desk or some other convenient place.

The last form of physical protection we're going to discuss is secure switch access. This is the ability to control who can communicate remotely with the switch. The switch is part of the network, so obviously lots of communication will go through the switch.

However, the ability to control who can communicate to the switch is of great concern. It is important to limit who is allowed to configure switches remotely. This can be controlled by only allowing specific types of communication protocols to access the switch and by using passwords across the network to gain access to the switch.

Security monitoring systems are also helpful for keeping track of who gains access to the systems. This way, only the people that should have access to the equipment can get to it.