This document defines and describes different types of firewalls. It begins by defining a firewall as a hardware or software network security system that controls incoming and outgoing network traffic using rules. It notes that the first firewall was invented by William Cheswick, Steven Bellovin, and others. The document then describes three main types of firewalls - packet filtering, application proxy, and hybrid - and provides details on their workings, advantages, and disadvantages. It concludes by stating that while firewalls help protect systems, they are not fully secure on their own.

3.  WHAT IS FIREWALL (DEFINATION).
 INVENTOR OF FIREWALL.
HARDWARE AND SOFTWARE FIREWALL.
TYPES OF FIREWALL.
WORKING OF FIREWALL.
CONCLUSION.

4. Firewall is a network security,either hardware or
software based,that uses rulers to control incoming and
outgoing network traffic.
Firewall acts as a barrier between a trusted and
untrusted networks. Firewall controls access to the
resources of network through a positive control model

5. FIRST FIREWALL WAS INVENTED BY
WILLIAM BILL CHESWICK STEVEN M BELLOVIN

6. It is a in-built program

7. It is a device placed in between your network and
untrusted internet server.

8. 1. Packet filtering firewall.
2. Application proxy firewall.
3. Hybrid firewall.

9. A packet filtering firewall applies a set of rules to each
incoming and outgoing IP packet and then forward or
discards the packet
PACKET FILTERING FIREWALL

10. ADVANTAGES
 Low in price.
Best suited for small networks.
DIS-ADVANTAGES
It only works on network layer.
They cannot protect application-layer attacks.

11. In such a firewall remote host or network can interact
only with proxy server, proxy server is responsible for
hiding the details of the internal network i.e. intranet.
APPLICATION PROXY FIREWALL

12. ADVANTAGES
More secure than packet filtering firewall.
Easy to audit the incoming traffic data.
DIS-ADVANTAGES
They supports very small numbers of application.
They sometimes requires special client software.

13. This firewall act in combination of packet firewall and
application firewall. In this both firewall are in series, if
they are in parallel terms so only 1 of them will work.
HYBRID FIREWALL

14. ADVANTAGES
Provides best internet security.
It provides high speed data transmission.
Dis-advantages
As this is a high secured firewall it allows less program
to run.

15. As in previous we have read that what is firewall, its
only acts between computer and internet server.

16. BETTER THAN NOTHING
BUT NOT GOOD ENOUGH
A firewall will help you to protect your system
from intruder or hackers to enter your system,
but it is not fully secured.
Firewall will stop you by
accessing web-sites but its up to you whether to
decline it or to access it.

17. THANK
YOU