28-06-2010, 10:26 PM
Network Security
Presented By:
-D.Pavan Kumar
3/3 M.C.A I Semester
Introduction:
¢ Technologies such as Internet, e-mail, Business-to-Business are forcing enterprises to open up their IT doors to the rest of the world in order to remain competitive.
¢ With the expansion of the space to which data is exposed it is necessary to protect it from the attacks. Our E-mails are the most insecure data in the world.
¢ The facts produced show how insecure is the data.
¢ This urges the necessity for network security
What is Network?
¢ A ``network'' has been defined as ``any set of interlinking lines resembling a net, a network of roads || an interconnected system, a network of alliances.''
¢ The protection of networks and their services from unauthorized modifications, destructions.
¢ It provides assurance the network performs it critical functions correctly and these are no harmful side effects.
What is security?
¢ The process of security consists policy, procedure and training. It contains preventive control measures.
¢ The purpose of security policies is to establish the requirements on which you build the rest of the security process.
¢ The first step to understanding security is to know what the potential risks are, or more specifically, to determine the type and level of security risk. Security risks are unique.
Internet:
¢ The Internet is the world's largest network of networks. But not a network of hosts.
¢ The Internet resources are shared by connecting to the Internet backbone but not really Internet
Internet-connected Network
Origin of firewall:
¢ A firewall is a system designed to protect our data and network from such attacks.
¢ A firewall is a set of Hardware components, a router, a host computer or some combination of routers
¢ Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets.
Building a Firewall:
¢ A Firewall is installed at the point where the network connects to the Internet.
¢ Building a firewall to protect the data resource and reputation.
¢ There are three major characteristics that need to be protected: Security, Integrity and Availability.
¢
Firewall
Mechanism:
A Firewall normally includes mechanisms for protection at
Network Layer: IP packets are sanitized (only packets with valid external addresses allowed) and routed according to predefined rules.
Transport Layer: Access to TCP and UDP ports can be guaranteed or blocked depending on the IP address of sender and receiver. This allows access control for many TCP services.
Types of Firewalls:
 Application Gateways
 Hybrid Systems
 Packet filters
¢ Application gateway
¢ Circuit-level gateway
¢ Proxy server
Application Gateways:
The Architecture of Application Gateways
Application Gateways
Packet filters:
The Architecture of Packet filters
Packet filters
Advantages:
¢ Firewalls protect a server programs by allowing access only to no ones.
¢ A firewall improves network security and reduces server risks.
¢ Firewalls protect against administrator errors.
Conclusion:
The key for building a secure network is to define what security means to your organization. Once that has been defined, everything that goes on with the network can be evaluated with respect to that policy. The increasing threats are forcing the experts to construct a well-defined perimeter that spies the traffic coming in and going out of the system.
Hence I conclude that we have to pay much attention not only for developing software and also for its security.
