This book is a practical guide to building your own firewall. It provides step-by-step explanations of how to design and install a firewall at your site and how to configure Internet services such as electronic mail, FTP, the World Wide Web, and others to work with a firewall. Firewalls are complex, though, and we can't boil everything down to simple rules.
When I rst started using OpenBSD sometime in 1999, it certainly wasn't
because I wanted to write a book about it. All I needed was a stable server
for my home network, something I could congure and forget about. I tried
all obvious suspects: FreeBSD, NetBSD, OpenBSD, and four or ve different
Linux distributions, My choice was OpenBSD, because it installed
without problems, was easy to congure, and did not have the infuriating
problems with NFS that plagued me on Linux at that time.
In an age when our society relies so heavily on electronic communication, the need
for information security is imperative. Given the value and confidential nature of the
information that exists on today’s networks, CIOs are finding that an investment in
security is not only extremely beneficial but also absolutely necessary. Corporations
are realizing the need to create and enforce an information security policy.
The information in this e book for educational and entertainmnent purposes oly. Although every effort has been made to provide accurate, complete, and reliable information, no warranties of any kind are expresses or implied
This module provides students with the knowledge and skills to install and
configure Microsoft® Internet Security and Acceleration (ISA) Server 2000 as a
cache server and as a firewall.
After completing this module, students will be able to:
Install ISA Server on a computer running Microsoft Windows® 2000 Server.
Configure computers as Web proxy, Firewall, or SecureNAT clients for
Perform administrative tasks for maintaining ISA Server.
Check Point Access Control Solution
A Security Gateway at the network boundary inspects and provides access control for all traffic. Traffic that does not pass though the gateway is not controlled. A security administrator is responsible for implementing company security policy. The Security Management Server enables administrators to enforce security policies consistently across multiple gateways. To do this, the administrator defines a company-wide security policy Rule Base using SmartDashboard and installs it to the Security Management Server.
Attackers can infect your computer with malicious software, or malware, in many different ways.
They can take advantage of unsafe user practices and flaws in your computer’s programs (flaws
including vulnerabilities and unsecured services and features) and use social engineering (in
which an attacker convinces someone to perform an action such as opening a malicious email
attachment or following a malicious link). Once your computer is infected, intruders can use the
malware to access your computer without your knowledge to perform unwanted actions.
When using other commercial operating systems, ensure that you fully review operations manuals to
discover if your system has a firewall included and how it is enabled.
There are commercial software firewalls that you can purchase at a reasonable price or free that you can
use with your Windows systems or with other operating systems. Again, internet searches and using
online/trade magazine reviews and references can assist in selecting a good solution.
“The highest-performing people I know are those who have installed the best
tricks in their lives.”—David Allen, productivity guru 1
Contrary to the popular misuse of the term to denote a computer criminal, a
hacker is someone who solves a problem in a clever or non-obvious way. A
lifehacker uses workarounds and shortcuts to overcome everyday difficulties
of the modern worker: an interrupt-driven existence of too much to do and too
many distractions to keep you from doing it.
This paper is the second in a three-part series of white papers, each of which focuses on a functional area of
securing your network. As introduced in the first installment, network security should be implemented throughout
your entire network. Take a layered approach and introduce security at every layer possible. This second
paper will suggest steps to secure your Router, Firewall, and Virtual Private Network (VPN) Concentrators.
NetFilter Checklist Building a NetFilterbased firewall is not difficult. End users interested in setting up their own NetFilter firewall can use the system to be used as the firewall. Install additional network interfaces (minimum number of required interfaces is two)
A Security Gateway at the network boundary inspects and provides access control for all traffic. Traffic that
does not pass though the gateway is not controlled. A security administrator is responsible for implementing company security policy. The Security Management
Server enables administrators to enforce security policies consistently across multiple gateways. To do this,
the administrator defines a company-wide security policy Rule Base using SmartDashboard and installs it to
the Security Management Server.
Packet snooping can be detected in certain instances, but it usually occurs without anyone
knowing. For packet snooping to occur, a device must be inserted between the sending and
receiving machines. This task is more difﬁcult with point-to-point technologies such as
serial line connections, but it can be fairly easy with shared media environments. If hubs or
concentrators are used, it can be relatively easy to insert a new node. However, some
devices are coming out with features that remember MAC addresses and can detect whether
a new node is on the network.
The first step is to install the administration management tools. Agnitum Command Center, the
main managing application is implemented as an MMC snap-in. It lets you manage Outpost
Network Security Client installations over the network and control the other Outpost Network
Security components (Client Configuration Editor to create and configure firewall settings,
Agnitum Update Service, and Agnitum Publisher Service to publish and transfer your firewall
settings to clients). Outpost Network Security does not need to be installed on a server or domain
The ongoing development of the BACnet standard is opening the door for lower cost and
more efficient building control systems that provide expanded services. This report seeks
to address the security implications within the world of BACnet implementations. The
report begins with an overview of BACnet and typical BACnet BCS installations along
with a discussion of the security environment and review of threats to that system. The
report then goes into detail on the threats, and finally possible countermeasures. ...
IPS/HIPS provide for an increased level of protection not available from a static access list or stateful firewall
inspection. IPS and HIPS offer security by sensing abnormalities in traffic communications or protocol, and
packet behaviors that are known to have malicious objectives. Here are some recommendations for installing
and hardening your IPS sensors:
This module provides students with the knowledge and skills that they will need
to design a complex installation of multiple products on a single server. After
completing this module, students will be able to:
Choose a hardware platform.
Determine the Microsoft® Windows® 2000 operating system configuration
for the Web infrastructure servers.
Select the appropriate technology for a highly available solution based on
Microsoft Internet Information Services (IIS).
Design a highly available COM+ (Component Object Model) Environment
by using Microsoft Application Center 2000.
PIX Firewall displays a warning message if the configuration file (stored in Flash memory) is newer than
the PIX Firewall software version currently being loaded. This message warns you of the possibility of
unrecognized commands in the configuration file. For example, if you install version 6.0 software when
the current version is 6.2, the following message appears at startup:
You will see a software installation policy record for the selected package in the right pane of the
MMC console window. The client firewall setup will be installed the next time each client
computer starts up regardless of which user logs onto it if the GPO is linked to the computer.
Note: See the documentation on administering group policies for detailed information on
deploying software applications using a group policy.