Practical Connection

A firewall enforces your organization’s network security policy. Specifically, a firewall enforces the network traffic access control security policy. A firewall is the physical embodiment of the security policy (Stewart, J. M). A firewall stands as a sentry, as a front guard, as a defense against all attacks and attempts at system compromise(Stewart, J. M). The good news is that many firewalls are well hardened against all known-to-date attacks. These firewalls can withstand the blitzkrieg of the attacks without faltering (Stewart, J. M). A firewall protects the network against the substantial asset damage that external attacks can cause (Stewart, J. M).

Your personal computer needs a firewall. Your home network needs firewalls. Your company network needs firewalls. Every network needs firewalls. They are a fundamental of network communication.(Stewart, J. M). Computers and networks are online all the time—and exposed to attacks. A drawbridge is easy to cross if it’s always down. When a system is always connected, it can be the focus of a concerted attempt to discover its vulnerabilities and breach its security (Stewart, J. M). Most systems are detected, scanned, and probed within minutes of obtaining a public IP address. It is technical suicide to connect your system to the Internet before installing a firewall, as well as installing the latest vendor patches for the hardware, OS, and installed applications (Stewart, J. M). A hardware firewall can protect a single host or a network of hosts, while a software firewall can protect only a single host. host firewall also protects the network from a user in general. A user is the most risky element in a network infrastructure. Firewalls protect against Internet threats, protect against internal network threats, protect resources generally, and protect against the risk of users. These capabilities alone might make installing a firewall on every host and on every segment seem like the obvious follow through(Stewart, J. M).

A zone of risk is any segment, subnet, network, or collection of networks that represents a certain level of risk. The zones of risk is zones of trust. Highly trusted zones naturally require less security, while zones of low trust require more protection. Most networks have two to four zones of risk. These include the private network, DMZ, extranet, and the Internet. The private network zone has the lowest risk and is the zone of the highest trust. The Internet zone has the highest risk and is the zone with the least trust. A DMZ has less risk than the Internet, but is not as trusted as the private network. Your organization’s written security policy should define where these zones exist and dictate the security requirements for each zone. Such requirements would include traffic management, use of firewalls, use of VPNs to cross the zone divisions, hardening of systems, malicious code scanning, and so on

A firewall is an essential part of network security. However, it’s not the whole of network security. A firewall is primarily for network traffic filtering. It’s not an authentication system. A firewall is not a remote access server. Instead, the endpoint is a remote access server (RAS) or network access server (NAS). A firewall may function before or after the RAS/NAS to filter remote access traffic. However, that doesn’t mean the firewall is the RAS/NAS itself. since the original header is in plaintext form. However, a firewall cannot filter the original header of traffic using tunnel mode encryption, since the only plaintext component is a temporary tunnel header that only includes information about the endpoints of the tunnel. A firewall is also not a malicious code scanner.A firewall is also not an intrusion detection system. A common misconception is that firewalls protect against insider attacks. They cannot. Another thing firewalls can’t do is protect against social engineering. Social engineering is the category of attacks that focus on the personnel of an organization.