Network security is a concept which combines various business models and technologies together to deliver provisions and policies for comprehensive intrusion detection and unauthorized access. The only secured computer is the one with no power and no user. Any other computer can be compromised. Network Security is the most important issue for any organization. This paper includes the different security issues that occur in a private network which can be managed and minimized using software based firewalls like Antivirus based firewall. This paper also includes how we can improve the network security by implementing the same Antivirus based firewall on a Private Cloud using Software as a Service (SaaS) approach for better scalability and improved reliability. Antivirus software on a system does not provide full security as they fail to detect many modern threats and modern virus codes and the increasing complexity are being exploited by malware. This paper brings a new model of end hosts threat detection technique based on threat analysis by antivirus software services as a cloud network service[12]. This paper describes how the whole network infrastructure can be controlled flexibly at administrator and client level.

Firewalls private cloud Antivirus (AVR) infrastructure Software as a Service (SaaS) in- cloud network service.