Distributed firewall is an mechanisms to enforce a network domain security policy through the use of policy language. Security policy is defined centrally.

1. Nadar saraswathi college of arts &
SCIENCE,THENI.
Department of cs & it
NETWORK AND INTERNET SECURITY
PRESENTED BY..
G.KAVIYA
I-M.SC(IT)
TOPIC:DISTRIBUTED FIREWALL,
LIMITATION OF FIREWALL.

2. DISTRIBUTED FIREWALLS

3. SYNOPSIS
o What is firewall?
o What is distributed firewall?
o Distributed firewall concept.
o Architecture of distributed firewall.
o Components distributed firewall.
o Advantages.
o Distributed firewall implementation.

4. WHAT IS FIREWALL?
Firewall is a device
or instruments
designed to permit
or deny network
transmission based
upon a set of
rules and regulations
which are frequently
used to protect
network from
unauthorized access.

5. WHAT IS DISTRIBUTED FIREWALL?
Distributed firewall is a host resident security software
application. Which protects the network as a whole
against unwanted intrusion.

6. Distributed firewall concepts:
 Distributed firewall is an
mechanisms to enforce a
network domain security
policy through the use of
policy language.
 Security policy is defined
centrally.
 Enforcement of policy is
done by network
endpoints where is the
hackers try to penetrate.
 It filters traffic from both
the internal and internet
network.
 They overcome the single
point of failure concept.

7. ARCHITECTURE OF DISTRIBUTED FIREWALLS:
FOUR CONCEPTS ARE:
 The management center.
 The policy actuator.
 Remote endpoints connectors.
 Log server.

8. DISTRIBUTED FIREWALL EXAMPLE OF
INTRANET:

9. DISTRIBUTED FIREWALL EXAMPLE OF
WEB SERVER:

10. COMPONENTSOFDISTRIBUTEDFIREWALL:
A Distributed firewall is a mechanisms to enforce a
network domain security policy through the use of the
following;
 Policy Language.
 Policy Distributed Scheme .
 Certificate.

11. POLICY LANGUAGE:
 The policy language is used to create policies
for each firewall.
 These policies are collection of rules, Which
guides the firewall for evaluating the network
traffic.

12. POLICY distributed scheme:
 The policy distributed scheme should
guarantee the integrity of the policy during
transfer.
 The policy is consulted before processing the
incoming or outcoming message.
 The distributed of the policy can be different
and varies with the implementation.

13. CERTIFICATE:
There may be the chance of using IP address for the
host identification by the distributed fire walls.
But the mechanism of security is more important.
It is preferred to use certificate to identify hosts.
IPSEC provides cryptographic certificates.
policies are distributed by means of these.

14. ADVANTAGES:
o Provides security for internet and intranet.
o Multiple access points.
o Insiders are no longer trusted.
o Security policy rules are distributed and established
and needed basis.
o End to End can be easily done and filtering packet to
easy.

15. DISTRIBUTED FIREWALL IMPLEMENTATION:
 Language to express policies and resolving request
(key note system).
 Using key note and IPSC allows control of mixed level
policies where authentication mechanism is applied
through public key cryptography.

16. LIMTATION OF
FIREWALL

17. SYNOPSIS
o Firewall Limitations.
o Direct internet traffic.
o Insider’s Intrusion.
o Firewall’s trust on trusted network.

18. FIREWALL LIMITATIONS
A firewall is a crucial component of securing your network and is designed to
address the issues of data integrity or traffic authentication and confidentiality
of your internal network .Your network gains these benefits from a firewall by
receiving all transmitted traffic through the firewall.The importance of including
a firewall in your security strategy is apparent; however, firewall do have
following limitations:
 A firewall cannot prevent users or attackers with modems from dialing in to
or out of the internal network, thus bypassing the firewall and its protection
completely.
 Firewalls cannot enforce your password policy or prevent misuse of
password.
 Firewalls cannot stop internal users from accessing websites with malicious
code, making users education critical.
 Firewalls cannot protect you from poor decisions.
 Firewalls cannot protect you when your security policy is too lax.

19. Direct internet traffic

20. Definition:
 A firewall must be configured very carefully. It effective only if it
is the only entry-exit point of an organization’s network. If,
instead, the firewall is one of the entry-exit points, a user can
bypass the firewall and exchange information with the Internet
via the other entry-exit points. This can open up the possibilities
of attacks on the internal network through those points. The
firewall cannot, obviously, be expected to take care of such
situations.

21. INSIDER’S INTRUSION
Definition:
A firewall system is
designed to the wart
outside attacks. Therefore,
if an inside user attacks the
internet network in
someway; the firewall
cannot prevent such an
attack.

22. FIREWALL’S TRUST ON TRUSTED
NETWORK