Network Security

Securing Client/Server Transactions The three basic ways that security is implemented in the area of client/server transaction. The first area is firewalls. The basic idea of a firewall to monitor traffic from a trusted network ( a company’s internal network) to an untrusted network (such as the Internet). Firewalls fall into two categories, “proxies” and “packet-filtering” firewalls. Packet-filtering determines whether a packet is allowed or disallowed depending on the source of the packet and the contents of it.

Security policies are a series of rules that define what traffic is permissible and what traffic is to be blocked or denied. These are not universal rules, and there are many different sets of rules for a single company with multiple connections. A web server connected to the Internet may be configured only to allow traffic on port 80 for HTTP, and have all other ports blocked. An e-mail server may have only necessary ports for e-mail open, with others blocked. A key to security policies for firewalls is the same as has been seen for other security policies, the principle of least access.

Circuit-layer firewalls can block packets based on the host name and other IP session information such as flags and sequencing numbers” (Grimes, 2003). Some recent firewalls even include autoban features that help monitor network activity and autoban a point of entry (often IP address or port) that alleviates known attacks or patterns of attacks such as DDOS. Many firewalls now include monitoring and reporting activities to alert Information technology staff that an issue is or has occurred and what steps were taken automatically by the firewall to prevent the issue. ... ... middle of paper ... ...h as viruses or tracking mechanisms, and more. Newer software based firewalls have built in technology that helps in this type of filtering upon initial implementation.

A firewall is a set of related programs, located at a network gateway server, that protects the resources of a private network from users from other networks. (The term also implies the security policy that is used with the programs.) An enterprise with an intranet that allows its workers access to the wider Internet installs a firewall to prevent outsiders from accessing its own private data resources and for controlling what outside resources its own users have access to. Basically, a firewall, working closely with a router program, examines each network packet to determine whether to forward it toward its destination. A firewall also includes or works with a proxy server that makes network requests on behalf of workstation users.

SSH is vulnerable to the man in the middle attack by unauthenticated users. SSL stands for Secure Sockets Layer. This protocol provides a secure channel between two machines located at different locations. It is used for the protection of transit data and also recognising the communication machine. Basically SSL provides security for web based applications like internet banking.

Encryption and password security is normally the best way to keep your data in the correct hands. Another way is install a firewall. A firewall is a system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both and are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet. There are several types of firewall techniques: • Packet Filter: Packet filtering looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules.

The use of electronic locks would control and log all access to the room containing the hardware. The electronic locks could be a PIN and password or fingerprint scanner (biometrics). The use of video and audio surveillance would provide physical proof of unauthorized access that could compromise the hardware. Data Link Layer The second layer of the OSI model is the data link layer. This is the layer that transports the data between network nodes in a wide area network (WAN) or on the same local area network (LAN) between nodes.

VoIP. Retrieved June 11, 2005, from the World Wide Web: http://www.wikipedia.org

The other method of securing files is by encrypting the information in the files using an Encrypting File System (EFS), which employs public key encryption privileges (Strengthen Your Users' File Security, 2003). A firewall prevents access to an internal system from the outside the company via the internet on any open ports. A firewall will also prevent internal network users from accessing certain internet sites which could be dangerous or offensive (Shay, 2004). The firewall acts at the OSI model's layers three and four by searching packets for certain types of headers (Shay, 2004). So, firewalls differ from file security because anyone inside the company can theoretically access files behind the firewall, while file security provides internal security against a company's own workers.

I read papers and had a solid understanding of OVERVIEW OF FIREWALLS A Firewall is basically a security function which prevents our systems from attacks. That is it acts as wall between our system and remote attackers and makes it difficult for attackers to attack. It is set of related programs which is located at network gateway server which protects private networks from any other network users. . It is set of rules that determine whether packets are safe or not.