World is Welcome To The World of Linux

Journey into the world of linux

Menu
  • About
  • Welcome
Menu

Firewall: Some Basic Ideas

Posted on June 24, 2010 by Ganesh Sharma

If you're new here, you may want to subscribe to my RSS feed. Thanks for visiting!

Firewall is an important and extensive tool for IT security. Writing about firewalls in depth is one of my targets for this blog on IT security. So, to set the ball rolling I’ll start with the basics of firewalls . For today I’ll start the discucssion with firewall basics.

The important part of firewall basics are, so I’ll answer the four basic questions:

  1. What is A Firewall
  2. What is The Need of Firewalls.
  3. What Are Basic Firewall Technologies.
  4. What Are Firewall Capabilities.
  5. What Are Firewall Limitations.

What is A Firewall

A firewall is a protection layer between your server on internet and rest of the internet world. This way it helps to protect your server from external attacks from internet. It also helps to avoid unnecessary traffic to your server on internet.

What is The Need of Firewalls

The growth of internet is increasing the security risks as well. The time comes when you have to connect your server to the internet for live services like email, webservices and several others. At this time::

  1. People should access only specific services at your server on internet. You want to block rest of the traffic to your server.
  2. You want to protect your server and hence network from external threats like hackers.
  3. You want to block internal users to access only specific services outside of your network.
  4. You want to restrict the type of information the users can access from internet.
  5. You want to protect unauthorized users to access information inside your network.

What Are Basic Firewall Technologies

There are several firewall technologies out there. The type of services are:

  1. Packet filtering The one of the most basic types of firewall technologies. This helps to filter the type of traffic which can pass through the firewall.
  2. Application Gateway/ProxyThe application gateway or application proxy is a software which runs on a firewall and intercepts the traffic for a particular application. It acts as a middleman. The internal user will connect to the application gateway and application gateway connects the user to the requested server. Similarly external user connects to the application gateway and the gateway connects the user to some server inside you network. This way certain features of the application can be allowed or disallowed as per your security policy.
  3. Other TechnologiesDMZ(Demiliterized zones), secrificial hosts, hardware firewalls, software firewalls and so on. In later articles I’ll be discussing each one in quite detail.

What Are Firewall Capabilities

The firewalls have various capabilities and can act as swiss army knife for you if you know the nitty-gritty of firewalls.

The capabilities are discussed as below:

  1. It keeps internal network and servers safe from outer attacks. The information is hidden from outside network.
  2. It provides safety from insecure protocols.
  3. It provides log files as audit trails for whatever happened in past since the firewall was implemented. Specifically break-in attempts can be useful.
  4. It can provide the single point of contact from security point of view.
  5. It can provide Network Address Translation capability which means when a user access any service outside your network, their original IP address is not revealed to the outside world, instead your network’s external IP is revealed. So the process becomes transparent.

What Are Firewall Limitations

Along with capabilities, firewall has limitations too. The firewall limitations are discussed as below:

  1. No protection from internal hackers. The hackers inside your network can access various areas of your IT infrastructure. So, for the security in those areas, firewall won’t do anything.
  2. The viruses are controllable upto some extent, but lot of viruses pass through un-noticed.
  3. Just like virus traffic, trojans also pass through un-noticed. So, internal host level security is required to fight with those attacks.
  4. No protection from physical outages or social engineering attacks.
  5. Using a firewall is not a game for the poor players. You need to be knowledgeable about all these technologies to secure your network.

In the days to come, I am going to discuss firewalls in detail. Keep visiting and stay informed. Remember to bookmark this page and also subscribe to our newsletter for keeping in touch with IT security.

1 thought on “Firewall: Some Basic Ideas”

  1. Pingback: Desired Security Policy For Firewall Implementation | World of Security!!!

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Recent Posts

  • Date Command Tutorial(Video)
  • grep Command Tutorial – 1(Video)
  • Introduction To ls Command(Video)
  • Chapter 3
  • Set Position Of Poll Module Into Joomla

Recent Comments

  • Kansas City Trailer Proz on Physical Volume In AIX – A Primer
  • Create volume group in AIX | myunixsheet on How To Create Volume Group
  • Restore of AIX backup on other Unix system - TecHub on What is mksysb And What Are Its Components
  • Firewall Unleashed - InfoSec Institute on Packet Filtering Firewall: An Introduction
  • Manwendra on Proxy Firewall and Gateway Firewall: Introduction

Archives

  • January 2019
  • June 2010
  • May 2010
  • February 2010
  • May 2009
  • April 2009
  • March 2009
  • February 2009
  • January 2009
  • December 2008
  • November 2008

Categories

  • 30 Days To Joomla WebSite Setup
  • A Journey To The World of Linux System Administration
  • Aix
  • Backups
  • Books
  • Firewalls
  • Introduction
  • Joomla
  • Joomla Backup
  • Joomla Web Technology
  • Linux
  • LPAR and Virtualization
  • LVM
  • Pluggable Authentication Modules
  • section navigator pro
  • Security
  • Security Knowledge Base
  • Tips and Tricks
  • Uncategorized
  • World is Welcome Products

Meta

  • Log in
  • Entries RSS
  • Comments RSS
  • WordPress.org
©2023 World is Welcome To The World of Linux | WordPress Theme by SuperbThemes