Firewall” refers to a method of separating the internal network and public access network, which is a kind of applied security technology based on modern communication network technology and information security technology, isolation technology. Increasingly used in the private network and public network interconnection environment, especially to access the Internet for the most.
A firewall is mainly the role of hardware and software in the internal and external network environment to produce a protective barrier, to prevent the computer from unsafe network factors to block. Only if the firewall agrees, the user can enter the computer, if not will be blocked from the outside, the firewall technology alarm function is very powerful, if the external user enters the computer, the firewall will quickly send out the corresponding alarm, and remind the user’s behaviour, and self-judgment to decide whether to allow external users to enter the internal, as long as the network environment of users, this firewall can be carried out. As long as the user is in the network environment, this firewall can carry out effective queries, and at the same time find the information towards the user to display, and then the user needs to be by their own needs to implement the corresponding settings of the firewall, the user is not allowed to block the behaviour. The firewall is also able to implement an effective view of the flow of information and data, and also be able to upload and download speed of data and information to master, to facilitate the use of the computer users have good control of the situation of judgement, the internal situation of the computer can also be viewed through this firewall, but also has the function of start-up and shutdown procedures, and the computer system has a logging function is also a firewall to the internal system of the computer in real-time. Firewall on the computer’s internal system real-time security situation and the daily traffic situation for the summary and organisation.
A firewall is an access control scale that is implemented when two networks are communicating, which maximises the ability to stop hackers in the network from accessing your network. It is a combination of components set up between different networks (such as a trusted corporate intranet and an untrusted public network) or network security domains. It is the only entrance and exit point of information between different networks or network security domains, which can control (allow, deny, monitor) the flow of information in and out of the network according to the security policy of the enterprise, and has strong anti-attack capability itself. It is an infrastructure for providing information security services and achieving network and information security. Logically, a firewall is a separator, a limiter, and an analyser that effectively monitors any activity between the intranet and the Internet to ensure the security of the internal network.
A firewall is a network security system used to monitor and control packets going in and out of a network to protect the network from unauthorized access and attacks. It is typically deployed at the edge of the network, between internal and external networks such as the Internet, to prevent malicious traffic, unauthorized access, and other security threats from entering the network. It includes stateful packet check filtering, static packet filtering, network address translation, application proxy filtering, intrusion prevention system filtering and anti-virus filtering.
From my reading I can understand that firewalls are used as a mechanism to separate parts of the network with different levels of security; thus, the purpose of a firewall is to determine an authorization policy that selects the traffic to be allowed based on a security policy expressed as a set of rules, commonly known as Access Control Lists (ACLs). These rules consist of a condition clause, which consists of a series of predicates on certain packet header fields, and an action clause, which is used to evaluate the action to be performed, in particular to allow or deny traffic.
When a new packet arrives at one of the firewall’s network interfaces, the value of the packet’s header is used to evaluate the predicates of the condition clause. If all predicates of a rule are true. If the packet matches only one rule, the action in its action clause is performed. Firewalls and security gateways are core elements of the network security infrastructure. As networks and services become more complex, managing access list rules becomes an error-prone task. Conflicts in policies can lead to security breaches and are often difficult to detect by visual or manual inspection alone.Firewall has developed a method to systematically classify the severity of rule conflicts and as a result proposes a solution to automatically resolve conflicts in firewalls.
Firewalls are capable of inspecting packets entering and leaving the network and deciding whether or not to allow those packets to pass based on preset security rules. Firewalls also enhance network security by blocking potentially malicious traffic and unauthorized access. Of course, firewalls have some limitations: (1) They cannot prevent insider threats, such as malicious internal users or infected internal systems. (2) Firewalls cannot solve all security problems; they are only a security component that needs to be used in conjunction with other security policies and technologies (e.g., intrusion detection systems, security event management systems, etc.).
Understand the firewall during the attack. It’s important for companies to install firewalls on their servers, networks, and websites, because if the firewall can’t filter all the packets that come through, it will drop the packets it can’t handle, rather than let them through. This approach protects the server from hackers, but if the firewall drops a large number of unpassable packets, it can create a self-inflicted denial of service attack. Therefore, it is critical that companies invest in firewalls with sufficient processing power to handle incoming network traffic. Firewalls can later run out of capacity, so companies must also reassess their incoming and growing network traffic to upgrade firewall capacity, write more filtering rules, and provide more firewall processing for each packet. The firewall must be able to filter traffic at line speed (the maximum speed of the line connected to the firewall)
Firewalls are a fundamental component of network security infrastructure, serving as a barrier between a trusted internal network and untrusted external networks, such as the internet. They monitor and control incoming and outgoing network traffic based on predetermined security rules or policies, thereby preventing unauthorized access, protecting against malicious attacks, and ensuring the confidentiality, integrity, and availability of network resources.
From reading the article, I concluded that a firewall is an access control scale implemented when two networks communicate, which can prevent hackers from accessing your network to the maximum extent possible. A combination of components that are set between different networks (or network security domains). It is the only entrance and exit of information between different networks or network security domains, and can control (allow, deny, monitor) the information flow in and out of the network according to the security policy of the enterprise, and has strong anti-attack capability. It is an infrastructure that provides information security services and realizes network and information security. Logically, a firewall is a separator, a limiter, and a analyzer that effectively monitors any activity between the Intranet and the Internet, ensuring the security of the internal network.
The firewall scans the network traffic flowing through it, filtering out attacks before they can be executed on the target computer. The firewall can also close ports that are not in use. It can also disable outgoing traffic on specific ports and block Trojan horses. Finally, it can block access from special sites, thus preventing all communication from unknown intruders.
Firewalls play a crucial role in network security by inspecting packets entering and leaving the network and making decisions based on preset security rules. They effectively block potentially malicious traffic and unauthorized access, thus enhancing overall network security. However, firewalls have their limitations, such as being unable to prevent insider threats or address all security issues alone. Therefore, they should be viewed as one component of a comprehensive security strategy, which also includes other technologies and policies like intrusion detection systems and security event management systems.
During an attack, it’s crucial to understand how firewalls operate. Companies must install firewalls on their servers, networks, and websites to filter incoming packets. If a firewall cannot handle all packets, it will discard those it cannot process, rather than allowing them to pass. This approach helps protect servers from hackers. However, if a firewall discards a significant number of packets, it can result in a self-inflicted denial of service attack. Therefore, investing in firewalls with sufficient processing power to handle incoming network traffic is essential. Companies must also continuously reassess their incoming and growing network traffic to upgrade firewall capacity, create additional filtering rules, and provide enhanced firewall processing for each packet. Ideally, the firewall should be capable of filtering traffic at line speed, ensuring maximum efficiency and protection.
Firewall is the core component of intrusion detection system. They create a divide between trusted and untrusted networks. When you add firewalls between networks, applications, and databases, they can also create multiple layers of security. Firewalls can’t stop all malicious activity, but they do play a role in a multi-layered defense system.
The firewall works with other servers configured to perform antivirus filtering. Traffic from the Internet usually reaches the firewall first. It will then be sent to the antivirus server. The anonymous behavior of traffic, such as viruses and worms, is analyzed. Then, depending on the Settings, it will go to the firewall and the target host, or directly to the target host.
Boyle and Panko Chapter 6 introduces the concept of firewalls and their crucial role in modern cybersecurity strategies. The chapter provides a comprehensive overview of firewalls, covering their definition, types, functionalities, and deployment considerations.
One notable aspect of the chapter is its emphasis on the importance of firewalls as a foundational security measure for protecting networks from unauthorized access and malicious activities. It highlights how firewalls serve as a barrier between internal networks and external threats, controlling the flow of traffic based on predetermined security rules.
Firewalls serve as a crucial barrier between a trusted internal network and untrusted external networks, such as the internet. One of the most impressive functions is packet filtering, where they examine data packets and decide whether to allow or block them based on a set of security rules. This capability helps prevent unauthorized access to or from private networks by monitoring and controlling incoming and outgoing network traffic. Firewalls can also perform stateful inspection, which tracks the state of active connections and ensures that only legitimate traffic is allowed. Additionally, they can implement network address translation (NAT), which hides internal IP addresses from external networks for added security. Overall, firewalls play a vital role in protecting networks from a variety of cyber threats and unauthorized access attempts.
I learned from this chapter that traffic overload can have serious consequences. When traffic spikes to the point where the firewall can’t handle it, the firewall will have to drop all incoming packets, which can pose a serious threat to network security. This ties in closely with what we discussed in the previous chapter and explains why DDoS attacks are so effective and why systems are prone to crashing under such attacks.
The book suggests addressing this challenge by purchasing a more powerful, higher-capacity firewall. However, given the constant growth in traffic, especially in the face of targeted attacks such as the Minecraft attack we learned about in class, attackers may utilize a large number of zombie computers to launch their attacks. Therefore, simply upgrading the specifications of a firewall is not enough to solve all the problems.
Additionally, it is equally critical to continually update and maintain the firewall. As new threats emerge, administrators must continually update filtering rules to ensure that the firewall is able to defend against the latest attack methods. A great firewall not only needs to be able to maintain efficient operation during traffic surges, but it also needs to have the ability to filter harmful packets and be able to operate at speeds close to the line’s maximum speed. In this way, the firewall can play an important role in securing the network.
In summary, traffic overload is an important issue in the field of network security. In order to meet this challenge, we need to constantly improve the performance and specifications of our firewalls, while keeping them continuously updated and maintained. Only in this way can we ensure that our networks remain stable and secure when faced with threats such as DDoS attacks.
After reading the article ,what I find interesting is how the firewall works.Firewalls are usually deployed at the edge of the network, for example between the internal network and the Internet.The firewall checks each incoming and outgoing packet and determines whether it is allowed to pass according to the configured security rules.Security rules can be based on factors such as source/destination IP address, port number, protocol type, and application type.
A firewall is a mechanism for checking every packet that passes through it. Firewalls have pass or deny mechanisms that determine whether packets should be allowed to pass to reach their destination. Firewalls can be divided into six types: stateful packet check filters, static packet filters, firewall filters, network address translation filters, application proxy filters, intrusion prevention system filters, and antivirus filters. Another important thing I learned from this article is firewall management. Although an organization can use a firewall to protect and detect network attacks, it is important to define firewall policies and control firewall security. When multiple security policies are implemented on the firewall, policy conflicts will not only affect the normal operation of the network, but also threaten network security. For different situations, the selection of firewall policies is very important. Policy conflicts between multiple domains occur from time to time, which seriously affects the execution efficiency of security policies
A firewall is a network security system that monitors and controls incoming and outgoing network traffic according to defined security rules. They act as a barrier between trusted internal networks and untrusted external networks such as the internet. Firewalls can be implemented in both hardware and software forms, and can be divided into different types based on their operational principles and deployment locations.
Firewall Types: This section describes different types of firewalls, including packet filtering firewalls, status detection firewalls, application layer gateways, and proxy servers. Packet filtering The firewall checks the headers of network packets and determines whether to allow or deny these packets according to predefined rules. The firewall tracks the state of the network connection and makes decisions based on the context of the connection. Application-level gateways and proxy servers provide more granular control by interacting directly with applications.
Firewall deployment: This chapter also describes different deployment scenarios for firewalls, including peripheral firewalls, masked subnets, and multi-homing firewalls. A perimeter firewall sits at the network boundary and protects internal resources from external threats. Filtering subnets introduces an additional layer of security by isolating the firewall from the internal network. Multi-host firewalls connect to multiple external networks for a more flexible and secure network topology.
Firewall Rules and Policies: This chapter emphasizes the importance of clearly defined and concise firewall rules and policies. It explains how to create effective rules that balance security and availability, and provides guidance on how to avoid common pitfalls, such as overly loose rules or complex rule sets that are difficult to manage.
Limitations of firewalls: Although firewalls are a key component of network security, they also have their limitations. This chapter discusses some of the challenges and limitations of firewalls, such as their inability to protect against insider threats, their reliance on accurate and up-to-date rule sets, and their potential to introduce performance bottlenecks.
A firewall is a network security device or software that monitors and controls network traffic to protect the network from unauthorized access, malicious attacks, and data breaches. It filters and blocks insecure or untrusted network traffic based on a set of rules and policies while allowing legitimate traffic to pass through.
The main functions of a firewall include:
1. **Packet Filtering**: The firewall examines network packets based on predefined rules and policies and decides whether to allow them through or block them. It can block traffic from untrusted sources, such as IP addresses in a blacklist or specific protocols.
2. **Access Control**: The firewall can restrict access to specific users, hosts, or networks. It can control who can access network resources based on user identity, IP address, time of day, and other conditions.
3. **Network Address Translation (NAT)**: The firewall can perform network address translation, converting internal private IP addresses to public IP addresses to hide the true topology of the internal network and enhance network security.
4. **Virtual Private Network (VPN) Support**: The firewall can provide VPN functionality, allowing remote users to securely access internal network resources through encrypted tunnels.
5. **Intrusion Detection and Prevention**: Some advanced firewalls have intrusion detection and prevention system (IDS/IPS) capabilities. They can detect and block malicious attacks such as port scanning, denial-of-service attacks, and malware.
6. **Logging and Reporting**: The firewall can log network traffic, events, and security incidents and generate logs and reports for security auditing and troubleshooting purposes.
Firewalls can be deployed at network boundaries, internal networks, and endpoint devices to provide layered protection. They are a critical component of network security, helping organizations defend against various network threats and ensuring the availability, integrity, and confidentiality of network resources.
What I gained from Chapter 6 Firewall reading is a better insight of the major function of a firewall, which to my understanding is basically a gatekeeper that monitors and prevents any attempts of unwelcome network traffic from coming through. A firewall filter is arranged with a set of rules that determines when to accept or deny entrance. If the packet appears to not be a preventable attack, then it is accepted in the network, otherwise it is denied or dropped. In the case there’s a traffic overload, all packets will be dropped for security purposes.
A firewall is a bottleneck in the security architecture of IT networks, used to restrict access from one network to another. All communication should be checked and restricted through the firewall, which is one of the strategies for implementing network security State packet check filters, network address translation filters, and application proxy filters, as well as other types of firewall, are crucial for providing different levels of security and protection.
Firewalls are network security systems that monitor and control incoming and outgoing network traffic based on defined security rules. They act as a barrier between trusted internal networks and untrusted external networks such as the Internet. Firewalls can be implemented in both hardware and software, and can be categorised into different types depending on how they work and where they are deployed.
1) packet filtering firewall, high-speed, application-independent, no state, only look at packet header port, address, service. First generation firewall
2) proxy firewall, trust and untrust communication between the bridge middleman, are relayed through the proxy. proxy first check the security of access requests, and then repackage forwarded to the destination host, the second generation of firewalls.
3) stateful firewall, check the status of each connection, third generation firewalls
4) dynamic packet firewall, support 1 high port, do not need to open all (punch holes). Fourth generation firewall
5) kernel proxy firewall, the kernel handles application layer information, the fifth generation firewall.
What I gained from Chapter 6 Firewall reading is a better insight of the major function of a firewall, which to my understanding is basically a gatekeeper that monitors and prevents any attempts of unwelcome network traffic from coming through. A firewall filter is arranged with a set of rules that determines when to accept or deny entrance. If the packet appears to not be a preventable attack, then it is accepted in the network, otherwise it is denied or dropped. In the case there’s a traffic overload, all packets will be dropped for security purposes.
The firewall is like its name, and he can check the packets entering and leaving the network and decide whether to allow them to pass according to the preset security rules. But it does not work for internal threats.
The key point I take away from this chapter is the SPI firewall, which stands for National Pocket Check.
SPI full state packet detection firewall refers to each connection including socket pair information: source address, destination address, source port and destination port; Protocol type, TCP connection status, and timeout period. Check whether packets are filtered on the firewall. In addition to completing the packet filtering work of a simple packet filtering firewall, it also maintains a table in its own memory that tracks the state of the connection, which has higher security than a simple packet filtering firewall.
The most advanced status Packet Detection (SPI) firewall provides the highest level of security. By default, it rejects all requests from external networks. It dynamically maintains all communications (connections) for internal network connections through firewalls. Only connections that respond to Intranet requests and match packets established in the status database can access the Intranet through the firewall. This scheme not only ensures the access of network users to Internet resources, but also prevents hackers from accessing internal network resources on the Internet.
The sixth chapter mainly discusses the concept, type, working principle of firewall and its role in network security. A firewall is a network security system used to monitor and control the flow of traffic to and from a network in order to protect the network from unauthorized access and other security threats.
A firewall is a network security device or software that restricts access to a network, thereby preventing unauthorized communications, malicious attacks, and data breaches. Different kinds of firewalls: packet filtering firewall, proxy server firewall, status monitoring firewall. Different types of firewalls have their own characteristics. The key to ensure network security is to choose the type of firewall that suits the needs of the organization and formulate reasonable firewall policies.
The main purpose of a firewall is to protect the network from unauthorized access and other security threats, thereby ensuring the security of the network and the integrity of the data. The importance of a firewall policy is that it defines a set of rules for what traffic should be allowed or denied. A reasonable firewall policy can ensure that only legitimate and secure traffic can enter the network, which greatly improves network security.
At first, I was initially confused when I read that a firewall self-destruct is considered fail-safe, but it does make sense. It is much better to exert too much force on the network and cause it to give up everything than to exert too much force and flood everything. Ideally, however, we want to avoid a situation where network usage is fail-safe in this regard. I would argue that this requires security engineers to purchase an adequate firewall to manage their traffic to avoid self-destruction.
One of the main points of this chapter is IPS and IDS. new filtering methods Intrusion Prevention Systems (IPS) are capable of detecting and stopping attacks that are more sophisticated than earlier forms of filtering including SPI. Only time will tell if IPS filtering can become the primary filtering method for border firewalls. Intrusion Prevention System filtering stems from an earlier technology-the Intrusion Detection System (IDS). the IDS has two serious limitations. These are specific controls. the IDS tends to generate too many false positives. in IDS parlance. The other problem is that the IDS approach is highly processing-intensive. This limits the amount of traffic an IDS can filter. Although Intrusion Prevention Systems (IPS) use IDS filtering methods, they actually stop certain types of attacks rather than just identifying them and generating alerts as IDS does.
Chun Liu says
Firewall” refers to a method of separating the internal network and public access network, which is a kind of applied security technology based on modern communication network technology and information security technology, isolation technology. Increasingly used in the private network and public network interconnection environment, especially to access the Internet for the most.
A firewall is mainly the role of hardware and software in the internal and external network environment to produce a protective barrier, to prevent the computer from unsafe network factors to block. Only if the firewall agrees, the user can enter the computer, if not will be blocked from the outside, the firewall technology alarm function is very powerful, if the external user enters the computer, the firewall will quickly send out the corresponding alarm, and remind the user’s behaviour, and self-judgment to decide whether to allow external users to enter the internal, as long as the network environment of users, this firewall can be carried out. As long as the user is in the network environment, this firewall can carry out effective queries, and at the same time find the information towards the user to display, and then the user needs to be by their own needs to implement the corresponding settings of the firewall, the user is not allowed to block the behaviour. The firewall is also able to implement an effective view of the flow of information and data, and also be able to upload and download speed of data and information to master, to facilitate the use of the computer users have good control of the situation of judgement, the internal situation of the computer can also be viewed through this firewall, but also has the function of start-up and shutdown procedures, and the computer system has a logging function is also a firewall to the internal system of the computer in real-time. Firewall on the computer’s internal system real-time security situation and the daily traffic situation for the summary and organisation.
A firewall is an access control scale that is implemented when two networks are communicating, which maximises the ability to stop hackers in the network from accessing your network. It is a combination of components set up between different networks (such as a trusted corporate intranet and an untrusted public network) or network security domains. It is the only entrance and exit point of information between different networks or network security domains, which can control (allow, deny, monitor) the flow of information in and out of the network according to the security policy of the enterprise, and has strong anti-attack capability itself. It is an infrastructure for providing information security services and achieving network and information security. Logically, a firewall is a separator, a limiter, and an analyser that effectively monitors any activity between the intranet and the Internet to ensure the security of the internal network.
Guanhua Xiao says
A firewall is a network security system used to monitor and control packets going in and out of a network to protect the network from unauthorized access and attacks. It is typically deployed at the edge of the network, between internal and external networks such as the Internet, to prevent malicious traffic, unauthorized access, and other security threats from entering the network. It includes stateful packet check filtering, static packet filtering, network address translation, application proxy filtering, intrusion prevention system filtering and anti-virus filtering.
Xiaozhi Shi says
From my reading I can understand that firewalls are used as a mechanism to separate parts of the network with different levels of security; thus, the purpose of a firewall is to determine an authorization policy that selects the traffic to be allowed based on a security policy expressed as a set of rules, commonly known as Access Control Lists (ACLs). These rules consist of a condition clause, which consists of a series of predicates on certain packet header fields, and an action clause, which is used to evaluate the action to be performed, in particular to allow or deny traffic.
When a new packet arrives at one of the firewall’s network interfaces, the value of the packet’s header is used to evaluate the predicates of the condition clause. If all predicates of a rule are true. If the packet matches only one rule, the action in its action clause is performed. Firewalls and security gateways are core elements of the network security infrastructure. As networks and services become more complex, managing access list rules becomes an error-prone task. Conflicts in policies can lead to security breaches and are often difficult to detect by visual or manual inspection alone.Firewall has developed a method to systematically classify the severity of rule conflicts and as a result proposes a solution to automatically resolve conflicts in firewalls.
Yawen Du says
Firewalls are capable of inspecting packets entering and leaving the network and deciding whether or not to allow those packets to pass based on preset security rules. Firewalls also enhance network security by blocking potentially malicious traffic and unauthorized access. Of course, firewalls have some limitations: (1) They cannot prevent insider threats, such as malicious internal users or infected internal systems. (2) Firewalls cannot solve all security problems; they are only a security component that needs to be used in conjunction with other security policies and technologies (e.g., intrusion detection systems, security event management systems, etc.).
Shijie Yang says
Understand the firewall during the attack. It’s important for companies to install firewalls on their servers, networks, and websites, because if the firewall can’t filter all the packets that come through, it will drop the packets it can’t handle, rather than let them through. This approach protects the server from hackers, but if the firewall drops a large number of unpassable packets, it can create a self-inflicted denial of service attack. Therefore, it is critical that companies invest in firewalls with sufficient processing power to handle incoming network traffic. Firewalls can later run out of capacity, so companies must also reassess their incoming and growing network traffic to upgrade firewall capacity, write more filtering rules, and provide more firewall processing for each packet. The firewall must be able to filter traffic at line speed (the maximum speed of the line connected to the firewall)
Xinyi Peng says
Firewalls are a fundamental component of network security infrastructure, serving as a barrier between a trusted internal network and untrusted external networks, such as the internet. They monitor and control incoming and outgoing network traffic based on predetermined security rules or policies, thereby preventing unauthorized access, protecting against malicious attacks, and ensuring the confidentiality, integrity, and availability of network resources.
Yuanjun Xie says
From reading the article, I concluded that a firewall is an access control scale implemented when two networks communicate, which can prevent hackers from accessing your network to the maximum extent possible. A combination of components that are set between different networks (or network security domains). It is the only entrance and exit of information between different networks or network security domains, and can control (allow, deny, monitor) the information flow in and out of the network according to the security policy of the enterprise, and has strong anti-attack capability. It is an infrastructure that provides information security services and realizes network and information security. Logically, a firewall is a separator, a limiter, and a analyzer that effectively monitors any activity between the Intranet and the Internet, ensuring the security of the internal network.
The firewall scans the network traffic flowing through it, filtering out attacks before they can be executed on the target computer. The firewall can also close ports that are not in use. It can also disable outgoing traffic on specific ports and block Trojan horses. Finally, it can block access from special sites, thus preventing all communication from unknown intruders.
Zhang Yunpeng says
Firewalls play a crucial role in network security by inspecting packets entering and leaving the network and making decisions based on preset security rules. They effectively block potentially malicious traffic and unauthorized access, thus enhancing overall network security. However, firewalls have their limitations, such as being unable to prevent insider threats or address all security issues alone. Therefore, they should be viewed as one component of a comprehensive security strategy, which also includes other technologies and policies like intrusion detection systems and security event management systems.
During an attack, it’s crucial to understand how firewalls operate. Companies must install firewalls on their servers, networks, and websites to filter incoming packets. If a firewall cannot handle all packets, it will discard those it cannot process, rather than allowing them to pass. This approach helps protect servers from hackers. However, if a firewall discards a significant number of packets, it can result in a self-inflicted denial of service attack. Therefore, investing in firewalls with sufficient processing power to handle incoming network traffic is essential. Companies must also continuously reassess their incoming and growing network traffic to upgrade firewall capacity, create additional filtering rules, and provide enhanced firewall processing for each packet. Ideally, the firewall should be capable of filtering traffic at line speed, ensuring maximum efficiency and protection.
Yujie Cao says
Firewall is the core component of intrusion detection system. They create a divide between trusted and untrusted networks. When you add firewalls between networks, applications, and databases, they can also create multiple layers of security. Firewalls can’t stop all malicious activity, but they do play a role in a multi-layered defense system.
The firewall works with other servers configured to perform antivirus filtering. Traffic from the Internet usually reaches the firewall first. It will then be sent to the antivirus server. The anonymous behavior of traffic, such as viruses and worms, is analyzed. Then, depending on the Settings, it will go to the firewall and the target host, or directly to the target host.
Shuting Zhang says
Boyle and Panko Chapter 6 introduces the concept of firewalls and their crucial role in modern cybersecurity strategies. The chapter provides a comprehensive overview of firewalls, covering their definition, types, functionalities, and deployment considerations.
One notable aspect of the chapter is its emphasis on the importance of firewalls as a foundational security measure for protecting networks from unauthorized access and malicious activities. It highlights how firewalls serve as a barrier between internal networks and external threats, controlling the flow of traffic based on predetermined security rules.
Hongli Ma says
Firewalls serve as a crucial barrier between a trusted internal network and untrusted external networks, such as the internet. One of the most impressive functions is packet filtering, where they examine data packets and decide whether to allow or block them based on a set of security rules. This capability helps prevent unauthorized access to or from private networks by monitoring and controlling incoming and outgoing network traffic. Firewalls can also perform stateful inspection, which tracks the state of active connections and ensures that only legitimate traffic is allowed. Additionally, they can implement network address translation (NAT), which hides internal IP addresses from external networks for added security. Overall, firewalls play a vital role in protecting networks from a variety of cyber threats and unauthorized access attempts.
Shuyi Dong says
I learned from this chapter that traffic overload can have serious consequences. When traffic spikes to the point where the firewall can’t handle it, the firewall will have to drop all incoming packets, which can pose a serious threat to network security. This ties in closely with what we discussed in the previous chapter and explains why DDoS attacks are so effective and why systems are prone to crashing under such attacks.
The book suggests addressing this challenge by purchasing a more powerful, higher-capacity firewall. However, given the constant growth in traffic, especially in the face of targeted attacks such as the Minecraft attack we learned about in class, attackers may utilize a large number of zombie computers to launch their attacks. Therefore, simply upgrading the specifications of a firewall is not enough to solve all the problems.
Additionally, it is equally critical to continually update and maintain the firewall. As new threats emerge, administrators must continually update filtering rules to ensure that the firewall is able to defend against the latest attack methods. A great firewall not only needs to be able to maintain efficient operation during traffic surges, but it also needs to have the ability to filter harmful packets and be able to operate at speeds close to the line’s maximum speed. In this way, the firewall can play an important role in securing the network.
In summary, traffic overload is an important issue in the field of network security. In order to meet this challenge, we need to constantly improve the performance and specifications of our firewalls, while keeping them continuously updated and maintained. Only in this way can we ensure that our networks remain stable and secure when faced with threats such as DDoS attacks.
Haoran Wang says
After reading the article ,what I find interesting is how the firewall works.Firewalls are usually deployed at the edge of the network, for example between the internal network and the Internet.The firewall checks each incoming and outgoing packet and determines whether it is allowed to pass according to the configured security rules.Security rules can be based on factors such as source/destination IP address, port number, protocol type, and application type.
Yiwei Hu says
A firewall is a mechanism for checking every packet that passes through it. Firewalls have pass or deny mechanisms that determine whether packets should be allowed to pass to reach their destination. Firewalls can be divided into six types: stateful packet check filters, static packet filters, firewall filters, network address translation filters, application proxy filters, intrusion prevention system filters, and antivirus filters. Another important thing I learned from this article is firewall management. Although an organization can use a firewall to protect and detect network attacks, it is important to define firewall policies and control firewall security. When multiple security policies are implemented on the firewall, policy conflicts will not only affect the normal operation of the network, but also threaten network security. For different situations, the selection of firewall policies is very important. Policy conflicts between multiple domains occur from time to time, which seriously affects the execution efficiency of security policies
Chenhao Zhang says
A firewall is a network security system that monitors and controls incoming and outgoing network traffic according to defined security rules. They act as a barrier between trusted internal networks and untrusted external networks such as the internet. Firewalls can be implemented in both hardware and software forms, and can be divided into different types based on their operational principles and deployment locations.
Firewall Types: This section describes different types of firewalls, including packet filtering firewalls, status detection firewalls, application layer gateways, and proxy servers. Packet filtering The firewall checks the headers of network packets and determines whether to allow or deny these packets according to predefined rules. The firewall tracks the state of the network connection and makes decisions based on the context of the connection. Application-level gateways and proxy servers provide more granular control by interacting directly with applications.
Firewall deployment: This chapter also describes different deployment scenarios for firewalls, including peripheral firewalls, masked subnets, and multi-homing firewalls. A perimeter firewall sits at the network boundary and protects internal resources from external threats. Filtering subnets introduces an additional layer of security by isolating the firewall from the internal network. Multi-host firewalls connect to multiple external networks for a more flexible and secure network topology.
Firewall Rules and Policies: This chapter emphasizes the importance of clearly defined and concise firewall rules and policies. It explains how to create effective rules that balance security and availability, and provides guidance on how to avoid common pitfalls, such as overly loose rules or complex rule sets that are difficult to manage.
Limitations of firewalls: Although firewalls are a key component of network security, they also have their limitations. This chapter discusses some of the challenges and limitations of firewalls, such as their inability to protect against insider threats, their reliance on accurate and up-to-date rule sets, and their potential to introduce performance bottlenecks.
Zhaomeng Wang says
A firewall is a network security device or software that monitors and controls network traffic to protect the network from unauthorized access, malicious attacks, and data breaches. It filters and blocks insecure or untrusted network traffic based on a set of rules and policies while allowing legitimate traffic to pass through.
The main functions of a firewall include:
1. **Packet Filtering**: The firewall examines network packets based on predefined rules and policies and decides whether to allow them through or block them. It can block traffic from untrusted sources, such as IP addresses in a blacklist or specific protocols.
2. **Access Control**: The firewall can restrict access to specific users, hosts, or networks. It can control who can access network resources based on user identity, IP address, time of day, and other conditions.
3. **Network Address Translation (NAT)**: The firewall can perform network address translation, converting internal private IP addresses to public IP addresses to hide the true topology of the internal network and enhance network security.
4. **Virtual Private Network (VPN) Support**: The firewall can provide VPN functionality, allowing remote users to securely access internal network resources through encrypted tunnels.
5. **Intrusion Detection and Prevention**: Some advanced firewalls have intrusion detection and prevention system (IDS/IPS) capabilities. They can detect and block malicious attacks such as port scanning, denial-of-service attacks, and malware.
6. **Logging and Reporting**: The firewall can log network traffic, events, and security incidents and generate logs and reports for security auditing and troubleshooting purposes.
Firewalls can be deployed at network boundaries, internal networks, and endpoint devices to provide layered protection. They are a critical component of network security, helping organizations defend against various network threats and ensuring the availability, integrity, and confidentiality of network resources.
Hao Zhang says
What I gained from Chapter 6 Firewall reading is a better insight of the major function of a firewall, which to my understanding is basically a gatekeeper that monitors and prevents any attempts of unwelcome network traffic from coming through. A firewall filter is arranged with a set of rules that determines when to accept or deny entrance. If the packet appears to not be a preventable attack, then it is accepted in the network, otherwise it is denied or dropped. In the case there’s a traffic overload, all packets will be dropped for security purposes.
Yuming He says
A firewall is a bottleneck in the security architecture of IT networks, used to restrict access from one network to another. All communication should be checked and restricted through the firewall, which is one of the strategies for implementing network security State packet check filters, network address translation filters, and application proxy filters, as well as other types of firewall, are crucial for providing different levels of security and protection.
Yue Wang says
Firewalls are network security systems that monitor and control incoming and outgoing network traffic based on defined security rules. They act as a barrier between trusted internal networks and untrusted external networks such as the Internet. Firewalls can be implemented in both hardware and software, and can be categorised into different types depending on how they work and where they are deployed.
1) packet filtering firewall, high-speed, application-independent, no state, only look at packet header port, address, service. First generation firewall
2) proxy firewall, trust and untrust communication between the bridge middleman, are relayed through the proxy. proxy first check the security of access requests, and then repackage forwarded to the destination host, the second generation of firewalls.
3) stateful firewall, check the status of each connection, third generation firewalls
4) dynamic packet firewall, support 1 high port, do not need to open all (punch holes). Fourth generation firewall
5) kernel proxy firewall, the kernel handles application layer information, the fifth generation firewall.
Chunqi Liu says
What I gained from Chapter 6 Firewall reading is a better insight of the major function of a firewall, which to my understanding is basically a gatekeeper that monitors and prevents any attempts of unwelcome network traffic from coming through. A firewall filter is arranged with a set of rules that determines when to accept or deny entrance. If the packet appears to not be a preventable attack, then it is accepted in the network, otherwise it is denied or dropped. In the case there’s a traffic overload, all packets will be dropped for security purposes.
Xuanwen Zheng says
The firewall is like its name, and he can check the packets entering and leaving the network and decide whether to allow them to pass according to the preset security rules. But it does not work for internal threats.
Nana Li says
The key point I take away from this chapter is the SPI firewall, which stands for National Pocket Check.
SPI full state packet detection firewall refers to each connection including socket pair information: source address, destination address, source port and destination port; Protocol type, TCP connection status, and timeout period. Check whether packets are filtered on the firewall. In addition to completing the packet filtering work of a simple packet filtering firewall, it also maintains a table in its own memory that tracks the state of the connection, which has higher security than a simple packet filtering firewall.
The most advanced status Packet Detection (SPI) firewall provides the highest level of security. By default, it rejects all requests from external networks. It dynamically maintains all communications (connections) for internal network connections through firewalls. Only connections that respond to Intranet requests and match packets established in the status database can access the Intranet through the firewall. This scheme not only ensures the access of network users to Internet resources, but also prevents hackers from accessing internal network resources on the Internet.
Haixu Yao says
The sixth chapter mainly discusses the concept, type, working principle of firewall and its role in network security. A firewall is a network security system used to monitor and control the flow of traffic to and from a network in order to protect the network from unauthorized access and other security threats.
A firewall is a network security device or software that restricts access to a network, thereby preventing unauthorized communications, malicious attacks, and data breaches. Different kinds of firewalls: packet filtering firewall, proxy server firewall, status monitoring firewall. Different types of firewalls have their own characteristics. The key to ensure network security is to choose the type of firewall that suits the needs of the organization and formulate reasonable firewall policies.
The main purpose of a firewall is to protect the network from unauthorized access and other security threats, thereby ensuring the security of the network and the integrity of the data. The importance of a firewall policy is that it defines a set of rules for what traffic should be allowed or denied. A reasonable firewall policy can ensure that only legitimate and secure traffic can enter the network, which greatly improves network security.
Yue Ma says
At first, I was initially confused when I read that a firewall self-destruct is considered fail-safe, but it does make sense. It is much better to exert too much force on the network and cause it to give up everything than to exert too much force and flood everything. Ideally, however, we want to avoid a situation where network usage is fail-safe in this regard. I would argue that this requires security engineers to purchase an adequate firewall to manage their traffic to avoid self-destruction.
Hao Li says
One of the main points of this chapter is IPS and IDS. new filtering methods Intrusion Prevention Systems (IPS) are capable of detecting and stopping attacks that are more sophisticated than earlier forms of filtering including SPI. Only time will tell if IPS filtering can become the primary filtering method for border firewalls. Intrusion Prevention System filtering stems from an earlier technology-the Intrusion Detection System (IDS). the IDS has two serious limitations. These are specific controls. the IDS tends to generate too many false positives. in IDS parlance. The other problem is that the IDS approach is highly processing-intensive. This limits the amount of traffic an IDS can filter. Although Intrusion Prevention Systems (IPS) use IDS filtering methods, they actually stop certain types of attacks rather than just identifying them and generating alerts as IDS does.