20-09-2012, 10:40 AM
Network Security
NETWORK SECURITY (1).doc (Size: 234.5 KB / Downloads: 28)
INTRODUCTION
Although the history of the Internet is relatively short, its growth has been dynamically explosive. The number of Internet users worldwide has grown from 95 million to 130 million in 1998, and it is projected that there will be 350 million users in the year 2003 (eMarketer, 1998). The Internet is a worldwide collection of networks that links together millions of computers by various means, such as modems, fiber optic lines, routers, and servers. It provides connections to businesses, the government, industries, educational institutions, and individuals.
Each of these organizations has become increasingly dependent on networks and distributed computing and processing systems. Furthermore, because they possess a critical and integral asset of information, internetworking security and what measures to protect this information has become a major area of concern. In this report we will address the key concepts of network security, common network vulnerabilities, network security threats and attacks, security measures and tools, and the development of a network security policy and proper violation response plan.
A breach in network security could cost your company a great deal in lost productivity, lost data, repair work, and loss of confidence among customers, partners, and employees. But these damages are preventable. You just need a solid security strategy and a well-planned implementation. With the explosion of the public Internet and e-commerce, private computers and computer networks are increasingly vulnerable to damaging attacks. Hackers, viruses, vindictive employees, and even human error all represent clear and present dangers to networks. And all computer users, from
The most casual Internet surfers to large enterprises could be affected by network security breaches.
The needs for security
1. Keep outsiders from entering the organization and gaining access to sensitive or private information. Access can be gained physically or virtually.
2. Prevent unauthorized information from leaving the premises.
3. Monitor and control internal employees’ access to information and systems.
Basic approach
The first step in developing a security policy is recognizing the need for one. To begin designing the policy, it is important to first determine what the policy should cover. Additionally, the policy should be integrated and cohesive with existing organizational policies within the company.
In general, by asking yourself the following questions, you should be able to deter-mine how robust your security system needs to be, as well as ensure that the security yields cost benefits.
1. What am I trying to protect?
2. From what and whom do I need to protect it?
3. How likely are the threats and whatare the consequences if they happen?
4. Can the assets be covered in a cost-effective security manner?
5. And finally, have I reviewed the process and improved any weaknesses?
Once you have the answers to these questions, you can begin designing an information security process. The process should take into consideration that information is valuable to your company and that you have exclusive right to the information. The information and systems must be protected from fraud, disclosure, and intentional misuses. Additionally, the data and software must be securely stored and guarded. The policy should define ac-accountability for information at each employee level.
The security policy developed must con-form to existing policies, rules, regulations and laws to which the organization is subject. Another important element that of-ten is overlooked is the value of collaboration when designing policies. A security policy should be a joint effort by technical Personnel who understand the full ramifications of the proposed policy and the implementation of the policy, and by the decision makers who have the power and responsibility for enforcing the policy.
Without the joint development process, the organization risks implementation of a process that is neither enforceable nor useable.
Identifying the threats
When examining the possible threats, a business should consider both internal and external sources. The threats should be examined with the perspective of what the potential loss might be according to the protected assets.
A common threat is disclosing information. It is necessary to determine how valuable and sensitive the information stored on the computer systems is. This could be a pricing proposal, a technical paper or perhaps guides to future product development market initiatives. Consider placing passwords and encrypting potentially valuable information. How many computers in businesses today, using only a basic password, contain access to this sort of valuable data? Unfortunately too many businesses ignore this easy-to-implement practice.
One of the most common threats is unauthorized access to computing facilities. Unauthorized access is the use of any computer resource or facility without prior permission to use those resources that can take place in a variety of ways. One way is by the use of another person’s account to gain access to a system, facility or application.
NETWORK SECURITY THREATS AND ATTACKS
When a network is connected to the Internet to increase information sharing, communications, or productivity, the network is vulnerable to potential intrusions and attacks. Areas where potential intruders can enter may be dial-up access points, network connections, or misconfigured hosts.
Misconfigured hosts, frequently overlooked as points of network entry can be network systems that (1) use unprotected login accounts (such as guest accounts), (2) employ extensive trust in remote commands, (3) have illegal modems attached to them, or (4) use easy-to-break passwords (Cisco Systems, 1997). Security threats are classified as passive or active (Stallings & Van Slyke, 1998). Passive attacks involve eavesdropping on, or monitoring, transmissions without actually disturbing the network. The main concern of the point of vulnerability in the net-work is eavesdropping by another employee or unauthorized user. Data is transmitted in the form of frames or packets containing the source and destination address, and other related information. An eavesdropper can monitor the traffic of this information on the network. Individuals who attempt to read privileged data, perform unauthorized modification to data, or disrupt the system, on the other hand, carry out active attacks. There are many ways in which to attack the network security.
Management of system passwords
Going back a few years, employees used secret handshakes and code words to identify their right to use facilities or enter a building. Alpha bravo five, left shake right shake four finger dribble provided access to ever trade secret in the organization. This age-old tradition actually is still in place today, just in a different format. Now, systems and applications can assign, log and track an employee’s access to the network or facility by use of passwords and system identification numbers.
Each employee, contractor, or vendor accessing an organizations system should have a unique user ID and a private password. In addition, personnel needing access to systems, building infrastructure, networks and applications that access data in the organization should have prior written approval from an appropriate manager or supervisor. Requests for changes to account access also should follow established written procedures.
NETWORK SECURITY (1).doc (Size: 234.5 KB / Downloads: 28)
INTRODUCTION
Although the history of the Internet is relatively short, its growth has been dynamically explosive. The number of Internet users worldwide has grown from 95 million to 130 million in 1998, and it is projected that there will be 350 million users in the year 2003 (eMarketer, 1998). The Internet is a worldwide collection of networks that links together millions of computers by various means, such as modems, fiber optic lines, routers, and servers. It provides connections to businesses, the government, industries, educational institutions, and individuals.
Each of these organizations has become increasingly dependent on networks and distributed computing and processing systems. Furthermore, because they possess a critical and integral asset of information, internetworking security and what measures to protect this information has become a major area of concern. In this report we will address the key concepts of network security, common network vulnerabilities, network security threats and attacks, security measures and tools, and the development of a network security policy and proper violation response plan.
A breach in network security could cost your company a great deal in lost productivity, lost data, repair work, and loss of confidence among customers, partners, and employees. But these damages are preventable. You just need a solid security strategy and a well-planned implementation. With the explosion of the public Internet and e-commerce, private computers and computer networks are increasingly vulnerable to damaging attacks. Hackers, viruses, vindictive employees, and even human error all represent clear and present dangers to networks. And all computer users, from
The most casual Internet surfers to large enterprises could be affected by network security breaches.
The needs for security
1. Keep outsiders from entering the organization and gaining access to sensitive or private information. Access can be gained physically or virtually.
2. Prevent unauthorized information from leaving the premises.
3. Monitor and control internal employees’ access to information and systems.
Basic approach
The first step in developing a security policy is recognizing the need for one. To begin designing the policy, it is important to first determine what the policy should cover. Additionally, the policy should be integrated and cohesive with existing organizational policies within the company.
In general, by asking yourself the following questions, you should be able to deter-mine how robust your security system needs to be, as well as ensure that the security yields cost benefits.
1. What am I trying to protect?
2. From what and whom do I need to protect it?
3. How likely are the threats and whatare the consequences if they happen?
4. Can the assets be covered in a cost-effective security manner?
5. And finally, have I reviewed the process and improved any weaknesses?
Once you have the answers to these questions, you can begin designing an information security process. The process should take into consideration that information is valuable to your company and that you have exclusive right to the information. The information and systems must be protected from fraud, disclosure, and intentional misuses. Additionally, the data and software must be securely stored and guarded. The policy should define ac-accountability for information at each employee level.
The security policy developed must con-form to existing policies, rules, regulations and laws to which the organization is subject. Another important element that of-ten is overlooked is the value of collaboration when designing policies. A security policy should be a joint effort by technical Personnel who understand the full ramifications of the proposed policy and the implementation of the policy, and by the decision makers who have the power and responsibility for enforcing the policy.
Without the joint development process, the organization risks implementation of a process that is neither enforceable nor useable.
Identifying the threats
When examining the possible threats, a business should consider both internal and external sources. The threats should be examined with the perspective of what the potential loss might be according to the protected assets.
A common threat is disclosing information. It is necessary to determine how valuable and sensitive the information stored on the computer systems is. This could be a pricing proposal, a technical paper or perhaps guides to future product development market initiatives. Consider placing passwords and encrypting potentially valuable information. How many computers in businesses today, using only a basic password, contain access to this sort of valuable data? Unfortunately too many businesses ignore this easy-to-implement practice.
One of the most common threats is unauthorized access to computing facilities. Unauthorized access is the use of any computer resource or facility without prior permission to use those resources that can take place in a variety of ways. One way is by the use of another person’s account to gain access to a system, facility or application.
NETWORK SECURITY THREATS AND ATTACKS
When a network is connected to the Internet to increase information sharing, communications, or productivity, the network is vulnerable to potential intrusions and attacks. Areas where potential intruders can enter may be dial-up access points, network connections, or misconfigured hosts.
Misconfigured hosts, frequently overlooked as points of network entry can be network systems that (1) use unprotected login accounts (such as guest accounts), (2) employ extensive trust in remote commands, (3) have illegal modems attached to them, or (4) use easy-to-break passwords (Cisco Systems, 1997). Security threats are classified as passive or active (Stallings & Van Slyke, 1998). Passive attacks involve eavesdropping on, or monitoring, transmissions without actually disturbing the network. The main concern of the point of vulnerability in the net-work is eavesdropping by another employee or unauthorized user. Data is transmitted in the form of frames or packets containing the source and destination address, and other related information. An eavesdropper can monitor the traffic of this information on the network. Individuals who attempt to read privileged data, perform unauthorized modification to data, or disrupt the system, on the other hand, carry out active attacks. There are many ways in which to attack the network security.
Management of system passwords
Going back a few years, employees used secret handshakes and code words to identify their right to use facilities or enter a building. Alpha bravo five, left shake right shake four finger dribble provided access to ever trade secret in the organization. This age-old tradition actually is still in place today, just in a different format. Now, systems and applications can assign, log and track an employee’s access to the network or facility by use of passwords and system identification numbers.
Each employee, contractor, or vendor accessing an organizations system should have a unique user ID and a private password. In addition, personnel needing access to systems, building infrastructure, networks and applications that access data in the organization should have prior written approval from an appropriate manager or supervisor. Requests for changes to account access also should follow established written procedures.