Firewall 
a firewall is a system designed to prevent unauthorized access to or from a private network. You can implement a firewall in either hardware or software form, or a combination of both. Firewalls prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet (i.e., the local network to which you are connected) must pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.

Benefits of a firewall

Firewalls protect private local area networks from hostile intrusion from the Internet. Consequently, many LANs are now connected to the Internet where Internet connectivity would otherwise have been too great a risk.

Firewalls allow network administrators to offer access to specific types of Internet services to selected LAN users. This selectivity is an essential part of any information management program, and involves not only protecting private information assets, but also knowing who has access to what. Privileges can be granted according to job description and need rather than on an all-or-nothing basis.

Several types of firewalls

  • Packet filtering: The system examines each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet filtering is fairly effective and transparent to users, but it is difficult to configure. In addition, it is susceptible to IP spoofing.
  • Circuit-level gateway implementation: This process applies security mechanisms when a TCP or UDP connection is established. Once the connection has been made, packets can flow between the hosts without further checking.
  • Acting as a proxy server: A proxy server is a type of gateway that hides the true network address of the computer(s) connecting through it. A proxy server connects to the Internet, makes the requests for pages, connections to servers, etc., and receives the data on behalf of the computer(s) behind it. The firewall capabilities lie in the fact that a proxy can be configured to allow only certain types of traffic to pass (e.g., HTTP files, or web pages). A proxy server has the potential drawback of slowing network performance, since it has to actively analyze and manipulate traffic passing through it.
  • Web application firewall: A web application firewall is a hardware appliance, server plugin, or some other software filter that applies a set of rules to a HTTP conversation. Such rules are generally customized to the application so that many attacks can be identified and blocked.

Types of firewalls

Basically two types of firewalls:

  • Software-based firewalls   : these are often run as additional programs on computers that are used for other things. They are often known as personal firewalls which can be updates on personal computers.
  • Hardware-based firewalls   : Hardware based firewalls run on a dedicated computer (or appliance). Often, these offer a better performance than software firewalls, but they are also more expensive.

Difference between Hardware & Software Firewall:

Software Firewall

  • A Software firewall is not physical device; it is only software which is generally installed on your computer used for protecting it.
  • Software firewalls are best suited for protecting computers from Trojan programs or e-mail worms.
  • If Software firewall is built-in mail server could attempt to send mail on the valid Simple Mail Transfer Protocol (SMTP), port (25), which would probably pass through the hardware firewall because of its trusted origin.
  • Some software firewalls are flexible enough to incorporate your existing anti-software into its firewall program.
  • Some software firewalls also include parental controls to manage what kinds of websites your children visit.
  • Special packages will also allow you to block photos and specific text content that you do not want your children to view.
  • Some top software firewall packages also include anti-spam, anti-virus, even anti-popup ad software.
  • Software firewalls are best suited for the home user who wants easy customization.
  • One of the drawbacks of software firewalls is that they can only protect the machine they’re installed on, so if you have multiple computers (which many small offices do), you need to buy, install, and configure a software firewall separately on each machine. This can get expensive and can be difficult to manage if you have a lot of computers.

Hardware firewall:

  • A Hardware firewall is a physical device with physical elements like RAM, flash, processor, Ethernet ports.
  • Hardware firewalls are best suited to businesses and large networks.
  • Hardware firewalls are also quite costlier than normal software firewall.
  • Hardware firewall provides strong protection from most forms of attack.
  • A hardware firewall employs packet filtering, which examines the header of a packet to determine its source and destination addresses. This information is compared to a set of predefined and/or user-created rules that determine whether the packet is to be forwarded or dropped. It includes a more advanced technique called Tasteful Packet Inspection, which looks at additional characteristics such as a packet’s actual origin (i.e. did it come from the Internet or from the local network) and whether incoming traffic is a response to existing outgoing connections, like a request for a Web page.
  • Hardware firewall supports VPN which is most secure way of accessing your local network from remote site. People who are allowed in VPN tunnel only they can access your ftp server …etc.
  • In Cisco ASA hardware firewall have feature of failover, which can be used for redundancy. But it is disruptive kind of communication.
  • The ASAs are fully capable of offering anti-spam, anti-phishing, anti-spyware, and anti-virus scanning within your internal network with an added module.

Free Software Firewall 

1. Comodo Firewall

Web link: –   http://www.comodo.com/home/internet-security/firewall.php

2. Online Armor

Web link: – http://www.online-armor.com/

3. Zone Alarm

Web link: – http://www.zonealarm.com/

Commercial Firewall hardware Tools

(1)

Web link: – http://www.cisco.com/en/US/hmpgs/index.html

(2)

Web link: – http://www.sonicwall.com/in/en/

(3)

 Web link: – http://www.juniper.net/us/en/ 

What is VPN?
VPN stands for virtual private network. A VPN keeps your wireless communications safe by creating a secure “tunnel,” though which your encrypted data travels. These tunnels cannot be entered by data that is not properly encrypted. Not only is data encrypted when you use a VPN, but the originating and receiving network addresses are also encrypted. This adds an extra layer of security.

 Benefits of VPN

  • Provides a layer of security and anonymity.
  • Prevents local ISP from regulating your connection.
  • Prevents harassment from people tracking you by your IP address.
  • Safe/encrypted connection between your computer and the Internet.
  • Access blocked sites like facebook.com or hulu.com and bypass proxy and content filters.
  • Internet Service Provider won’t know you are using it.
  • Your office or school won’t know you are using it either!
  • Bypass Skype/MSN blocks.
  • Skype sound quality may improve with a VPN connection.
  • Visit all blocked/censored websites.

 Most Famous Free VPN:

1. Ultra VPN

Ultra VPN provides a free Open VPN with the standard off the shelf Open source configuration. Ultra VPN has a tiny network of servers (France & USA) with no server switching.

 Web Link: – https://www.ultravpn.fr/

2. GPASS VPN 

Features:

  • Hide your IP address during web surfing
  • Encrypt your web communication
  • Bypass network censorship
  • Provide encryption for web surfing when using insecure wireless network
  • No software installation. Just come to our web site, and safely surf other websites
  • Free surfing might be limited by daily traffic volume.

3. PacketixVPN

All data transmissions are routed over a secure gateway server and encrypted by SSL. Regardless whether over a wireless LAN, where anybody could intercept the traffic, or over a public Internet access service, you with encryption achieve maximum security against eavesdropping.

Web link: – http://www.packetix.net/en/

4. Hotspot Shield

About Hotspot Shield

  • Secure your web session, data, online shopping, and personal information online with HTTPS encryption.
  • Protect yourself from identity theft online.
  • Hide your IP address for your privacy online.
  • Access all content privately without censorship; bypass firewalls.
  • Protect yourself from snoopers at Wi-Fi hotspots, hotels, airports, corporate offices.

Web Link: – http://www.hotspotshield.com/?lg=en

5. MY US VPN

 Benefits of VPN Service

  • Bypass all blocked web sites, such as adult, poker, sensitive sites!
  • Unrestricted access to the Internet in China, Middle East. eg. UAE, Kuwait, Qatar, Bahrain Oman and so on
  • Unblock all VOIP Applications include Skype
  • Security for Hotspot Wireless Access Users
  • Anonymizes you at work or at school even behind restrictive firewalls!
  • Protection against your ISP, so your ISP can not spy you

Web link: –   http://www.myusvpn.com/

6. Log Me in Hamachi

Features:

  • No hardware required – A quick, simple and easy-to-use VPN that just works
  • Secure communications – Encrypted tunneling across public and private networks
  • Flexible networking – Combines the ease of an SSL VPN with the connectivity of an IP-sec VPN
  • Web-based management – Deploy to anyone, manage from anywhere, access anytime
  • Free for non-commercial usage – Absolutely free for non-commercial use

Web Link: – https://secure.logmein.com/products/hamachi/download.aspx

7. Cyber Ghost PVN

Features:

  • To protect your privacy on the Internet and hinder site operators from tracking you down and clearly identifying you.
  • To get access to uncensored websites outside your country, outside your office or outside your school resp. your university network.
  • To get access to blocked websites or blocked content by circumventing geo, IP or other blockades. Cyber Ghost let you surf as an American, a German, a Dutch … wherever you are.
  • To guard a public Internet connection (WLANs, Hot Spots), so you can make payments or transactions without being spied on.
  • To investigate unbothered as a journalist, an activist or as a police officer.
  • To keep private affairs most private on adult or dating websites or highly delicate situations.
  • Cyber Ghost is Privacy Proofed: Anonymous registration, separated payment process, prepaid & cash payments available, more than contented 1.000.000 users, free choice of servers, more than 70 servers throughout Europe and the USA.

Web link: – http://cyberghostvpn.com/

8. Security KISS

Security KISS Tunnel is a Virtual Private Network (VPN) implementation based on Open VPN, PPTP and L2TP.

It creates a VPN between your laptop and our security gateway what prevents third parties from viewing your web browsing activities, instant messages, downloads, credit card information or anything else you send over the network. Our servers represent you on the Internet and your real IP address is hidden.

Web Link: – http://www.securitykiss.com/index.php

9. PROXPN VPN

 ProXPN Features

  • Provides a fast, reliable, and free VPN encryption
  • Allows you to select an IP from the USA, UK, Netherlands, or Singapore
  • Secures all types of connections from DSL and cable to 3G
  • Gives you 100% private access to the internet
  • Works on all platforms, incl. Windows, Mac OS, iPhone

Web link: – http://proxpn.com/#features

10. EXPat Shield PVN

Features:

  • Get a UK IP address.
  • Secure your web session, data, online shopping, and personal information online with HTTPS encryption.
  • Protect yourself from identity theft online.
  • Hide your IP address for your privacy online.
  • Access all content privately without censorship; bypass firewalls.
  • Protect yourself from snoopers at Wi-Fi hotspots, hotels, airports, corporate offices.

Web Link: – http://expatshield.com/