Biblio

"Security first" is the most concerned issue of Linux administrators. Security refers to the integrity of data. The authentication security and integrity of data are higher than the privacy security of data. Firewall is used to realize the function of access control under Linux. It is divided into hardware or software firewall. No matter in which network, the firewall must work at the edge of the network. Our task is to define how the firewall works. This is the firewall's policies and rules, so that it can detect the IP and data in and out of the network. At present, there are three or four layers of firewalls on the market, which are called network layer firewalls, and seven layers of firewalls, which are actually the gateway of the agent layer. But for the seven layer firewall, no matter what your source port or target port, source address or target address is, it will check all your things. Therefore, the seven layer firewall is more secure, but it brings lower efficiency. Therefore, the usual firewall schemes on the market are a combination of the two. And because we all need to access from the port controlled by the firewall, the work efficiency of the firewall has become the most important control of how much data users can access. This paper introduces two types of firewalls iptables and TCP\_Wrappers. What are the differences between the use policies, rules and structures of the two firewalls? This is the problem to be discussed in this paper.

Smart Security Solutions are in high demand with the ever-increasing vulnerabilities within the IT domain. Adjusting to a Work-From-Home (WFH) culture has become mandatory by maintaining required core security principles. Therefore, implementing and maintaining a secure Smart Home System has become even more challenging. ARGUS provides an overall network security coverage for both incoming and outgoing traffic, a firewall and an adaptive bandwidth management system and a sophisticated CCTV surveillance capability. ARGUS is such a system that is implemented into an existing router incorporating cloud and Machine Learning (ML) technology to ensure seamless connectivity across multiple devices, including IoT devices at a low migration cost for the customer. The aggregation of the above features makes ARGUS an ideal solution for existing Smart Home System service providers and users where hardware and infrastructure is also allocated. ARGUS was tested on a small-scale smart home environment with a Raspberry Pi 4 Model B controller. Its intrusion detection system identified an intrusion with 96% accuracy while the physical surveillance system predicts the user with 81% accuracy.

Firewalls are security devices that perform network traffic filtering. They are ubiquitous in the industry and are a common method used to enforce organizational security policy. Security policy is specified on a high level of abstraction, with statements such as "web browsing is allowed only on workstations inside the office network", and needs to be translated into low-level firewall rules to be enforceable. There has been a lot of work regarding optimization, analysis and platform independence of firewall rules, but an area that has seen much less success is automatic translation of high-level security policies into firewall rules. In addition to improving rules’ readability, such translation would make it easier to detect errors.This paper surveys of over twenty papers that aim to generate firewall rules according to a security policy specified on a higher level of abstraction. It also presents an overview of similar features in modern firewall systems. Most approaches define specialized domain languages that get compiled into firewall rule sets, with some of them relying on formal specification, ontology, or graphical models. The approaches’ have improved over time, but there are still many drawbacks that need to be solved before wider application.

The number of Mobile device users in the word has evolved rapidly. Many internet users currently want to connect the internet for all utilities automatically. One of the technologies in the IPv6 network, which supports data access from moving users, is IPv6 Mobile protocol. In its mobility, the users on a range of networks can move the range to another network. High demand for this technology will interest to a hacker or a cracker to carry out an attack. One of them is a DoS attack that compromises a target to denial its services. A firewall is usually used to protect networks from external attacks. However, since the firewall based on the attacker database, the unknown may not be detected. In order to address the obstacle, a detection tool could be used. In this research, IDS as an intrusion detection tool was integrated with a firewall to be implemented in IPv6 Mobile to stop the DoS attack. The results of some experiments showed that the integration system could block the attack at 0.9 s in Correspondent Node and 1.2 s in Home Agent. The blocked attack can decrease the network throughput up to 27.44% when a Mobile Node in Home Agent, 28,87% when the Mobile Node in a Foreign Network. The final result of the blocked attack is reducing the average CPU utilization up to 30.99%.

The purpose of the work was to study the fault- tolerant pattern of secure access of computer system nodes to external network resources - the pattern of secure access `Connecting node'. The pattern of secure access `Connecting node' includes a group/cluster (or several groups) of routers, a computing node that includes hardware and software for information protection and communication channels that connect it to the end nodes of the computing system and the external network (network resources that are not controlled by the information protection system). The efficiency assessment and comparative analysis of options for designing a pattern of secure access `Connecting node' according to various efficiency criteria were carried out. In this work, an assessment of the individual and comprehensive efficiency index was carried out. It was assumed that the system is recoverable. The effectiveness of using some options of designing a pattern of secure access in terms of the operational availability factor, as well as a group of parameters - the operational availability factor, service delays of information protection system and the grade of information protection.

This Innovate Practice Full Paper describes our experience with teaching cybersecurity topics using guided inquiry collaborative learning. The goal is to not only develop the students' in-depth technical knowledge, but also “soft skills” such as communication, attitude, team work, networking, problem-solving and critical thinking. This paper reports our experience with developing and using the Guided Inquiry Collaborative Learning materials on the topics of firewall and IPsec. Pre- and post-surveys were conducted to access the effectiveness of the developed materials and teaching methods in terms of learning outcome, attitudes, learning experience and motivation. Analysis of the survey data shows that students had increased learning outcome, participation in class, and interest with Guided Inquiry Collaborative Learning.

Linux is used in a large variety of situations, from private homes on personal machines to businesses storing personal data on servers. This operating system is often seen as more secure than Windows or Mac OS X, but this does not mean that there are no security concerns to be had when running it. Attackers can crack simple passwords over a network, vulnerabilities can be exploited if firewalls do not close enough ports, and malware can be downloaded and run on a Linux system. In addition, sensitive information can be accessed through physical or network access if proper permissions are not set on the files or directories containing it. However, most of these attacks can be prevented by keeping a system up to date, maintaining a secure firewall, using an antivirus, making complex passwords, and setting strong file permissions. This paper presents a list of methods for securing a Linux system from both external and internal threats.

The privacy of people on internet is getting reduced day by day. Data records of many prestigious organizations are getting corrupted due to computer malwares. Computer viruses are becoming more advanced. Hackers are able penetrate into a network and able to manipulate data. In this paper, describes the types of malwares like Trojans, boot sector virus, polymorphic virus, etc., and some of the hacking techniques which include DOS attack, DDoS attack, brute forcing, man in the middle attack, social engineering, information gathering tools, spoofing, sniffing. Counter measures for cyber attacks include VPN, proxy, tor (browser), firewall, antivirus etc., to understand the need of cyber security.

ASA systems (firewall, IDS, IPS) are probable to become communication bottlenecks in networks with growing network bandwidths. To alleviate this issue, we suggest to use Application-aware mechanism based on Deep Packet Inspection (DPI) to bypass chosen traffic around firewalls. The services of Internet video sharing gained importance and expanded their share of the multimedia market. The Internet video should meet strict service quality (QoS) criteria to make the broadcasting of broadcast television a viable and comparable level of quality. However, since the Internet video relies on packet communication, it is subject to delays, transmission failures, loss of data and bandwidth restrictions that may have a catastrophic effect on the quality of multimedia.

The application of the concept of software-defined networks (SDN) has, on the one hand, led to the simplification and reduction of switches price, and on the other hand, has created a significant number of problems related to the security of the SDN network. In several studies was noted that these problems are related to the lack of flexibility and programmability of the data plane, which is likely first to suffer potential denial-of-service (DoS) attacks. One possible way to overcome this problem is to increase the flexibility of the data plane by increasing the depth of programmability of the packet-switching nodes below the level of flow table management. Therefore, this paper investigates the opportunity of using the architecture of deeply programmable packet-switching nodes (DPPSN) in the implementation of a firewall. Then, an architectural model of the firewall based on a hybrid FPGA/CPU data plane architecture has been proposed and implemented. Realized firewall supports three models of DoS attacks mitigation: DoS traffic filtering on the output interface, DoS traffic filtering on the input interface, and DoS attack redirection to the honeypot. Experimental evaluation of the implemented firewall has shown that DoS traffic filtering at the input interface is the best strategy for DoS attack mitigation, which justified the application of the concept of deep network programmability.

In this paper we propose ROS-Defender, a holistic approach to secure robotics systems, which integrates a Security Event Management System (SIEM), an intrusion prevention system (IPS) and a firewall for a robotic system. ROS-Defender combines anomaly detection systems at application (ROS) level and network level, with dynamic policy enforcement points using software defined networking (SDN) to provide protection against a large class of attacks. Although SIEMs, IPS, and firewall have been previously used to secure computer networks, ROSDefender is applying them for the specific use case of robotic systems, where security is in many cases an afterthought.

The goal of this document is to provide knowledge of Security for Industrial Control Systems (ICS,) such as supervisory control and data acquisition (SCADA) which is implemented in power transmission network, power stations, power distribution grids and other big infrastructures that affect large number of persons and security of nations. A distinction between IT and ICS security is given to make a difference between the two disciplines. In order to avoid intrusion and destruction of industrials plants, some recommendations are given to preserve their security.

Protection from DDoS-attacks is one of the most urgent problems in the world of network technologies. And while protect systems has algorithms for detection and preventing DDoS attacks, there are still some unresolved problems. This article is devoted to the DDoS-attack called Pulse Wave. Providing a brief introduction to the world of network technologies and DDoS-attacks, in particular, aims at the algorithm for protecting against DDoS-attack Pulse Wave. The main goal of this article is the implementation of traffic classifier that adds rules for infected computers to put them into a separate queue with limited bandwidth. This approach reduces their load on the service and, thus, firewall neutralises the attack.

As the technology reliance increases, computer networks are getting bigger and larger and so are threats and attacks. Therefore Network security becomes a major concern during this last decade. Network Security requires a combination of hardware devices and software applications. Namely, Firewalls and IPsec gateways are two technologies that provide network security protection and repose on security policies which are maintained to ensure traffic control and network safety. Nevertheless, security policy misconfigurations and inconsistency between the policy's rules produce errors and conflicts, which are often very hard to detect and consequently cause security holes and compromise the entire system functionality. In This paper, we review the related approaches which have been proposed for security policy management along with surveying the literature for conflicts detection and resolution techniques. This work highlights the advantages and limitations of the proposed solutions for security policy verification in IPsec and Firewalls and gives an overall comparison and classification of the existing approaches.

The evolution of the enterprise computing landscape towards emerging trends such as fog/edge computing and the Industrial Internet of Things (IIoT) are leading to a change of approach to securing computer networks to deal with challenges such as mobility, virtualized infrastructures, dynamic and heterogeneous user contexts and transaction-based interactions. The uncertainty introduced by such dynamicity introduces greater uncertainty into the access control process and motivates the need for risk-based access control decision making. Thus, the traditional perimeter-based security paradigm is increasingly being abandoned in favour of a so called "zero trust networking" (ZTN). In ZTN networks are partitioned into zones with different levels of trust required to access the zone resources depending on the assets protected by the zone. All accesses to sensitive information is subject to rigorous access control based on user and device profile and context. In this paper we outline a policy enforcement framework to address many of open challenges for risk-based access control for ZTN. We specify the design of required policy languages including a generic firewall policy language to express firewall rules. We design a mechanism to map these rules to specific firewall syntax and to install the rules on the firewall. We show the viability of our design with a small proof-of-concept.

Distributed Denial of Service (DDoS) attacks remain one of the top threats to enterprise networks and ISPs nowadays. It can cause tremendous damage by bringing down online websites or services. Existing DDoS defense solutions either brings high cost such as upgrading existing firewall or IPS, or bring excessive traffic delay by using third-party cloud-based DDoS filtering services. In this work, we propose a DDoS defense framework that utilizes Network Function Virtualization (NFV) architecture to provide low cost and highly flexible solutions for enterprises. In particular, the system uses virtual network agents to perform attack traffic filtering before they are forwarded to the target server. Agents are created on demand to verify the authenticity of the source of packets, and drop spoofed packets in order protect the target server. Furthermore, we design a scalable and flexible dispatcher to forward packets to corresponding agents for processing. A bucket-based forwarding mechanism is used to improve the scalability of the dispatcher through batching forwarding. The dispatcher can also adapt to agent addition and removal. Our simulation results demonstrate that the dispatcher can effectively serve a large volume of traffic with low dropping rate. The system can successfully mitigate SYN flood attack by introducing minimal performance degradation to legitimate traffic.

To solve the problems associated with large data volume real-time processing, heterogeneous systems using various computing devices are increasingly used. The characteristic of solving this class of problems is related to the fact that there are two directions for improving methods of real-time data analysis: the first is the development of algorithms and approaches to analysis, and the second is the development of hardware and software. This article reviews the main approaches to the architecture of a hardware-software solution for traffic capture and deep packet inspection (DPI) in data transmission networks with a bandwidth of 80 Gbit/s and higher. At the moment there are software and hardware tools that allow designing the architecture of capture system and deep packet inspection: 1) Using only the central processing unit (CPU); 2) Using only the graphics processing unit (GPU); 3) Using the central processing unit and graphics processing unit simultaneously (CPU + GPU). In this paper, we consider these key approaches. Also attention is paid to both hardware and software requirements for the architecture of solutions. Pain points and remedies are described.

Due to the increasing threat of network attacks, Firewall has become crucial elements in network security, and have been widely deployed in most businesses and institutions for securing private networks. The function of a firewall is to examine each packet that passes through it and decide whether to letting them pass or halting them based on preconfigured rules and policies, so firewall now is the first defense line against cyber attacks. However most of people doesn't know how firewall works, and the most users of windows operating system doesn't know how to use the windows embedded firewall. This paper explains how firewall works, firewalls types, and all you need to know about firewall policies, then presents a novel application (QudsWall) developed by authors that manages windows embedded firewall and make it easy to use.

The Distributed Denial of Service (DDoS) attack is a main concern in network security. Since the attackers have developed different techniques and methods, preventing DDoS attacks has become more difficult. Traditional firewall is ineffective in preventing DDoS attacks. In this paper, we propose a new type of firewall named XFirewall to defend against DDoS attacks. XFirewall is a temporary firewall and is created when an attack occurs. Also, XFirewall will be configured with dynamic rules based on real-time traffic analysis. We will discuss in detail the design and algorithm for generating an XFirewall.

We measure the prevalence and uses of TLS proxies using a Flash tool deployed with a Google AdWords campaign. We generate 2.9 million certificate tests and find that 1 in 250 TLS connections are TLS-proxied. The majority of these proxies appear to be benevolent, however we identify over 1,000 cases where three malware products are using this technology nefariously. We also find numerous instances of negligent, duplicitous, and suspicious behavior, some of which degrade security for users without their knowledge. Distinguishing these types of practices is challenging in practice, indicating a need for transparency and user awareness.

A key use of software-defined networking is to enable scale-out of network data plane elements. Naively scaling networking elements, however, can cause incorrect security responses. For example, we show that an IDS system which operates correctly as a single network element can erroneously and permanently block hosts when it is replicated. Similarly, a scaled-out firewall can incorrectly block hosts.

In this paper, we provide a system, COCONUT, for seamless scale-out of network forwarding elements; that is, an SDN application programmer can program to what functionally appears to be a single forwarding element, but which may be replicated behind the scenes. To do this, we identify the key property for seamless scale out, weak causality, and guarantee it through a practical and scalable implementation of vector clocks in the data plane. We formally prove that COCONUT enables seamless scale out of networking elements, i.e., the user-perceived behavior of any COCONUT element implemented with a distributed set of concurrent replicas is provably indistinguishable from its singleton implementation. Finally, we build a prototype of COCONUT and experimentally demonstrate its correct behavior. We also show that its abstraction enables a more efficient implementation of seamless scale-out compared to a naive baseline.

This work was funded by the SoS lablet at the University of Illinois at Urbana-Champaign.

OpenFlow, as the prevailing technique for Software-Defined Networks (SDNs), introduces significant programmability, granularity, and flexibility for many network applications to effectively manage and process network flows. However, because OpenFlow attempts to keep the SDN data plane simple and efficient, it focuses solely on L2/L3 network transport and consequently lacks the fundamental ability of stateful forwarding for the data plane. Also, OpenFlow provides a very limited access to connection-level information in the SDN controller. In particular, for any network access management applications on SDNs that require comprehensive network state information, these inherent limitations of OpenFlow pose significant challenges in supporting network services. To address these challenges, we propose an innovative connection tracking framework called STATEMON that introduces a global state-awareness to provide better access control in SDNs. STATEMON is based on a lightweight extension of OpenFlow for programming the stateful SDN data plane, while keeping the underlying network devices as simple as possible. To demonstrate the practicality and feasibility of STATEMON, we implement and evaluate a stateful network firewall and port knocking applications for SDNs, using the APIs provided by STATEMON. Our evaluations show that STATEMON introduces minimal message exchanges for monitoring active connections in SDNs with manageable overhead (3.27% throughput degradation).

Security in Mobile Ad Hoc networks is still ongoing research in the scientific community and it is difficult bring an overall security solution. In this paper we assess feasibility of distributed firewall solutions in the Mobile Ad Hoc Networks. Attention is also focused on different security solutions in the Ad Hoc networks. We propose a security architecture which secures network on the several layers and is the most secured solution out of analyzed materials. For this purpose we use distributed public key infrastructure, distributed firewall and intrusion detection system. Our architecture is using both symmetric and asymmetric cryptography and in this paper we present performance measurements and the security analysis of our solution.

Detecting attacks that are based on unknown security vulnerabilities is a challenging problem. The timely detection of attacks based on hitherto unknown vulnerabilities is crucial for protecting other users and systems from being affected as well. To know the attributes of a novel attack's target system can support automated reconfiguration of firewalls and sending alerts to administrators of other vulnerable targets. We suggest a novel approach of post-incident intrusion detection by utilizing information gathered from real-time social media streams. To accomplish this we take advantage of social media users posting about incidents that affect their user accounts of attacked target systems or their observations about misbehaving online services. Combining knowledge of the attacked systems and reported incidents, we should be able to recognize patterns that define the attributes of vulnerable systems. By matching detected attribute sets with those attributes of well-known attacks, we furthermore should be able to link attacks to already existing entries in the Common Vulnerabilities and Exposures database. If a link to an existing entry is not found, we can assume to have detected an exploitation of an unknown vulnerability, i.e., a zero day exploit or the result of an advanced persistent threat. This finding could also be used to direct efforts of examining vulnerabilities of attacked systems and therefore lead to faster patch deployment.

Eduroam is a secure WLAN roaming service between academic and research institutions around the globe. It allows users from participating institutions secure Internet access at any other participating visited institution using their home credentials. The authentication credentials are verified by the home institution, while authorization is done by the visited institution. The user receives an IP address in the range of the visited institution, and accesses the Internet through the firewall and proxy servers of the visited institution. However, access granted to services that authorize via an IP address of the visited institution may include access to services that are not allowed at the home institution, due to legal agreements. This paper looks at typical legal agreements with service providers and explores the risks and countermeasures that need to be considered when using eduroam.