Security of internet-connected computer networks

The security of computer networks connected to the internet is an important, vital and hotly contested real-world issue. Once the computer networks get connected to the internet, the number of attacks, their strength and intensity grow exponentially. All the attacks then exploit breaches in the network security. In this paper some of the passive and active attacks against the computer networks are presented. The anatomy of the attack is presented showing the phases and the techniques for penetrating into the computer networks – with the purpose to stress and highlight the several dangers faced by the network manager and the utmost necessity of setting a proper corporate network security policy in place. The detection of an attack is a difficult task because the detection technology is still in its infancy and has yet to mature, also once the attack is detected, the attacker in most cases still remains unknown. After the detection of the attack, the analyst needs some time to establish the actual nature of the attack.