NETWORK SECURITY

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OUTLINESNetwork & Network SecurityNeed of Network SecurityMethods of Network SecurityFirewall Firewall’s Works Firewall’s ImportanceCryptographyCryptography’s WorkCryptography’s ImportanceRSA AlgorithmRSA Algorithm’s WorkRSA Algorithm’s ImportanceImportance of Network SecurityMaintenance of Network Security

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Network & Network SecurityNetwork:- A network is a group of

two or more computer systems linked together. 

Network security :- Network security consists of the provisions and policies adopted by a network administrator to prevent and monitor unauthorized access, misuse, modification, or denial of a computer network and network-accessible resources

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Need Of Network SecurityThe network needs security against attackers and hackers.

Network Security includes two basic securities. The first is the security of data information i.e. to protect the information from unauthorized access and loss. And the second is computer security i.e. to protect data and to thwart hackers. Here network security not only means security in a single network rather in any network or network of networks.Now our need of network security has broken into two needs. One is the need of information security and other is the need of computer security.On internet or any network of an organization, thousands of important informations are exchanged daily. 

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Methods Of Network Security

Firewall

RSA Algorithm

Cryptography

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Firewall A technological barrier designed to prevent

unauthorized or unwanted communications between computer networks or hosts.

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Firewall’s Works •  Firewall acts like filter or you can

say blocker in technical term which separate or blocks the unwanted information coming from the internet to enter the computers. 

By installing Firewall you can check the working of your employer and you can check the opening of the sites and exchange of information

Firewalls have different methods to control the incoming data packets:-

1. Packet filtering2. Stateful inspection3. Proxy service

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Firewall ImportanceWhenever networking traffic is passed through

the firewall it will decide exactly what to do.We can set the firewall up with a number of rules

to block traffic from certain sources.A basic firewall will only handle incoming

software but the best quality firewalls will also screen outgoing connections as well as incoming connections.

The normal use for firewalls is to protect your computer from public networks such as the internet. Large companies will also need firewalls and  antivirus  applications and these can be hardware utilities instead of software tools.

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CryptographyCryptography is one of the

critical blocks, not only for Network Security, but also for all other areas of Information security, Cyber Security, OS Security, File System Security, Data Base Security, Web Security, Language Level security, Application level security, Wireless Security and Communications Security.

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Cryptography ‘s Work

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Cryptography’s ImportanceSome of the most Modern method of

communicationare inherently insecure.• The internet is very insecure :-1. Traffic passes through central hubs.2. Like a giant party line.• Ethernet networks liable to having sniffers.• Cable modems pass through other people’s

home.

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RSA AlgorithmRSA is an algorithm for 

public-key cryptography that is based on the presumed difficulty of factoring large integers, the factoring problem. RSA stands for Ron Rivest, Adi Shamir and Leonard Adleman, who first publicly described it in 1977.

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RSA Algorithm ‘s Works

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RSA Algorithm ImportanceA cryptographically strong random number generator, which has been

properly seeded with adequate entropy, must be used to generate the primes p and q. An analysis comparing millions of public keys gathered from the Internet was recently carried out by Lenstra, Hughes, Augier, Bos, Kleinjung, and Wachter. They were able to factor 0.2% of the keys using only Euclid's algorithm.[15][16] They exploited a weakness unique to cryptosystems based on integer factorization. If n = pq is one public key and n' = p'q' is another, then if by chance p = p', then a simple computation of gcd(n,n' ) = p factors both n and n', totally compromising both keys. Lenstra et al. note that this problem can be minimized by using a strong random seed of bit-length twice the intended security level, or by employing a deterministic function to choose q given p, instead of choosing p and q independently. Nadia Heninger was part of a group that did a similar experiment. They used an idea of Daniel J. Bernstein to compute the GCD of each RSA key n against the product of all the other keys n' they had found (a 729 million digit number), instead of computing each gcd(n,n') separately, thereby achieving a very significant speedup. (After one large division the gcd problem is of normal size.) Heninger says in her blog that the bad keys occurred almost entirely in embedded applications, including "firewalls, routers, VPN devices, remote server administration devices, printers, projectors, and VOIP phones" from over 30 manufactures.

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Importance Of Network Security

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Maintenance Of Network Security

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