Firewalls | Packet Filtering

The most basic feature of a firewall is the packet filter. Firewalls that are only packet filters—also known as stateless inspection firewalls—are essentially routing devices that provide access control functionality for host addresses and communication sessions. Unlike more advanced filters, packet filters are not concerned about the content of packets.

Their access control functionality is governed by a set of directives referred to as a ruleset. Packet filtering capabilities are built [..]

Overview of Firewall Technologies

Firewalls are devices or programs that control the flow of network traffic between networks or hosts that employ differing security postures. While firewalls are often discussed in the context of Internet connectivity, they may also have applicability in other network environments.

For example, many enterprise networks employ firewalls to restrict connectivity to and from the internal networks used to service more sensitive functions, such as personnel or accounting. An organization [..]

IPv6

IPv6 is a new version of IP that is increasingly being deployed. Although IPv6’s internal format and address length differ from those of IPv4, many other features remain the same—and some of these are relevant to firewalls.

For the features that are the same between IPv4 and IPv6, firewalls should work the same. For example, blocking all inbound and outbound traffic that has not been expressly permitted by the firewall policy [..]

Firewalls and Network Architectures

Firewalls are used to separate networks with differing security requirements, such as the Internet and an internal network that houses servers with sensitive data. Organizations should use firewalls wherever their internal networks and systems interface with external networks and systems, and where security requirements vary among their internal networks. This section is intended to help organizations determine where firewalls should be placed, and where other networks and systems should be [..]

Is it a good have 2 firewalls running simultaneously ?

We recommend that you run only one antivirus and one firewall at a time. Having more than one antivirus or firewall active in memory uses additional resources and can result in software conflicts, network and software access problems and false virus alerts. Your best defense against computer viruses and malicious programs is to keep your antivirus virus definitions up to date and update your antivirus and firewall to lasts [..]

Distributed Firewalling

Distributed firewalling is an emerging security technology in firewall deployment that moves security from the perimeter to device endpoints. This is accomplished by placing a firewall in or directly in front of every endpoint and other appropriate devices in the network. The theory of distributed firewalling is that this can ease the burden on the perimeter and internal firewalls, which have traditionally been major chokepoints for network access. As distributed [..]

Firewalls Testing

New firewalls should be tested and evaluated before deployment to ensure that they are working properly. Testing should be completed on a test network without connectivity to the production network. This test network should attempt to replicate the production network as faithfully as possible, including the network topology and network traffic that would travel through the firewall. Aspects of the solution to evaluate include the following:

• Connectivity. Users can establish and [..]

Extranet VPN

Almost every company has a select group of suppliers, vendors and other business partners they do business with. Business interactions between these organisations include communication, collaboration and, in many cases, commercial transactions.

In today’s rapidly changing and highly competitive global economy, speed and cost can determine a company’s success or failure. As the traditional business exchange methods often prove to be slow, paper-based, timeintensive, and expensive, companies are looking to improve [..]

Intranet VPN

Many VPNs, of different companies, can be created on the same shared IP backbone infrastructure of a Service Provider. This is one of the reasons why VPNs are far less expensive for companiesthan full private networks based on a WAN infrastructure.

A complete VPN solution therefore incorporates encrypted tunneling, QoS,security, management, and provisioning capabilities, to create a reliable [..]

Firewall – VPN Environments

Firewall environments are made up of firewall devices and associated systems and applications designed to work together. For example, one site may use a firewall environment composed of a boundary router, a main firewall, and intrusion detection systems connected to the protected network and the network between the router and main firewall.

The latest trend in firewall offerings is to add cryptographic services for firewall to firewall encryption. The encrypted traffic[..]